SMITHSONIAN CONTRIBUTIONS TO BOTANY NUMBER 68 

Morphological, Anatomical, 

and Taxonomic Studies in 

Anomochloa and Streptochaeta 

(Poaceae: Bambusoideae) 

Emmet J. Judziewicz and Thomas R. Soderstrom 

SMITHSONIAN INSTITUTION PRESS 

Washington, D.C. 

1989 
ABSTRACT 

Judziewicz, Emmet J., and Thomas R. Soderstrom. Morphological, Anatomical, and 

Taxonomic Studies in Anomochloa and Streptochaeta (Poaceae: Bambusoideae). Smithsonian 

Contributions to Botany, number 68,52 pages, 24 figures, 1 table, 1989.-Although resembling 

the core group of the bambusoid grasses in many features of leaf anatomy, the Neotropical 

rainforest grass genera Anomochloa and Streptochaeta share characters that are unusual in the 

subfamily: lack of ligules, exceptionally long microhairs with an unusual morphology, a 

distinctive leaf blade midrib structure, and 5-nerved coleoptiles. Both genera also possess 

inflorescences that are difficult to interpret in conventional agrostological terms. Anomochloa 

is monotypic, and A. marantoidea, described in 1851 by Adolphe Brongniart from cultivated 

material of uncertain provenance, was rediscovered in 1976 in the wet forests of coastal Bahia, 

Brazil. The inflorescence terminates in a spikelet and bears along its rachis several scorpioid 

cyme-like partial inflorescences. Each axis of a partial inflorescence is subtended by a keeled 

bract and bears as its first appendages two tiny, unvascularized bracteoles attached at slightly 

different levels. The spikelets are composed of an axis that bears two bracts and terminates in 

a flower. The lower, chlorophyllous, deciduous spikelet bract is separated from the coriaceous, 

persistent, corniculate upper bract by a cylindrical, indurate internode. The flower consists of 

a low membrane surmounted by a dense ring of brown cilia (perigonate annulus) surrounding 

the andrecium of four stamens, and an ovary bearing a single hispid stigma. Other peculiarities 

of A. marantoidea include its hollow leaf sheaths and long, hollow, bipulvinate pseudopetioles 

and chromosome number of n = 18. The caryopsis and embryo are large, but their structure is 

typically bambusoid. Streptochaeta consists of three species and one subspecies (S. spicata 

subsp. ecuatoriana, newly described here) and conforms to the bambusoid core group in 

seedling morphology and leaf anatomy. Streptochaeta and Anomochloa are quite divergent but 

may be more closely related to each other than to any other grass. They share features that 

indicate affinities with the Olyreae. 

OFFICIAL PUBLICATION DATA is handstamped in a limited number of initial copies and is 

recorded in the Institution’s annual report, Smithsonian Year. SERIES COVER DESIGN: Leaf 

clearing from the katsura tree Cercidiphyllum japonicum Siebold & Zuccarini. 

Library of Congress Cataloging-in-Publication Data 

Judziewicz, Emmet J. 

Morphological, anatomical, and taxonomic studies in Anomochloa and Streptochaeta (Poaceae, Bambusoideae). 

(Smihsonian contributions to botany ; no. 68) 

Bibliography: p. 

Supt of Docs. no. SI 1.29:68 

1. Anornochloa 2. Streptochaeta I. Soderstrorn, Thomas R. 11. Title. 111. Series. 

QKlS2747 no. 68 581 s [584’.9] 88-600187 [QK495.G74] 
Contents 

Page 

Introduction ........................................ 1 

Materials and Methods ................................. 1 

Acknowledgments ................................... 2 

Anomochloa Brongniart .................................. 2 

History and Rediscovery. by T.R. Sodcrstrom ..................... 2 

1 . Anomochloa marantoidea Brongniart ...................... 5 

Morphology-Anatomy ................................. 12 

Culm and Leaf Sheath ............................... 12 

Ligule and Pseudopetiole .............................. 12 

Pulvini ........................................ 12 

Leaf-blade Anatomy ................................ 13 

Inflorescence .................................... 15 

Spikelet ....................................... 18 

Fruit ......................................... 22 

Chromosomes ..................................... 22 

Discussion ....................................... 22 

Habit ........................................ 22 

Leaves ........................................ 22 

Inflorescence .................................... 25 

Spikelet ....................................... 25 

Fruit ......................................... 28 

Reproductive Biology ................................ 28 

Streptochaeta Schradcr ex Nees von Esenbcck ..................... 29 

History ......................................... 29 

Key to the Species of Streptochaeta ........................ 29 

1 . Streptochaeta sodiroana Hackel ........................ 30 

2a . Streptochaeta spicata subsp . spicata Schrader ex Nees von Esenbeck .... 34 

2b . Streptochaeta spicata subsp . ecuatoriana. new subspecies .......... 39 

3 . Streptochaeta angustijolia Soderstrom ..................... 39 

Morphology-Anatomy ................................. 41 

Culm. Leaf Sheath. and Pulvinus .......................... 41 

Leaf-blade Anatomy ................................ 41 

Inflorescence and Pseudospikelets ......................... 42 

Fruit ......................................... 43 

Chromosomes ..................................... 43 

Habit ........................................ 44 

Leaves ........................................ 44 

Inflorescence and Pseudospikelets ......................... 44 

Reproductive Biology ................................ 46 

Interspecific Relationships ............................. 46 

Phylogenetic Position of Anomochloa and Streptochaeta ................ 46 

Index ........................................... 52 

Taxonomy ........................................ 5 

Taxonomy ....................................... 29 

Discussion ...................................... -44 

Fruit ......................................... 45 

Literature Cited ...................................... 49 

111 

Morphological, Anatomical, 

and Taxonomic Studies in 

Anomochloa and Streptochaeta 

(Poace ae : B ambus oideae) 

Emmet J. Judziewicz and Thomas R. Soderstrom 

Introduction 

The eight tribes of herbaceous bamboos have long interested 

the agrostologist concerned with tracing the evolution of the 

Poaceae. Although they appear to have their closest affinities 

with the woody bamboos (Bambuseae) of the Bambusoideae, 

the intertribal relationships of the herbaceous group have 

remained uncertain until recently because of a lack of suitable 

material for the study of such taxonomically critical characters 

as inflorescence, spikelet, lodicule, gynecium, fruit, and 

seedling morphology. Of the eight tribes the Olyreae, with 

about 20 genera and over 100 species, is native only to the 

New World and is dealt with in detail in the papers of 

Soderstrom and collaborators (Calder6n and Soderstrom, 1973, 

1980). In leaf anatomy this tribe appears to be closest to the 

woody bamboos (Bambuseae) (Soderstrom and Ellis, 1987). 

It may also be related to the poorly known Buergersiochloeae, 

a monotypic tribe of northern New Guinea (Fijten, 1975). The 

other tribes of herbaceous bamboos are more isolated. For 

example, the Phareae, with inverted, obliquely veined leaves 

bearing distinctive fibrous epidermal bands, but lacking 

bicellular microhairs, is perhaps the most isolated tribe among 

the herbaceous bamboos. The Streptogyneae, with a unique 

seedling morphology for the subfamily (Soderstrom, 1981a), 

is nearly as isolated as the Phareae (Soderstrom et al., 1987). 

While the African Puelia (Puelieae) and Guaduella (Guaduelleae) bear many-flowered spikelets of a typical graminoid 

type, more material, including caryopses and seedlings, is 

required to understand their affinities. 

Emmet J. Judziewicz, Department of Botany, University of Wisconsin, 

Madison, Wisconsin 53706. Thomas R. Soderstrom (deceased}, 

Department of Botany, National Museum of Natural History, 

Smithsonian Institution, Washington, D.C. 20560. 

The two remaining tribes, the monotypic Anomochloeae and 

Streptochaeteae, are the subject of this paper. Above all others 

these Neotropical forest herbs have intrigued agrostologists 

because their inflorescence and spikelet structures are so 

different from those of other grasses. They have been called 

the most primitive grasses, and until recently some workers 

have questioned whether they were truly graminaceous 

(Campbell, 1985). 

The present investigation was made possible because of the 

rediscovery of Anomochloa. Material gathered in 1976, 1978, 

1982, 1983, and 1986 by various botanists is the basis of our 

studies of the inflorescence and spikelet structure and 

taxonomic affinities of Anomochloa marantoidea. T.R. Sodermom wrote the section herein on the history and rediscovery 

of this taxon. 

For purposes of comparison we have also studied Streptochaeta. Inflorescences of both genera are unique within the 

grass family and the present study is intended to clarify the 

relationship of these peculiar bamboos. 

MATERIALS AND METHODS 

Herbarium specimens of Anomochloa and Streptochaeta 

were examined from the following herbaria (acronyms follow 

Holmgren et al., 1981): AAU, B, BM, BR, CANB, CAY, 

CEPEC, DUKE, F, G, IBGE, INPA, ISC, K, L, LE, M, MO, 

NA, NY, P, PDA, QCA, R, RB, S, SI, UC, US, W, and WIS. 

Observations of living plants of Streptochaeta were made by 

Soderstrom (Costa Rica, 1966; Brazil, 1972) and Judziewicz 

(Costa Rica, Panama, 1983), and of Anomochloa by Soderstrom (October 1983) and Judziewicz (February and March 

1986). Some of these plants were preserved in FAA (90% 

ethanol, 5% acetic acid, 5% formalin) and later transferred to 

1 
2 SMITHSONIAN COSTRIBUTIONS TO BOTASY 

70% ethanol (see Appendix). 

The culms, leaves, and reproductive structures of voucher 

specimens were studied using a Wild M5 dissecting microscope. These structures were also studied by serial crosssections at thicknesses of 8-13 pm using a rotary microtome. 

Before dehydration with dimethoxypropanol (DMP), infiltration with tertiary butyl alcohol (TBA), and embedding in 

paraffin, leaves and spikelets were soaked for several days in 

hydrofluoric acid (HF) in order to remove silica. For the study 

of bicellular microhairs in Anomochloa marantoidea a 

preserved leaf was stained in Chlorazol Black E and areas with 

abundant microhairs were scraped with a razor blade. Formal 

descriptions of the leaf anatomy of Anomochloa and Streptochaeta follow the model of Soderstrom et al. (1987). Embryos 

of both genera were dissected out of the caryopses, rehydrated 

using Aerosol-OT, embedded in agar, then dehydrated and 

embedded in paraffin using the procedure described above. 

Sections were cut at widths of from 4-10 pm, and stained with 

Chlorazol Black E. Starch grains from caryopses were 

sectioned with a freezing microtome and then stained with 1,KI. 

Epidermal scrapes were prepared using the method of 

Tomlinson (1961). Photomicrographs were made using Zeiss 

microscopes with green filters and Kodak Panatomic X ASA 

32 film. 

ACLYO WLEDGM ESTS 

We are grateful to Alice R. Tangerini and Gesina B. 

Threlkeld for preparing the illustrations, and to Stanley 

Yankowski for the anatomical preparations, all of the 

Smithsonian Institution (SI). Many people helped us in our 

field work and we are especially grateful to Dr. Luis A. M. da 

Silva (Centro de Pesquisas do Cacao, or CEPEC), Dmitri 

Sucre, Talmon S. dos Santos, and Gustavo Martinelli. We 

would like to thank especially Dr. Paulo de T. Alvim, director 

of the Cacao Research Center, CEPEC, in Itabuna, Bahia, 

Brazil, who on several occasions extended to C.E. CaldeOh 

and us the use of the facilities of the institute. In Paris the 

assistance given by Dra. Alicia Lourteig and M. Jolinon in 

locating Brongniart’s manuscripts and archival correspondence 

is acknowledged. In London the facilities of the Royal 

Horticultural Library, Vincent Square, were generously extended, Dr. Leslie Garay of the orchid herbarium, Harvard 

University, offered helpful information. We also appreciate the 

advice and comments of Dr. Roger Ellis (Botanical Institute, 

Pretoria) and Dr. H. Trevor Clifford (University of Queensland) 

on certain aspects of the study. Victor E. Krantz (SI) produced 

the photographs for Figures 8 and part of 9. Judziewicz 

conducted part of the research that led to this paper while a 

predoctoral fellow at the Smithsonian Institution (September 

1985-August 1986). His field work in Brazil was funded by 

the Smithsonian’s Neotropical Lowland Ecosystems Program 

and the E.K. and O.N. Allen Herbarium Fund of the 

Department of Botany, University of Wisconsin, Madison. 

We also thank the curators of the herbaria from which we 

borrowed specimens. 

Anomochloa Brongniart 

Anornochluu Brongniart, 1850:57 [nomen nudum]; 1851 :368. 

HISTORY ASD REDISCOVERY 

by T.R. Soderstrom 

When Adolphe Brongniart described Anomochloa (1850, 

1851) he chose an apt name for this weird and remarkable, truly 

anomalous grass that reportedly had come from Brazil. One 

or more plants of the genus were in cultivation in the 

greenhouse of the Jardin dcs Plantes in Paris in the 1840s. 

When Brongniart, then director of the MusEum d’Histoire 

Naturelle, saw the plant he decided it was a grass and described 

it as Anomochloa marantoidea, because the clustered broad 

pseudopetiolate leaves gave it the appearance of a genus of 

Marantaceae. 

A plant was later sent to Kew by Charles Decaisne, Professor 

of Culture at the Serres (greenhouses) du Jardin des Plantes 

and was cultivated there until at least 1866. Herbarium 

specimens made of the plants at Paris and Kew represented the 

only material available for study by later workers. The desire 

to rediscover this genus and have fresh material for further 

study was well expressed by Agnes Arbcr who made studies 

on herbarium material (1934:131-133): 

It will be recognised even from this brief description, that Anomochloa, if a 

member of the Gramineae, is a most erratic one. Its rediscovery is much to be 

desired; a complete study of its structure and development would be of deepest 

interest. 

Besides Arber, several other botanists studied the plant from 

dried specimens. Schuster (19O9:3&32) examined the spikelet 

of Anomochloa as part of his dissertation on the morphology 

of grass flowers. Page (1947) noted the presence of large 

mesophyll cells in the leaf, based on an external study of the 

single leaf in the collections at the U.S. National Herbarium. 

Metcalfe (1960:28-29) was the first to give a description of the 

leaf cross-section anatomy and epidermis, stating that “this 

grass has obvious points in common with the bamboos.” 

My own early studies of herbaceous bamboos began during 

field work in Guyana in 1962 and Suriname in 1963 when I 

collected several genera of bambusoid grasses. This work led 

me to the literature on Anomochloa and a desire to relocate 

this grass in particular. Its rediscovery took many paths and I 

think the story interesting enough to relate here. 

Brongniart (1851), in his beautiful paper on the new genus, 

did not mention anything about the plant in cultivation and 

gave as its provenance only the name of Morel and the province 

of Bahia, Brazil. The earliest mounted specimen at Paris has 

two labels, one a handwritten note signed “herb. Houllet, July 

1890,” stating: “This plant was given by Monsieur Morel who 
NUMBER 68 3 

received it from Brazil from Monsieur Pinelle from Morro 

chemado, Province of Rio de Janeiro in 1842” [my translation 

from the French]. The other label, with a printed heading of 

the Paris Herbarium, has the following information [my 

translation]: “Brazil. Bahia. Monsieur Porte, given by Monsieur Morel. Paris Botanical Garden, August 1848.” The U.S. 

National Herbarium has two herbarium collections, one with 

a piece of inflorescence from a sheet at Paris, the other with a 

floret from a sheet at Leiden (in turn from the Balansa 

Herbarium at Paris), in addition to a leaf from a cultivated 

specimen at Kew. 

Both of the US sheets have annotations by Agnes Chase 

who wrote “Bahia $- Porto,” having misread “Bahia E[onsieur] Porto.” She added a note, “Is ‘Bahia’ alleged locality for 

this ‘bay,’ meaning bay of Rio de Janeiro?” This was a logical 

conclusion since the word for bay in Portuguese is “bahia.” 

Mrs. Chase, who collected for several months in Brazil in 1924 

and 1925, was anxious to relocate this grass and thought that 

it grew around Rio de Janeiro where she spent several days. 

In the files of L.B. Smith (Smithsonian Institution) is a letter 

of 6 December 1927 to Dr. Smith (who was going to Brazil 

the following year) from Mrs. Chase, who wrote the following. 

The grass I most wanted in Brazil and failed to find was Anomochloa. It 

occurs to me that you may like to read the original manuscript of the paper I 

had to reduce to 50 percent for the Smithsonian Report, so I shall send it. 

Please return it when you have read it. In this manuscript you will see that this 

grass was described from “the province of Bahia.” In the Paris Museum last 

May I found a note on the specimen in that herbarium which shows that “bahia” 

(bay in Portuguese) referred to the bahia of Rio de Janeiro . . .. I can not find 

where Mom Chemado (if Chemado is a proper name) is . . . Anomochloa is a 

broad-leaved grass obviously of shaded places. So Prov. Rio de Janeiro is a 

far more likely place for it than and or semiarid Bahia. 

The many steps that led to the eventual rediscovery of 

Anomochloa actually started with my first trip to Brazil in 

1964 when I accompanied Dr. Howard S. Irwin, Jr., on his 

expedition to the cerrados of the central part of the country. 

In BrasIlia I made the acquaintance of a young botanist, Romeu 

BelEm, who collected with us one day in a gallery forest near 

the city. There we found large clumps of a species of the 

herbaceous bamboo, Olyra, with beautifully purple-mottled 

culms (later described as 0. taquara Swallen). I showed BelEm 

how to make a collection of such a grass and encouraged him 

to look for these on his collecting trips. He was shortly to go 

to Bahia, where he was being sent by Dr. Joao Murca Pires, 

to start an herbarium at the CEPEC in Itabuna. 

The first collections in that now-rich herbarium are those 

of BelEm. His collections and those of others that followed are 

cited in a paper by Scott Mori and L.A. Silva (1979), the 

former of whom spent two years (1978-1980) collecting in the 

wet coastal forest region of Bahia and curating the CEPEC 

herbarium. Shortly after BelEm’s arrival in Itabuna we received 

a small package of bambusoid grasses, many unknown to me 

at the time and quite different from the others that I had so far 

studied. Among these was a collection that BelEm made with 

C.M. MagalhAes (no. 886) in 1965. I had provisionally dubbed 

that collection “Raddiolyra” when I first saw it because it 

resembled both Raddia and Olyra but was certainly distinct 

from either of them. I later described this as a new genus, 

Sucrea (Soderstrom, 1981b). 

In June 1967 in a forest near Maracay, Venezuela, I noticed 

that insects were always to be found around the inflorescences 

of the bambusoid genus, Parianu. Since this association 

seemed to be common I made collections of the plants and the 

insects, which in this case turned out to be a new genus of 

Diptera (Cecidomyiidae), described by GagnE (1969). The 

possibility of insect pollination in these herbaceous bambusoid 

grasses that grew in the rainforest was intriguing and deserved 

further investigation. Upon my return from Venezuela I 

discussed my observations with an Argentine colleague, CleofE 

CalderOn, who was working in my laboratory at the time. We 

decided to pursue the problem and made plans for her to visit 

a number of localities in Central and South America where she 

would collect bambusoid grasses and make observations on 

the insects that visited the inflorescences. Thus in late 1967 

Calderon left for Panama and continued on eColombiaLand

Brazil, making collections in each of these localities. Most of 

the insect observations were made in the forests around Belem, 

Para Brazil, and the results of this work were published in 

Soderstrom and Calderon (1971). 

However, the most interesting part of the trip, from the 

standpoint of new bamboo taxa, turned out to be Bahia, which 

was included in her itinerary because of the interesting 

collections that Romeu Belem had sent us. Calderon’s further 

collections from Bahia showed the region’s wet forest region, 

where Itabuna was located, to be rich indeed in bambusoid taxa. 

Up to this point we still had no idea where Anomochloa 

might be found. However, based on Brongniart’s statement 

(1851) and the other kinds of bambusoid grasses found by 

BelCm and Calder6n in Bahia, that locality was a good 

possibility. Mrs. Chase, who had discounted Bahia as a suitable 

habitat, felt it was too arid but she was referring to the part of 

the state where she had traveled, between Salvador and 

Juazeiro on the Rio Sao Francisco. She was not familiar with 

the narrow strip of tropical rainforest along the coast. 

With funds from the National Geographic Society and 

Smithsonian Institution, Caldeoh and I traveled to Brazil in 

1972 to explore various parts of the eastern coastal forest with 

the purpose of finding Anomochloa, along with another 

bambusoid grass, Diandrolyra, known only from cultivation 

at Kew. At that time we felt that Anomochloa could be found 

either in Bahia or in the mountains around Rio de Janeiro. 

Thus Calderon returned for further exploration in Bahia, where 

she collected with R.S. Pinheiro and Talmon S. dos Santos. I 

returned to the states of Rio de Janeiro and Espirito Santo, 

collecting with Dimitri Sucre of the Jardim Botanic0 in Rio 

de Janeiro. These concurrent trips yielded a fine collection of 

bamboos, including two species of Diandrolyra, new genera, 

and many new species. But Anomochloa still eluded us. 

It was time now to see if information about those persons 

involved with the original collection might offer a clue as to 
4 SMITHSONIAN COSTRIBUTIONS TO BOTASY 

where the plant was first collected. Who were Morel, Pinel, 

and Porte-names associated with Brongniart in the beginning? One of the original labels stated “Bahia M. Porte” and 

“Dn par [given by] M. Morel.” Since I had seen these names 

in species of orchids, a search through the horticultural 

literature of the time was undertaken by an assistant, Stephen 

Cahir (SI), during the summer of 1973. Some leads came about 

through this effort and that fall I spent a few weeks in London 

and Paris continuing the search. This involved literature 

reviews at the Royal Horticultural Society library in London, 

the archives at Kew herbarium, of old manuscripts at the Paris 

herbarium, and a visit to the records in the town archives of 

St. Mande where Morel had lived. Through all of this effort 

we were persuaded to return to Bahia, which we were now 

convinced was the home of Anomochloa. 

Charles Morel had lived in a suburb of Paris called St. 

Mande, which is now a part of the city itself. The town records 

show that he was born in Reims (Maxne) on 28 July 1793 and 

was listed as a proprietaire (property owner?). The horticultural 

literature speaks highly of this gentleman and his greenhouses 

with their large collection of rare orchids. Morel was active in 

horticultural societies and had several correspondents who 

sent him orchids from abroad. One of these correspondents 

was Monsieur Pinel, who sent material from Brazil. Morel 

must have received material of Anomochloa, which he gave 

to Brongniart for cultivation in the greenhouses of the Museum. 

Morel was the author of a book on orchid culture (1855), 

which he dedicated to his friend, Prof. Brongniart. On page 9 

he speaks of Pinel from Rio and Porte of Bahia: “This is the 

place to pay just tribute and give thanks to M. Pinel of Rio de 

Janeiro and to M. Porte of Bahia, for it is to their activity and 

their good taste that we owe the greater part of beautiful plants 

of these regions” [my translation from the French]. 

Monsieur (or Chevalier) Pinel, a merchant who resided in 

Bahia, appears in the literature with two spellings, Pinel and 

Pinelle. Pinel, whose first name I have not found, collected 

living plants, probably from the region of Rio de Janeiro and 

sent them to horticultural establishments in France and 

Belgium. Mulford Foster purportedly remarked that the 

bromeliad, Aechmea pineliana, was named possibly for Dr. 

Pinel, French consul in Rio de Janeiro at the time (1851), but 

I have not been able to confirm this. There are many plants 

named for Pinel and records of his sending material to Morel 

in Paris. The name of “Morro chemado” appears more than 

once in Pinel collections, one of which is for an orchid with 

locality “Station Sommite des Serra de Morro-queimado.” I 

collected on a Morro Queimado in Rio de Janeiro, which was 

within the boundaries of the Tijuca forest, but I do not know 

if this is the same locality. It is possible that Pinel lived in the 

area during the last century and that “M. Pinel, Morro 

chemado” referred to the man and where he lived rather than 

a locality for Anomochloa (which he may not have collected). 

On the label of the type of the bromeliad, Aechmea 

(Echinostachys) pineliana Brongniart in the Houllet herbarium, 

which is part of the Paris herbarium, is a note: “This plant has 

been sent to Mr. Morel by Mr. Pinel of Morro-chemado (near 

Rio de Janeiro) in 1846 and has been introduced into botanical 

culture by him [Morel?]” [translation from the French by E. 

Judziewicz]. This again suggests that the plant was sent by 

Pinel of Morro-chemado. 

Marius Porte, whose name appears on one of the Paris labels 

as having sent a plant to Pinel, was a businessman in Bahia. 

Like Pinel he must have been interested in exotic plants for 

horticulture such as orchids. Only because of its great beauty 

and possibility for horticulture would Pinel have collected a 

grass such as Anomochloa and he most likely would have 

mistaken it for a member of the Marantaceae. I was hoping 

that Porte, in his correspondence in the Paris Museum archives, 

would have described some of his collecting localities. But I 

found only three letters, all from Manila to Prof. Brongniart 

in 1860, and remarking on the orchids of the Philippines where 

he had moved. Porte is said to have died shortly after arrival 

due to the results of a long and tedious journey to the 

Philippines from Brazil. 

Adolphe Brongniart was Professor of Botany at the Paris 

Museum and at one time its director. He was an expert in 

many fields, including botany and paleobotany. His paper on 

Anomochloa is superb and his analysis and illustration of the 

original plant outstanding. At the Paris Herbarium, M. Jolinon 

led me to boxes of old manuscripts where I came upon the 

original handwritten manuscript of Brongniart on Anomochloa. 

He included sketches of his dissections (which were not 

published) and the spikelet he had studied was still attached 

to the paper in an envelope. 

In 1975 Calderon and I again were granted funds from the 

National Geographic Society to return to Brazil and intensify 

our field efforts in Bahia. We spent January through March in 

the eastern coastal forests of the state, headquartered at CEPEC 

in Itabuna. We each made several separate trips of about two 

weeks each to different areas, and we returned to Itabuna for 

a few days in between each trip to prepare the herbarium 

specimens. 

Our efforts were finally rewarded with the rediscovery of 

Anomochloa on 21 April 1976. Calderon was traveling along 

a small road with Sr. Talmon S. dos Santos near the city of 

Una, Bahia. Cleo felt a peculiar-or psychic, as she put 

it-urge to stop near a particular wooded area. Not far into the 

woods, which bordered a cultivated area of cacao on somewhat 

rocky slopes, they came upon a colony of the grass. Further 

observations of the colony were made by Victoria Hollowell 

(University of South Carolina) in 1982 and by myself in 1983. 

In 1986, another colony was found by dos Santos and 

Judziewicz who had gone to Brazil to make field observations 

for the present study. 

The rich forested areas in the Bahian municipality of Una, 

where Anomochloa is native, are rapidly disappearing, a 

common story today in the Neotropics. The only populations 

of Anomochloa with which we are familiar occur on rocky 

slopes adjacent to cacao plantations; these may survive as long 

as the plantations are not expanded. Any opening in the canopy 
NUMBER 68 5 

with a concommitant increase in light intensity, however, could 

well cause these communities to succumb. A few plants are in 

cultivation at Rio de Janeiro and in the United States but they 

are not thriving and, like the plants of 19th century Paris 

greenhouses, they have never attained the robust size observed 

in the tall, densely shaded, and rocky rainforest in which they 

are native. Unless there are colonies still to be discovered we 

are probably facing the imminent demise of this unique grass. 

TAXONOMY 

1. Anomochloa marantoidea Brongniart 

FIGURFS 1-4 

Anomochloa maranfoidea Brongniart. 1851:368. pl. 23. [Type: Brazil, Bahia: 

“e provincia Bahiensi Brasiliae accepit clar. Morel, Morro Queimado,” anno 

1842, without collector [or collector Pmel?], cultivated in Pans, August 

1848 (Holotype, P; photograph and fragment, US; isotype, P).] 

A. macrantoidea Brongniart in Pritzel, 1866:74 [error for A. marantoidea 

Brongniart.] 

DESCRIPTION.--PI~~~S cespitose, to 1 m tall in manystemmed loose clumps, prop roots not present; rhizomes 

sympcdial, 0.5-5 cm long, to 7 mm in diameter, papery and 

weak. 

Culms weak, up to 0.5 m tall, all but the uppermost leaves 

borne at the base of the plant; bladeless sheaths below, 

preceding 5-10 fully developed leaves, the lowest with ovate 

leaf blades, several mm long, finely puberulent, these grading 

above into longer linear ones, the Uppermost bladeless sheath 

linear, up to 23 cm long; leaves with reduced, transitional 

blades not present. 

Leaves 4-7 per culm, all clustered at the base of the culm 

except frequently for the uppermost one; the bases of the 

sheaths strongly two-ranked and divergent, the blades held at 

different heights above the ground; leaf sheaths erect, 

yellowish green, hollow, striate, open, 15-30 cm long and up 

to 1 cm wide (folded width), semicircular in cross-section, the 

margins extended into prominent membranous wings up to 5 

mm wide near the base of sheath, these narrowing abruptly to 

a width of 1-2 mm near the apex, with one margin prolonged 

into a rounded, glabrous auricle 1-3 mm long; summit of 

sheath without lateral appendages and oral setae; inner ligule 

a dense, emarginate fringe of clear cilia 1-2 mm long, not 

membranous; outer ligule absent; pseudopetioles strongly 

divergent from summit of sheath, (5)13-18(23) cm long, 

hollow, grooved adaxially, bipulvinate, the lower pulvinus up 

to 3 mm long, the upper pulvinus up to 5 mm long, both pulvini 

solid, turgid, dark-colored, and covered with clear, appressed 

hairs up to 1.5 mm long, especially on the adaxial surface; 

expanded portion of blade (18)2540 cm long, (4)6-10 cm 

wide, narrowly lanceolate to most commonly oblonglanceolate, the margins parallel in the lower half of the blade, 

then gradually tapering to the apex in the upper portion; lamina 

thin, papery, glabrous above, scaberulous below, the venation 

almost strictly parallel, with nearly all of the nerves meeting 

at the base; base truncate to slightly subcordate with the slightly 

auriculate portions on each side of the upper pulvinus slightly 

upturned; midrib raised on both surfaces, prominent and with 

slightly overhanging margins adaxially (0.8-1.2 mm wide near 

the base of the blade), low dome-shaped and not as prominent 

abaxially (where 0.4-0.5 mm wide); blade margins glabrous, 

or scaberulous near apex; primary lateral veins 4-6 on each 

side of the midrib; tertiary lateral veins spaced 0.8-1 mm apart, 

prominent only on the lower (abaxial) surface, transverse 

veinlets present, also prominent only abaxially: a vein 

intermediate in size between the primary and tertiary lateral 

veins often present midway between each pair of primary 

lateral veins: uppermost leaf of culm frequently small, with a 

slightly inflated leaf sheath about 10 cm long, a short 

pseudopetiole, and the expanded portion of the lamina ovate, 

10-15 cm long. 

Inflorescence borne on a subglabrous peduncle 5-7 cm long, 

terminal (but often inconspicuous because of the overtopping 

leaf blades on the same shoot), spike-like, often curved when 

developing but straight at maturity, laterally compressed and 

bilaterally symmetrical, 7-14 cm long, 1.3-2.5 cm wide (or 

up to 5 cm wide when bracts subtending partial inflorescences 

(main branches) fully spread at maturity), terminating in a fully 

developed spikelet; rachis zigzag, puberulent (especially below 

the nodes), alternately bearing 4-7 partial inflorescences, the 

lowest partial inflorescence often separated from the upper 

ones by an exposed portion of the rachis up to 5 cm long; 

general bracts subtending each partial inflorescence 4.5-9 cm 

long, folded width 0.7-1 cm, lanceolate, attenuate, rounded 

on the back but somewhat carinate near apex, prominently 

many-nerved and cross-veined, green, the general bract 

subtending the lowermost partial inflorescence always appressedascending and frequently bearing a small blade up to 5 cm 

long, the general bracts subtending the upper partial inflorescences always strongly overlapping, bladeless, gradually 

smaller and becoming divergent from the rachis with age. 

Partial injlorescences bearing up to 5 spikelets in a secund 

arrangement along a greatly twisted axis: main axis of partial 

inflorescence erect, terminating in a spikelet borne on a 

thickened and slightly obconic pedicel 7-15 mm long and 2-3 

mm wide; main axis bearing near its base on the adaxial side 

2 linear, membranous, nerveless, apically brown-ciliate, and 

unequal bracteoles, the smaller member linear, delicate, not 

keeled, up to 5 mm long, the larger attached slightly higher 

on the branch, typically lanceolate, strongly keeled, up to 10 

mm long; main axis bearing above the bracteole pair on the 

side opposite the rachis a membranous to scarious, elliptic or 

ovate bract 7.5-15 mm long with a strong, often ciliate 

midnerve and several faint lateral nerves, often ciliate at the 

apex; this bract subtending a lateral branch, the latter 

continuous with the pedicel of the second spikelet, 5-13 mm 

long, often slightly exceeding the pedicel of the first spikelet, 

and bearing a rudimentary or fully developed spikelet in robust 

inflorescences; branching of partial inflorescences reiterating 

in a scorpioid cyme-like manner to produce up to 3 fully 
6 SMITHSONIAN CONTRIBUTIOSS TO BOTANY 

FIGURE 1.-Field photographs of Streprochaeta and Anomochloa: a, fruiting clump of S. spicata subsp. spicafa 

on Barro Colorado Island, Panama (note tangled, pendent masses of pseudospikelets); b, Habit of A. marantoidea, 

Bahia, Brazil (site of collection of Calderdn ef al. 2381), showing leaf blades borne at different heights and in 

different orientations due to varying lengths of the leaf sheaths and pseudopetioles. Photographs by Judziewicz 
NUMBER 68 7 

FIGURE 2.-Field photographs of Strepfochaefa and Anomochloa: a, upper leaves and inflorescence of S. 

sodiroana, La Selva, Costa Rica. A. marantoidea, Bahia, Brazil (site of collection of Calderdn ef al. 2381): b, 

inflorescence during late phase of flowering, showing exserted stamens (note the varying lengths of the leaf 

pseudopetioles and the cupped bases of the expanded portion of the leaf blades); c, inflorescence during early 

phase of flowering, showing solitary stigmas exserted from the comiculate upper spikelet bracts; d, inflorescence 

as it appears among the foliage as viewed from the "back" side (a few stigmas visible). Photographs by 

Judziewicz. 
8 SMITHSONIAN COSTRIBUTIONS TO BOTASY 

developed spikelets and 2 progressively smaller rudimentary 

spikelets, each successive lateral branch subtended by an ovate, 

keeled, scarious bract whose midrib nests with those of 

successive lower and higher subtending bracts, and the axis of 

each branch oriented so that the smaller (lower) member of the 

2 bracteoles of a given branch is positioned directly behind 

(abaxial to) the keel of the bract subtending the branch of the 

next highest order. 

Spikelets terminal, I-flowered, bisexual, deciduous from 

pedicels at maturity, consisting of a deciduous lower bract 

separated by a cylindrical internode from a persistent upper 

bract that encloses the floret. 

Lower spikelet bract 10-15 mm long, broadly lanceolate, 

rounded on the back below, somewhat carinate near the tip, 

green, 10-17-nerved, conspicuously cross-veined, the apex 

with hyaline, ciliate margins, at length deciduous, separated 

from the upper spikelet bract by an indurate, whitish, slightly 

obconic intern0d.e 3-4 mm long and 2.5-3.5 mm in diameter, 

this glabrous or with scattered cilia above, at length deciduous 

from lower spikelet bract and summit of pedicel along with the 

persistent upper spikelet bract and its enclosed caryopsis. 

Upper spikelet bract on the opposite side of the cylindrical 

internode of the lower spikelet bract, consisting of an ovoid 

body surmounted by a linear horn-like appendage (corniculum): body of upper bract 9-13 mm long, coriaceous at 

maturity, whitish, densely pubescent with prickles and clear 

hairs about 1 mm long, the margins meeting and strongly 

overlapping and locking with one another (except near the 

summit at anthesis), the venation inconspicuous externally, 

consisting of 4-6 irregularly spaced principal nerves (including 

a midnerve only slightly more conspicuous than the main 

lateral nerves) and 5-8 minor nerves, the former not visible 

on the outer surface of the body but visible as ridges on the 

interior surface; corniculum 13-18 mm long, -1-2 mm wide 

(often slightly wider near the summit), firmly membranous, 

finely pubescent, slightly grooved, slightly curved and 

protruding from the lower spikelet bract, at length deciduous. 

Perigonate annulus closely surrounding base of andrecium, 

consisting of a continuous fringe of brown cilia 0.5-2 mm tall 

borne on the summit of a low membranous ring. 

Andrecium of 4 stamens (occasionally the rudiment of a 5th 

present), these extruded from between the upper margins of the 

body of the upper spikelet bract at anthesis: filaments free, to 

2 cm long, 2 mm wide, succulent, white, the anthers 3-5 mm 

long, white, elliptic-sagittate, attached to the filaments in such 

a way that the connective surrounds the summit of the filament 

without fusing to it €or 0.4-0.7 mm; thecae introrse, facing the 

center of the andrecial circle. 

Gynecium with ovary stout, ellipsoid, 3-4 mm long and 1-2 

mm wide, oblong-pyramidal, obliquely tipped, glabrous: style 

and stigma 1, the latter papillose, white, exiting through the 

open tip of the corniculum and extending up to 1 cm beyond 

it, lax. 

Caryopsis oblong-rectangular, laterally compressed, up to 

-10 mm long, 2.5 mm wide, and 4 mm deep (in profile), 

glabrous, the summit of the style persistent as a short, folded, 

oblique beak: hilum inconspicuous, a shallow groove extending nearly the full length of the grain; pericarp thin, yellowish 

brown: endosperm mealy; embryo oblique-basal, large, up to 

2.7 mm tall and 1.8 mm wide. 

DISTRIBUTION.-Known only from wet, lowland tropical 

forests in the Municipio of Una, Bahia, Brazil. 

ADDITIONAL SPECIMENS SEEN.-(Because of the rarity of 

this species, the specimen labels are quoted in their entirety to 

avoid any future confusion.) BRAZIL. Specimens from the type 

plant (or descendents) were cultivated as late as 1866 (K!, 

fragment US ex L, W!). Municipio de Una: Primary forest on 

steep (45") rocky slope bordering cacao plantation, altitude 

180-200 m, old inflorescences, 21 Apr 1976, C.E. Calderdn, 

TS. dos Santos, and L.B. de Oliveira 2381 (CEPEC, IBGE, 

K, LE, RB, US 13 sheets], WE), 11 Jul 1978, old 

inflorescences, TS. dos Santos and L.A. Mattos da Silva 3236 

(CEPEC, K, MO), 20 Jan 1982, sterile, only a few plants in old 

fruit, V.C. Hollowell, TS. dos Santos and A.M. de Carvalho 

3000 (CEPEC, F, ISC, R, SI, UC, US, W), 3001 (B, P), 3002 

(INPA), 3003 (SP), 3004 (G), 18 Oct 1983, in all stages of 

flowering and fruiting, TS. dos Santos, G. Martinelli, and 

TR. Soderstrom 3880 (CANB, CEPEC, NY, RB, US), 21 Feb 

1986, all sterile, E.J. Judziewicz and TS. dos Santos s.n. (US), 

12 Mar 1986, most plants sterile, E.J. Judziewicz and TS. dos 

Santos s.n. (US); Municipio de Una, disturbed primary forest 

on 30" rocky slopes, altitude 160-180 m; 21 Feb 1986, all 

sterile, TS. dos Santos and E.J. Judziewicz 4111 (CEPEC), 

12 Mar 1986, all sterile, TS. dos Santos and E.J. Judziewicz 

4266 (CEPEC, US; living plants cultivated at CEPEC and US). 

VOUCHER SPECIMENS FOR ANATOMICAL STUDIES .-Brazil: 

Calderon, dos Santos, and Oliveira 2381 (US) (leaves); dos 

Santos, Martinelli, and Soderstrom 3880 (US) (leaves, 

inflorescence, spikelets, starch grains, embryos). 

DIscUssIox.-The two localities at which Anomochloa 

marantoidea grows are humid, tall forests on the steep, rocky 

(with granite boulders), lowermost slopes of the low mountains 

west of Una. At each site the area throughout which the plants 

grow consists of only a hectare or two, and only about 90 

individual plants were counted at any one station. Individuals 

growing in treefall gaps, partial shade, or forest edges are 

much smaller than those growing in dense shade. Visits to the 

extant sites from January through April (1976, 1982, 1986) 

have revealed plants with mostly old infructescences and only 

a few in flower. The October 1983 visit by Talmon dos Santos 

et al. revealed the 1976 colony in all stages of flowering and 

fruiting, but dos Santos (pers. comm., 1986) indicates that the 

plants usually bloom during the height of the local rainy season 

during June and July. 

Anomochloa marantoidea is the only species in its genus 

and tribe. Because of its rarity (and because the species is not 

well established in cultivation) we are not citing here the exact 

collection localities of the two known populations: this 

information is available in the files of the McClure Bamboo 

Library, Department of Botany, National Museum of Natural 
NUMBER 68 9 

History, Smithsonian Institution. Unfortunately most other 

potentially suitable sites for the species in the Una region have 

been destroyed in recent years through increased planting of 

cacao. Because only about 30 herbarium sheets exist we urge 

that anyone visiting the sites refrain from making further 

gatherings. 

FIGURE 3.-Anomochloa marantoidea: a, habit, showing leaf blades borne on leaf sheaths and pseudopetioles 

of varying lengths (X 0.22); b, inflorescence terminating culm with uppermost subtending leaf, the lowest leaves 

removed (X 0.22); c, upper portion of pseudopetiole and base of leaf blade showing upper pulvinus, adaxial view 

(X 1.72); d, upper portion of pseudopetiole and base of leaf blade showing upper pulvinus, abaxial view (X 

1.72); e, inner (adaxial) view andf, side view of summit of sheath and lower portion of pseudopetiole showing 

lower pulvinus and ciliate inner ligule (x 1.72); g, portion of leaf blade, abaxial surface showing transverse 

veinlets (x 1.72). (a and g based on Cafderon et af. 2381, b-fon dos Sanfos ef af. 3880, both from Brazil.) 

Illustration by Alice R. Tangerini. 
10 

n 0 P 

SMITHSONIAN CONTRIBUTIONS TO BOTANY 
NUMBER 68 11 

FIGURE 4 (lef).-Details of partial inflorescences and spikelets of Anomochloa marantoidea: a, portion of 

inflorescence showing the lowest and next to lowest partial inflorescences (note reduced leaf blade on bract 

subtending lowest partial inflorescence) (x 1.59). Base of partial inflorescence, the bract subtending the partial 

inflorescence removed (x 3.18): b, ventral view; c, dorsal view, showing keeled, nested bracts that subtend each 

successive branch. d-J Variation in bract that subtends each lateral branch (x 3.18); g, basal portion of primary 

axis, showing pair of small, lower (left) and large, upper (right) bracteoles at base (subtending bract between 

bracteoles and axis removed) (x 3.18); h, variation in the small bracteole found as the first appendage on each 

successive lateral branch (X 6.36); i, variation in the large bracteole found as the second appendage of each 

successive lateral branch (X 6.36); j, spikelet showing deciduous lower bract and pedicelled upper bract (the 

comiculum fallen from the latter) (x 3.18). Caryopsis (x 4.77): k, side view, showing oblique beak; 1, ventral 

view. showing linear hilum; m, dorsal view. n, Portion of spikelet (upper bract partially dissected away) showing 

ovary surrounded by perigonate annulus and with anomalous bract found in one spikelet (stamens removed) (x 

6.36), o, lower spikelet bract, adaxial view (X 3.18); p, spikelet, side view showing comiculate upper bract 

embraced by lower bract (note exserted stigma) (X 3.18); q, longitudinal section of spikelet (lower bract removed), 

with thickened internode supporting upper bract, perigonate annulus, stamens, and gynecium (x 3.18); r, anther, 

adaxial view (X 6.36); s, anther, abaxial view (x 6.36); t, spikelet (lower bract removed) at male flowering stage, 

showing the stamens emerging from between the margins of the summit of the body of the upper bract (x 3.18). 

(Based on dos Santos et al. 3880, Brazil.) Illustration by Alice R. Tangerini. 

FIGURE 5.-Transverse sections of sheaths and pseudopetiolar regions of leaves of Anomochloa and 

Streptochaeta. A. marantoidea (Calderdn et al. 2381): a, leaf sheath showing prominently winged margins and 

hollow body; b, lower pulvinus, showing smaller sheath margin wings and ciliate inner ligule (arrow); c, upper 

pulvinus as it expands into the blade, showing complex vasculature (adaxial epidermis on right). d, Pulvinus of 

S. spicala subsp. spicata (Calderdn 2046, Brazil), showing complex vasculature and pubescent adaxial surface 

below. Scale bar: a = 400 pm; b-d = 250 pm. 
12 SMITHSONIAN CONTRIBUTIOSS TO BOTANY 

FIGURE 6.--Leaf epidermides of Anomochloa marantoidea: a,b, adaxial epidermis, showing buUiform cells, 

crescentic silica/cork cell pairs, and isolated vertical-crenate silica cells; c, abaxial epidermis (note scattered 

prickles and bicellular microhairs; basal cell only intact); d, bicellular microhairs from abaxial epidermis (note 

constricted basal cell, arrow). Abbreviations: bm = bicellular microhair, co = costal silica cell; is = intercostal 

isolated silica cell; ip = intercostal paired silica cell; pr = prickle. Scale bar: a,c = 100 lm; b = 25 p; d = 30 

pm. (Based on Calderon et al. 2381, Brazil.) 

MORPHOLOGY- ANATOMY 

Culm and Leaf Sheath 

The culm of Anomochloa marantoidea is solid. The leaf 

sheaths are hollow with a large lacuna and prominent winged 

margins (Figure 5a), which embrace successive leaf sheath 

bodies. The marginal wings have about five vascular bundles 

and are often inrolled in a scroll-like fashion, The adaxial side 

of the leaf sheath is thicker and has several superposed tiers 

of small vascular bundles. 

Toward the summit of the sheath its marginal wings narrow 

and approach each other, and the summit of the sheath and 

lower pulvinus are nearly elliptical (Figure %).The sheath 

becomes solid in the area of the lower pulvinus for a few 

millimeters, but the vascular bundles still consist of a circle 

of approximately 10 to 12 large bundles with a roughly 

alternating circle of small vascular bundles just interior to them. 

Continuing acropetally through the lower pulvinus, these 

smaller vascular bundles and some of the larger ones contribute 

to a complex plexus in the center of the sheath. 

Ligule and Pseudopetiole 

No external ligule is present; the internal ligule is present 

as a fringe of ciliate hairs. At the summit of the lower pulvinus 

the pseudopetiole begins; again there is a lacuna in its center, 

but not so large as in the leaf sheath. The body of the 

pseudopetiole is V-shaped in cross-section. 

Pulvini 

In cross-section the upper pulvinus is slightly V-shaped, 

with the trough of the V on the adaxial surface. The ground 
NUMBER 68 13 

tissue consists of large parenchyma cells. The epidermis is 

sparsely papillate and pubescent. The main vascularization 

consists of a V-shape arch of bundles near the abaxial 

epidermis. These bundles are connected, or nearly so, to that 

epidermis by sclerenchyma caps. Subjacent to the adaxial 

surface are 5 to 8 sclerenchymatous areas that lack vascular 

bundles. The area between the adaxial epidermis and the main 

arch of vascular bundles consists of parenchyma cells in which 

are embedded about 10 small vascular bundles in a complex 

pattern. 

At its base the pulvinus encloses a large block of 

sclerenchyma buried a few cells beneath the adaxial epidermis 

(Figure 5c). Farther up, this block of cells approaches the 

epidermis and is contiguous with a broad, shallow, sclerenchyma plate covering the top of the adaxial midrib (Figure 

74. Toward the base of the lamina the adaxial midrib appears 

abruptly and soon takes on its characteristic square or anvil 

shape. 

Leaf-blade Anatomy 

TRANSVERSEECTION (Figure 7d-g).-Outline: blade flat, 

expanded (except near cup-like base), the epidermides nearly 

straight, the margins rounded to slightly acute. Midrib outline: 

distinctive, projecting both adaxially and abaxially; adaxial 

projection in lower 2/3 of the blade anvil- or keystone-shaped, 

narrowed at the base and with a broad, flat, top with margins 

that slightly overhang the lamina (this keel reduced to merely 

an inverted U-shape in the uppermost l/3 of the lamina); abaxial 

projection less prominent, low dome-shaped. Midrib vasculalure: complex in well-developed blades, with at least two tiers 

of vascular bundles; one large, median, first-order bundle with 

a lysigenous cavity and a pair of metaxylem vessels always 

present subjacent to the abaxial epidermis, this not flanked by 

any smaller bundles; several third-order vascular bundles 

present in adaxial half of the midrib, characteristically in a 

crude T- or Y-shaped pattern, with the base of the Y or T in 

about the center of the midrib. Midrib sclerenchyma: in two 

plates, one on the adaxial keel, relatively shallow (5-8 cells 

wide), and unconnected to any of the subjacent minor vascular 

bundles; the other on the abaxial keel deeper (-8-12 cells 

wide), more well developed, and partially surrounding the 

median vascular bundle, with the sclerenchyma continuous 

with the bundle sheath. Vascular bundle arrangement in the 

lamina: all bundles closer to the abaxial than adaxial epidermis. 

Primary vascular bundles: ovate in outline; double sheath 

present, the outer sheath of large, thin-walled, inflated cells 

with few plastids, complete on the adaxial side and often with 

a small extension to the adaxial sclerenchyma cap, but 

interrupted on the abaxial side, where interrupted by the 

sclerenchyma of the abaxial bundle cap; inner sheath of two 

complete rows of narrow, achlorophyllous, thick-walled cells; 

lysigenous cavity and two metaxylem vessels present; adaxial 

sclerenchyma cap squarish or inverted triangular, 10-17-celled, 

abaxial sclerenchyma cap narrow, horizontal, about 15-20- 

celled. Third-order vascular bundles: somewhat rectangular 

in outline; double sheath present, similar to that of the 

first-order vascular bundles, but adaxial outer bundle sheath 

extension never developed and abaxial sclerenchymatous 

interruption of the outer sheath only one cell wide; inner bundle 

sheath one or two cell-layers thick; adaxial sclerenchyma cap 

small, usually inverted-triangular, consisting of (2-) 5-1 2 cells, 

the abaxial cap of 8-14 cells. Intercostal sclerenchyma: absent. 

Mesophyll: chlorenchyma not radiate, consisting of one layer 

of cells immediately subjacent to each epidermis on either side 

of inflated fusoid cells, each one cell-layer thick, and separated 

by inflated fusoid cells; adaxial chlorenchyma rectangular, 

horizontal, the cells with several moderately developed arms 

projecting inward towards the fusoid cells; abaxial chlorenchyma 

cells less conspicuous than adaxial layer, narrowly rectangular 

and lacking any projections; fusoid cells well developed, 

rectangular, adjacent fusoid cells separated by a well-developed 

chlorenchymatous column 1-3 cells wide. 

ABAXIAL EPIDERMIS (Figure Bc,d).-Costal and intercostal 

zones well differentiated. Intercostal long cells: homogeneous, 

rectangular (length:width, 4-6: l), with strongly sinuous walls; 

in well-developed cells the sinuations themselves undulating. 

Stomata: in 1-3 short, interrupted rows along each side of the 

costal zones, each short row staggered so that it continues 

where the last row terminated; subsidiary cells low domeshaped to slightly triangular; stomates separated by 1(-3) long 

cells. Bulliform cells: absent. Papillae: absent. Prickle hairs: 

fairly common in intercostal zones; base greatly inflated, tip 

small, narrow, sharp; usually paired with a cork cell. 

Macrohairs: absent. Microhairs: scattered throughout intercostal zone between the stornatal regions; apparently bicellular; 

basal cell 40-50 pm long, cylindrical, relatively thick-walled, 

with an apparent constriction near the base; apical cell narrowly 

ellipsoid, 45-65 pm long, tapering to a blunt tip, thin-walled 

and easily deflated; total length of microhair 90-1 15 pm. Short 

cells: abundant, typically in pairs (silicalcork), these alternating 

with the long cells; cork cells crescent- or kidney-shaped, 

embracing a similarly shaped but slightly smaller silica cell; 

occasionally, solitary short cells (apparently cork cells) 

alternating with the long cells in the stomatal region. Costal 

cells: in rows of 24, consisting of modified, long-rectangular 

(length:width, -10: 1) long cells separated by short to long (2-8 

individual cells) rows of squarish silica cells; cork cells rare 

or absent. 

ADAXIAL EPIDERMIS (Figure &).-Basically similar to the 

abaxial epidermis. Bulliform cells: in 3 or 4 rows, covering 

about l/4 of the intercostal zones, well developed and distinct 

from typical long cells, square to rectangular (length:width, 

1-3:1), with moderately sinuous walls; not alternating with any 

other cell type. Intercostal long cells: rectangular (1ength:width 

34:1), strongly sinuous, alternating with short cell pairs. 

Papillae: absent. Prickles: not seen. Macrohairs: absent. 

Microhairs: extremely rare, only one seen. Short cells: similar 

to those of abaxial epidermis. Silica cells: occasional to fairly 

common in intercostal zones, interpolated between adjacent 
14 SMITIISOSIAN COSTRIBUTIONS TO BOTANY 

FIGURE 7.-Transverse sections of leaf blades of Streptochaeta sodirwna (ax) and Anomochloa marantoidea 

(d-g) (in all cases the adaxial epidermis faces upwards): S. sodirwna (Soderstrom 1205): a, characteristic 

midrib with its complex vasculature; b, detail of fusoid cell and primary vascular bundle in the lamina: c, detail 

of lamina showing minor vascular bundle, fusoid cells, and primary vascular bundle. A. marantoidea (Calderon 

et al. 2381, Brazil): d, section of lamina showing minor vascular bundle, fusoid cells, and primary vascular 

bundle; e,g, midrib section from a robust leaf, showing characteristic shape and complex vasculature;f, section 

of lamina including midrib, cut from a small leaf. Scale bar: a,c-e = 100 p; b = 50 p;f= 200; g = 250 pm. 

long cells in the same row, and protruding above and below subsidiary cells generally more triangular than those of abaxial 

that row halfway into the rows of long cells above and below epidermis. Costal cells: similar to those of the abaxial 

it; consisting of a vertical, elliptic cell enclosing a crenate silica epidermis, but silica cells tending to be rounder. 

body. Stomata: occasional near veins, in short irregular rows; 
.\'UMBER 68 15 

Inflorescence 

In the above description .of the inflorescence and spikelets 

of Anomochloa marantoidea we have chosen not to give any 

formal morphological interpretations of the components of the 

partial inflorescences, spikelet bracts, and perigonate annulus 

at this point. We do wish to elaborate on the complex patterns 

of branching and bract disposition in the inflorescence, features 

that do not lend themselves well to a formal taxonomic 

description (Figures 4, 8, 9, 15). The structure of the partial 

inflorescence in the following robust individual is typical of 

all other individual partial inflorescences examined in the 

species. 

The rachis of the inflorescence always terminates in a fully 

developed spikelet (Figure 15), which is not associated with 

any rudimentary spikelets or prolongation of the rachis. Below 

the terminal spikelet are a series of 4-7 alternating lanceolate, 

chlorophyllous, foliaceous bracts spaced along the rachis. The 

lowest of these bracts, which, unlike the upper ones, often bears 

a reduced, pseudopetiolate leaf blade (Figure 4a), is frequently 

separated from the second lowest by an exposed portion of the 

rachis several centimeters long. Each of these prominent 

subtending bracts, which we shall refer to as "general bracts" 

(after the designation "bractks generales" of Brongniart), 

subtends a partial inflorescence bearing from 1 to 3 fully 

developed and 1 or 2 rudimentary spikelets (Figure 4a). Figure 

4 illustrates a partial inflorescence taken from a robust 

inflorescence. The general bract subtends the primary axis of 

the lateral branch, which terminates in a fully developed 

spikelet. Near the base of the primary axis, on the side nearest 

the rachis, is usually borne a pair of delicate unequal bracteoles, 

with the smaller bracteole borne on a slightly lower level 

(Figure 4g) than the larger bracteole. The bracteoles are 

separated by about 120" with respect to the center of the axis 

that bears them. 

The lower bracteole of this pair is narrowly linear (Figure 

4h) while the other is broadly lanceolate and strongly keeled 

(Figure 44. Both bracteoles lack any vascularization and are 

hyaline and covered, especially in the upper portion, with 

brown cilia. Slightly above them on the primary axis of the 

branching system is a bract (Figure 4d-f) that subtends a 

secondary axis. The smaller of the two bracteoles just discussed 

is positioned near the keel of this bract (Figure 4c), which is 

ovate, hyaline, and has a well-developed midrib containing a 

vascular bundle. Its keel is positioned at right angles with 

respect to a line drawn from the center of the rachis through 

the center of the successive axes of the lateral inflorescence. 

As in the primary axis, the secondary axis subtended by the 

bract terminates in a fully developed spikelet and bears a pair 

of delicate, unequal bracteoles from near its base on the side 

facing the rachis. The smaller member is borne on a slightly 

lower level than the larger. Again, the members of the bracteole 

pair are separated by about 120" and tipped with a fringe of 

brown cilia. Above these bracteoles on the secondary axis is 

situated an ovate, keeled bract subtending the tertiary axis of 

the partial inflorescence. Like the preceding branch-subtending 

bract, this subtending bract is rotated about 90" with respect 

to a line connecting the rachis and successive lateral branches. 

Because of this its keel appears to be nested within the keel 

of the preceding branch-subtending bract (Figure 4c). 

In the specimen examined (dos Santos et al. 3880) the 

tertiary axis emanating from the axil of this subtending bract 

also terminates in a fully developed spikelet, bears near its 

base a pair of unequal bracteoles with the smaller bracteole 

arising on a slightly lower level, and above these bracteoles 

bears a keeled bract (whose keel nests with the keels of the 

bracts subtending the secondary and tertiary axes) that subtends 

a fourth-degree axis. The fourth-degree axis of the partial 

inflorescence terminates in a small spikelet containing a 

rudimentary gynecium and four stamens and bears a pair of 

tiny unequal bracteoles attached at nearly the same level near 

its base, and above these bracteoles a small keeled bract that 

subtends an axis bearing two tiny bracteoles as its first 

appendages and terminating in a tiny, rudimentary fifth 

spikelet. 

Each axis in the branching system terminates in a spikelet 

and bears near its base on the adaxial side a pair of delicate 

bracteoles. The smaller member of the pair is borne on a 

slightly lower level and is positioned near the keel of the bract 

subtending the next axis of the branching system (Figure 4). 

The larger bracteole is lanceolate, keeled, and is separated from 

the smaller bracteole by about 120" with respect to the axis 

that bears it. The bracteole pair members are tipped with a 

fringe of brown cilia and lack any vascular bundles. The bracts 

actually subtending each successive lateral axis of the 

branching system are much larger than the bracteoles and are 

ovate, scarious, and keeled (Figure 4d-f. In a robust partial 

inflorescence the keels of successive subtending bracts are 

nested at an angle of 90" with respect to a line drawn from the 

center of the rachis through the centers of successive lateral 

axes. The bracteole pair members of successive axes are also 

nested to the extent that all large bracteole pair members are 

aligned on one side of the partial inflorescence (Figure 46) 

while all small bracteoles are aligned on nearly the opposite 

side of the partial inflorescence. The smaller member of the 

bracteole pair arises slightly lower on the axis than the larger 

member, and the pair members are always completely separate 

from each other, even at their bases. 

The inflorescence of Anomochloa marantoidea, then, is 

qped with a spikelet and bears on its axis alternating partial 

inflorescences, each of these subtended by a prominent general 

bract that gives the inflorescence its marantaceous aspect. The 

inflorescence is laterally compressed and has a quite different 

appearance depending on which side is viewed. From one side 

all that is seen are the overlapping general bracts subtending 

each partial inflorescence (Figure 36). But viewed from the 

opposite side many features are observed (Figure 26,c): the 

general bracts subtending each successive partial inflorescence 

are visible but so are the upper portions of one or two of the 

spikelets in each partial inflorescence. Typically the upper 
16 SMITHSONIAN COSTRIBUTIONS TO BOTANY 

FIGURE 8.-Acropetal serial transverse sections through a partial inflorescence of Anomochloa marantoidea: a, 

rachis (above) and pedicel of first spikelet (below) enclosed by the “general bract” (B); b, emergence of pedicel 

of second spikelet (below); c, pedicel of second spikelet completely free from pedicel of first spikelet; d, 

beginning of emergence of pedicel of third spikelet. Abbreviations: B = bracts subtending successive branches 

of the partial inflorescence; b(1,2) = first or second bracteoles on each successive lateral branch; P(l-3) = 

successive lateral branches, terminating in a spikelet pedicel; R = rachis. (Based on dos Santos et al. 3880, 

Brazil). Scale bar: 500 pm for all sections. 
NUMBER 68 17 

FIGURE 9.-Acropetal serial transverse sections through a partial inflorescence of Anomochloa muranfoidea: a, 

pedicels of first three spikelets with pedicel of rudimentary fourth spikelet emerging; b, rudimentary third 

spikelet; c, detail of o; d, detail of 6, showing rudimentary third spikelet with three rudimentary stamens 

surrounding the rudimentary gynecium. Abbreviations: B = bracts subtending successive branches of the partial 

inflorescence; b( 1,2) = first or second bracteoles on each successive lateral branch; gy = gynecium; LSB = lower 

spikelet bract; P(1-4) = successive lateral branches terminating in a spikelet pedicel; st = stamen; USB = upper 

spikelet bract. (Based on dos Snnfos ef al. 3880, Brazil.) Scale bar: a,b = 500 pm; c,d = 150 p. 
18 SbliTIISONIAN COKTRIBUTIONS TO BOTANY 

portion of the bodics and the cornicula of the upper spikelet 

bracts are visible, as wcll as the thc upper portion of the lower 

spikelct bracts that sheath the upper bract (Figure 4a). In robust 

partial inflorcsccnccs the cornicula of the upper spikelet bracts 

of the second and third spikelets are also visible. In any case 

the cornicula of the upper spikelet bracts have a characteristic 

curvature, arching towards the partial inflorescences on the 

opposite side of the rachis. The stigmas are exserted through 

thcse cornicula (Figure 4q,t), face the same direction as that 

to which the cornicula point, and are held close to the 

inflorescence. Thus at anthcsis (see following discussion; 

Figure 2c) the stigmas are conspicuous against the green 

background of the general bracts and lower spikelet bracts. In 

contrast the stamcns, whcn cxtrudcd from bctwccn the margins 

of the body of the upper spikclct bract, arc held almost 

horiLontAly away from the body of the inflorcsccnce at a 

distance of a 1 or 2 cm (Figurc 2b). 

Spikelet 

LOWER SI’IKELBT BRACT.-This appendage bears a strong 

resemblance to the general bracts that subtend each partial 

inflorescence. It is chlorophyllous and strongly nerved, with 

many transverse veinlcts. This bract does not possess fusoid 

cclls as would a typical lamina, nor does it possess the 

laminated structure typical of the upper bract (sce “Upper 

Spikclct Bract”). 

THICKENED 1NTErLYoDn.-The internal anatomy of this 

structure is difficult to interpret bccausc the cclls were highly 

distorted in preparation. In clcarcd spikclcts and longitudinal 

sections (Figure 12b) a complcx florct stele or vascular plexus 

is found in the uppermost */s of the internode. The cpidcrmis 

of the internodc is smooth or may bear scattered brown or clear 

cilia. 

UPPER SPIKELET BRACT.-Thc upper bract is complex, and 

for convcnicnce it may be divided into two parts: the lower, 

ellipsoid body and an apical, deciduous horn or corniculum. 

The abaxial epidermis of the body is covered with a dense, 

fine indumentum of clear, l-celled ciliate macrohairs, intermixed with prickles and roundcd, silicified papillae (Figure 

10a-c). Subjacent to this is a similar layer of undifferentiated 

parenchyma cells. Just bclow this are transverscly elongated 

cells (length:width, -10: 1) with moderately thickened walls; 

this stratum is 6-8 cells thick. In some sections single 

transverse vcinlets, consisting of only a single xylcm vcsscl, 

arc apparcnt. This transverse stratum givcs the organ a 

distinctive “laminated” appearance, especially well displayed 

in paradcrmal sections (Figure 124. This laminated slructure 

continues for a millimeter or more into the summit of the 

thickened internode below the bract. Subjacent (adaxial) to the 

transversely elongated layer are the vascular bundles and 4-7 

layers of roundish, thin-walled, vertically elongated parenchyma cells, these subjacent to the adaxial epidcrmis. There 

are 5 or 6 principal vascular bundles in the upper bracts of the 

spikelets examined, each containing well-developed metaxylcm vessels and a protoxylem lacuna, and associated with a 

slight rib on the adaxial surface of the bract. The median 

vascular bundle is slightly more prominent than the others. 

Alternating with these major bundles are from 8-12 minor 

bundles, these located close to the adaxial boundary of the 

transverse cell layer. Many of these minor bundles consist of 

but a single xylem vessel. One, occasionally 2, or rarely 3 

minor bundles are situated between successive major bundles. 

The bract margins overlap strongly so that one margin retains 

a spiral- or sickle-like aspect and curls over and interlocks with 

the other, which resembles the head of a hammer (Figure 1 la). 

This tight interlocking is maintained throughout the lower 

two-thirds of thc brxt, but bccomcs looser in the upper portion 

of the body. The corniculum of the uppcr bract is covered 

externally with the same type of ciliate, transparent macrohairs 

that cover the body; internally the corniculum is 5-8-nerved. 

PERIGONATE ~NULVS (Figures lOa-c, lla-b, 12c).-The 

basal membranous part of this circular structure is only a few 

cells high and wide, and is appressed to the base of the 

filaments. The ring is complete; in acropetal serial crosssections of the spikelet it is not evident which side of the ring 

appears first; it appears to arise, along with the andrecium and 

gynecium, from the summit of the cylindrical internode 

separating the lower and upper spikelet bracts. No vascular 

bundles were detected entering or even approaching the 

perigonate ring. The dense fringe of hairs surmounting the ring 

consists of tapcring, brown (less commonly transparent), 

thin-walled, apparcntly l-cellcd cilia. These hairs vary in 

lcngth from 0.5-2 mm. Whcn cross-sectioned, thcse hairs often 

appear to break up into, or release, round brown globules. The 

hairs appear to be identical in structure to the cilia found in the 

ligular and pulvinar areas of the leaf and also on the surface 

of the upper spikelet bract. 

AYDRECICM.-h cross-sections made just below the bases 

of the filaments (Figures 10, ll), we found two large gaps on 

either side of the vascular bundle leading into the posterior 

stamen opposite the single, anterior stigma bundle (Le., on the 

side of the upper spikelet bract in which the margins overlap; 

Figure 10a). 

Several unusual structures were found in some spikelets: in 

one andrecium the base of the filament of the anterior stamen 

had a distinct lateral appendage (Figure 1 lb) that appeared to 

represent the rudiment of a fifth stamen; this rudiment was less 

than 50 pin long and bore no anther. In another spikelet the 

gap betwccn the anterior and one of the posterior lateral 

stamens was occupied by a hyaline, unvascularized linear 

(U-shaped in cross-section) appendage 5 mm long with 

strongly brown-ciliate margins (Figure 4n). The connective of 

the anthers completely encircles but does not fuse with the 

summit of the filaments for a short distance (0.4-0.7 mm) near 

the base of the anthers (Figures lld, 12a). In cross-sections 

through their lower and middle portions, the anthers have an 

introrse aspect because their thecae are rotated forward slightly 
NUMBER 68 19 

FIGURE 10.-Transverse sections of spikelet of Anomochlua and pseudospikelet of Streptochela. A. 

marantoidea (lower spikelet bract not sectioned) (dos Santus et al. 3880., Brazil): a, near base, showing flower 

still partially attachcd to base of uppcr spikelct bract, and perigonate annulus and filaments starting to separate 

from the ovary; b, detail of spikelet showing perigonate annulus, three posterior filaments, and portion of ovary; 

c, detail of spikelet showing laminated anatomy of upper spikelet bract (right), with perigonate annulus and part 

of ovary (left). d, Pseudospikelet of S. spicata subsp. spicata (Soderstrum and Cafderon 1861, Brazil), showing 

overlapping bracts X through XI1 surrounding the flower; flower composed of six stamens surrounding an ovary 

with three stigmatic vascular bundles (arrows); note attachment of ovule on right side of ovary. Abbreviations: 

B = pseudospikelet bracts X-XII; gy = gynecium; per = perigonate annulus; st = stamen; svt = stigmatic vascular 

trace; usb = upper spikclet bract. Scale bar: a = 300 pm; b-d = 100 pn. 
20 SMITHSONIAN CONTRIBUTIOKS TO BOTANY 

FIGURE 1 1.-Transverse sections of spikelet of Anomochloa marantoidea: a, characteristic interlocking margins 

of the upper splkelet bract; b, rudimentary 5th stamen located between anterior stamen (upper) and one of the 

posterior lateral stamens (lower); c, detail of ovary showing absence of posterior lateral stigmatic vascular traces; 

anterior stamen at top, posterior at lower left; d, detail of stamen showing filament unfused to connective and 

the pollen sacs rotated towards the adaxial side of the stamen (upper right in this section); note also the laminated 

structure of the upper spikelet bract (lower). Abbreviations: en = connective; fi = filament; gy = gynecium; ovt 

= ovular (posterior) vascular trace; ow = ovule; per = perigonate annulus; rs = rudimentary stamen; st = stamen; 

svt = stigmatic (anterior) vascular trace; usb = upper spikelet bract.(Based on dos Sanros et al. 3880, Brazil.) 

Scale bar: 100 pm for all sections. 
NUMBER 68 21 

FIGURE 12.--longitudmal sections of spikelet of Anomochloa muruntoidea: u, laminated structure of upper 

spikelct bract (left) and filament attachcd to anther (right); b, detail of gynecium (note the vascular plexus at 

summit of internode below); c, detail of upper spikelet bract, perigonate annulus, and filament; d, oblique 

paradermal section of upper splkclet bract showing laminated structure. Abbreviations: an = anther, fi =filament; 

gy = gynccium; ii = inncr integument; nu = nucellus; oi = outer integument; ovt = ovular vascular trace; per = 

pcrigonate annulus; pl = vascular plexus at base of flower, re = internode between lower and upper spikelet 

bracts; svt = stigmatic vascular trace; usb = upper spikelet bract. (All based on doJ Suntos ef ~l. 3880, Brazil.) 

Scale bar: u-c = 100 pm; d = 25 p. 
22 SMITHSONIANCONTRIBUTIONS TO BOTANY 

and face the center of the andrccial circle (Figure 116). In the 

upper portion of the anther, however, the thecae have a more 

lateral arrangement on both sides of the connective. 

GYNEC1UM.-Cross-sections of the gynecium revealed the 

presence of two vascular bundles, one located on the posterior 

side (i.e., on that side at which the ovule is attached) of the 

ovary and leading into the ovule (ovular strand) and one located 

on the anterior side of the ovary and leading into the style 

(Figures 10a, llb,c). Longitudinal sections of the ovary 

revealed the presence of two integuments surrounding the 

megasporangium (Figure 12b), which is attached to the ovary 

wall near the apex of the ovular cavity. The style with its single 

vascular bundle tapers apically into a single papillose stigma. 

Fruit 

CARYOPS1S.-The caryopsis, which is tightly invested by 

the uppcr spikelet bract at maturity, is elongate-prismatic with 

a slightly oblique beak and a shallow, inconspicuous linear 

hilum. The embryo is oblique-basal and is hidden by the 

papery, light brown pcricarp. 

STARCH GRAINS.-The endosperm of the mature caryopsis 

is mealy, and the starch grains are highly compound. 

Approximately 50-100 ellipsoidal grains occur in each cell and 

each grain ranges in size from 10-20 pm in diameter. Each 

grain is composed of 20-50 sharply angular granules and the 

granules range in size from 2.5-4.5 prn in diameter. 

EMBRYO.-In median sagittal scction (Figure 13c,d) the 

embryo exhibits a massive scutellum, an epiblast, and a fairly 

inconspicuous cldt bctween the lowcr part of the scutcllum 

and thc colcorhiza. Due to the promincnce of the scutellum and 

the relative inconspicuousness of the colcoptile and coleorhiza 

this cleft appears not basal but is situated about l/3 of the way 

up the abaxial side of the embryo. The coleoptilar-coleorhizal 

axis is rotated about 60” from the vertical, and no internode 

(mesocotyl) is prcscnt between the divergence of the vascular 

traces to the scutellar and coleoptilar nodes. In acropetal series 

of transverse sections through the embryo (Figure 14) near the 

base of the coleoptile 5 nerves are evident, 2 being 

submarginal, 2 submedian, and 1 median. The median nerve 

is soon lost distally, appearing to merge with one of the 

submcdial ncrves. Scctions madc ncarer the middle of the 

coleoptile reveal the structure of the first embryonic leaf; it is 

3-ncrvcd, has margins that mcct but do not ovcrlap, and 

cncloscs a small sccond crnbryonic lcaf, In scctions madc still 

furthcr up the colcoptile, a distinct cleft begins to appear on 

the sidc of the colcoptile opposite the scutellum. This cleft 

broadcns until a distinct, oblique slit is observcd in the 

colcoptilc near its summit (Figure 14a, arrow). It is difficult 

to intcrpret the free margins of the coleoptile as either mceting 

without overlapping or as actually overlapping. Until near its 

apex, all four rcmaining nerves are still apparent in crosssections of the coleoptile. 

CHROMOSOMES 

The only count was made by Juan H. Hunziker (pers. 

comm.), who found n = 18, based on the following collection: 

dos Santos, Martinelli, and Soderstrom 3880. 

DISCUSSION 

Habit 

In the dense shade of the forest Anomochloa marantoidea 

is a robust, clumped plant reaching up to a meter in height 

(Figure lb). In cultivation or in treefall gaps individuals are 

much smaller; Brongniart (1851) used the adjective “humile” 

in his original description of greenhouse material. Plants of 

Anomochloa prcsent an unusual aspect in that the heights and 

orientations of successive leaf blades are regulated by several 

adaptations involving the leaf sheaths, pseudopetioles, and 

possibly the pulvini, and not by their disposition at the 

successive nodes of an elongated culm as in most grasses. The 

leaf sheaths have a nearly vertical orientation, but diverging 

from their summits by 45” or more are long pseudopetioles of 

varying lengths, with those of the upper leaves much longer 

than those of the lower. The variable lengths of the leaf sheaths 

and pseudopetioles may ensure that the blades are held at 

differing heights above the soil. The leaf sheaths are unusual 

in that they are consistently hollow. The base of the expanded 

portion of the lamina is slightly cordate and cupped upwards 

(Figures 2b, 3), a trait Anomochloa shares with other 

large-leaved umbrophilic herbaceous bamboos, such as the 

Bahian endcmic Sucrea monophylla (Bambusoideae: Olyreae) 

and the African Puelia schumanniana (Bambusoideae: Puelieae), 

as well as the broad-leaved Ichnanthus grandifolius (Panicoideae: Paniceae). Although Brongniart (1851) described the 

leaf blades as subarticulating we found no evidence that they 

are deciduous. The hollow leaf sheaths and pseudopetioles of 

Anomochloa may be unique in the family. 

Diurnal sleep movements of the leaf blades of the type 

observed in certain olyroid herbaceous bamboos (Arberella, 

Cryptochloa, Lithachne, Raddia; cf. Soderstrom, 1980) have 

not been seen in Anomochloa. However, in mature plants the 

blades have quite different orientations on the same shoot: 

some are held horizontally, while others are distinctly 

descending or ascending, and the blades of successive leaves 

are not placed in a strictly opposite orientation with respect to 

one another. It may be that the pulvini, although not involved 

in diurnal movcmcnts of the blades, help determine the mature 

orientation of the lamina. Bipulvinate pseudopetioles, although 

not common in the Poaceae, are known from large-leaved 

species of the centothecoid genus Zeugites. 

Leaves 

Two features are prominent in a transverse section of a leaf 

blade (Figure 7) of Anomochloa marantoidea. First, the fusoid 
NUMBER 68 23 

FIGURE 13.-Median sagittal sections, embryos of Streptochaeta and Anomochloa: a, S. spicata subsp. spicata 

(Soderstrom and Sucre 1896, Brazil), showing poorly developed cleft between scutellum and coleorhiza (arrow); 

b, S. sodiroana (Calderon 2096, Panama), showing overlapping margins of coleoptile (arrow); c, A, marantoidea 

(dos Sanfos el al. 3880, Brazil), showing massive scutellum; d, detail of c showing abaxial position of cleft 

between coleorhiza and scutellum (arrow). Abbreviations: cp = coleoptile; cr = coleorhiza; ep = epiblast; If = 

first embryonic leaf; ra = radicle; sc = scutellum; vt = vascular trace. Scale bar: a,b,d = 100 pm; c = 25 pm. 
24 SMITHSOXIAN CONTRIBUTIONS TO BOTANY 

FIGURE 14.-Transverse sections through plumule of embryo of Anomochloa marantoidea (dos Santos et a/. 

3880, Brazil) (a through d proceeding in a downward (basipetal) direction with respect to the embryonic axis): 

u, unfused, obliquely meeting margins of coleoptile (arrow); b,c, margins of first embryonic leaf; d, entrance of 

vascular trace from scutellum, which becomes the midnerve of the coleoptile. Abbreviations: cp = c oleoptile; 

ep = epiblast; If = first embryonic leaf. Scale bar: 100 pn in all sections. 
NUMBER 68 25 

cells are large, occupying about one-half of the volume of the 

lamina (Figure 7e). And secondly, the midrib posscsscs two 

projecting keels. The adaxial keel is more prominent and has 

a strongly flattened top with edges that overhang the base 

slightly. The abaxial keel is low, dome-shaped and is associated 

with the median vascular bundlc, which lics just bclow thc 

epidermis. Small blades have mcrcly a dome-like adaxial keel, 

no abaxial kecl, and a simple vasculature with but a single 

median vascular bundle lying close to the abaxial epidermis 

(Figure 7j). 

The vascular bundles of the leaf blades of Anomochloa have 

typically bambusoid sheaths, with an outer sheath of large, 

thin-walled cells with few plastids, and an inner sheath of one 

or two layers of small, thick-walled, fibrous cells. Arm cells 

are not well developed in the mesophyll subjacent to the 

adaxial epidermis, and bulliform cells on the adaxial epidermis 

are only moderately well developed. 

The epidcrmides of Anomochloa exhibit typically bambusoid sinuous long cells. Leaf epidermal papillae, common 

in most bambusoids, are lacking in Anomochloa. The 

silica-cork cell pairs arc unusual in that both mcmbcrs arc 

vertically crcsccnt-shaped with the larger cork cell embracing 

the much smaller silica cell. The costal silica cells contain silica 

bodies that vary from round to squarish to slightly crossshaped. A third type of silica cell is found on the adaxial 

epidermis, present as large, solitary, vertically elliptical cells 

enclosing olyroid crenate silica bodies. 

The microhairs of A. marantoidea are found almost 

exclusively on the abaxial epidermis and are large, some 

attaining 115 pm in length (Figure 6b). Metcalfe (1960:28) first 

reported their presence and noted that it was difficult to find 

examples in which the distal cell had not collapsed and, thus, 

many of the hairs appeared to be unicellular. Renvoize (1985), 

using the same material as ours (Calderon et al. 2381), reported 

and illustrated anomalous short bicellular microhairs in which 

the distal cell was globose, not long and pointcd as we found 

them in undamaged hairs. Wc have bccn unable to find this 

hair type in our preparations. The basal cell (40-50 pm long) 

is cylindrical but has an apparent constriction or invagination 

approximately one-third of he way up from the base; that part 

of the cell below the constriction is conical in shape and might 

be mistaken for a separate cell. The delicate upper cell of the 

microhair (45-65 pm long) is narrowly ellipsoidal and tapers 

to a slightly pointed apex. It is rare in the bamboos for the 

upper cell to be distinctly longer than the lower one (Metcalfe, 

1960, fig. 16). This character is frequent in the panicoid 

grasses, which, however, have much smaller microhairs. 

Inflorescence 

The principal difficulty in interpretation of the inflorescence 

of Anomochloa is the highly contorted and bracteate nature of 

the partial inflorescences. If we take as a generalized ancestor 

the typical graminaceous branching pattern, we should expect 

to find a bract subtending each successive branch of the 

inflorescence; and secondly, a bikeeled bract (prophyllum) 

would be the first appendage borne on each lateral branch. In 

grasses with complex branching systems, such as many 

bamboos, this organ can be a useful “marker” in interpreting 

branching pattcrns. Instead of bicarinate bracts as the first 

appendage of each successive lateral branch, Anomochloa has 

a pair of tiny bracteoles. Brongniart, as revealed in his 

unpublished notes in the Paris Herbarium on the inflorescence 

of Anomochloa, did note the presence of these bracteoles, but 

he did not figure them in his published schematic diagram of 

a partial inflorescence (1851). Doell (1871:24) also detected 

the bracteoles (“squamulae”) and he suggested that they result 

from the separation of a single organ. He correctly placed them 

about 120’ apart between the areas of contact of the rachis and 

axis of the primary lateral branch. He also noted that they 

appear to be the result of the splitting of a single organ by the 

compression of the rachis against this lateral branch. He 

suggested that the two organs might be the result of a 

prophyllum that had been split by the pressure of the two axes 

just mcntioncd. Doc11 did not, however, observe the smaller 

bracteole pairs that were almost certainly present in the higher 

orders of branching in his partial inflorescence. While the 

position and consistent morphology of these bracteole pairs 

does suggest the possibility that they are the remnants of a 

prophyllum that has split into two portions, it should be noted 

that the bracteoles are never in actual contact, even at their 

bases, and that in dissections and in acropetal serial sections 

they appear to arise at different levels on the lateral branch. 

Also, split prophylls are not known from any other grass. 

The interpretation of the partial inflorescence of Anornochloa 

depends on how one interprets the nature of these bracteole 

pair members, which are the first appendages of each 

successive branch of the partial inflorescence. Since the smaller 

member of each bracteole pair arises slightly below the upper 

member, the formcr appcndage is best interpreted as a prophyll 

and the upper bracteole as the second appendage on the lateral 

branch, that is, simply an empty bract lacking a bud in its axil. 

The third appendage on the axis is the prominent keeled bract 

that subtends the next lateral branch. 

If this interpretation is correct, then in formal morphological 

terms each partial inflorescence could be labeled a scorpioid 

cyme (Figure 15). This was the interpretation of Brongniart 

(1851) although he did not give a detailed explanation for his 

designation. 

Spikelet 

Perhaps the best way to understand the structure of the 

spikelet ofAnomochloa is to begin examination at the apex of 

the branch bearing the flower and to proceed downward along 

this axis. For the purposes of the following discussion we will 

assume that the primitive grass had 6 stamens (arranged in 

alternating whorls of 3) and a 3-styled ovary with the vascular 
26 SMITHSONIAN CONTRIBUTIONS TO BOTANY 

FIGURE 15.4chematic of the inflorescence of Anomochloa marantoidea 

showing partial inflorescences (PI) (only those on right side fully diagrammed) 

alternating on a rachis that terminates in a spikelet. Solid dots rcpresent fully 

developed spikelets, open dots represent rudimentary spikelets. Abbreviations: 

B = bracts subtending lateral branches; b( 1.2) = first or second bracteole of a 

lateral branch. 

bundles leading to the stigmas placed altcrnatc to the thrce 

stamens of the inncr whorl. Howcvcr, it is by no mcans ccrtain 

that this supposition is correct. There is evidcnce, for example, 

that in grasses the stamens do not arise in whorls of 3, and 

that the lodicules do not all arise from a single whorl (see 

Clifford, 1987, for a review of this subject). Lacking 

developing inflorescences of Anomochloa for study we will 

draw our conclusions using conventional assumptions on the 

interpretation of the parts of the grass flower. 

GYNEC1UM.-Our observation that the ovary of Anomochloa 

marantoidea retains but a single anterior stigmatic vascular 

bundle is in accordance with the observation of Arbcr (1929) 

but not that of Schuster (1909), who figured three stigmatic 

bundles in the gynccium. The latcral posterior pair of stigmatic 

bundles present, for example, in species of Streptochaeta 

(Figure 106) is not present in Anomochloa. 

ANDREC1UM.-The flowcrs of Anomochloa muruntoidea 

consistcntly bcar four stamens. Bascd on comparison with 

other Bambusoideae we assume that the primitive state in the 

subfamily is six and that two have been lost. This idca was first 

suggcsted by Brongniart (1851), who stated that the stamens 

are arranged in a homogeneous cycle such that it is impossible 

to determine which pair had been lost. The schematic figure 

of Schuster (1909, fig. 22) of a spikelet cross-section shows 

two gaps in the andrecial ring that might pertain to the lost 

stamen pair. His figure is otherwise misleading, however, in 

that thrce stigma bundles are figurcd and the position of the 

interlocking margins of the upper spikelet bract with respect 

to the andrecium and gynecium is incorrect. In transverse 

sections madc just below the bascs of the filaments (Figure 

10a), we found two large gaps on either side of the vascular 

bundle leading into the postcrior stamcn oppositc thc single 

stigma bundle. If it is assumed that the ancestor of Anomochloa 

indeed had six stamens and three stigmas, and that the three 

stamens of the inner whorl were placed alternately with the 

three stigmatic bundles of the ovary (of which only the anterior 

remains), then it seems reasonable to conclude that these two 

gaps in the andrecium correspond to positions of the lateral 

anterior pair of stamens from the inner whorl, which have been 

lost. Arber (1929) arrived at this same hypothesis by a different 

line of reasoning. Based on her studies of the flowers of woody 

bamboos she noted that the inner whorl of stamcns was more 

liable to reduction than the outer whorl and that the posterior 

stamen of the inner whorl was less liable to reduction than the 

anterior latcral pair. Although not observing gaps in the 

andrecium base of Anomochloa she did note that the posterior 

stamen was slightly smaller than the other thrce and thus might 

correspond to a stamcn of the inncr whorl, in which casc the 

6 

PI 

PI 

4 

2 

PI 

U 

1 PI 
NUMBER 68 

two lateral anterior members of the whorl have been lost. An 

additional fact in support of the hypothesis that it is the anterior 

lateral pair of stamens that have been lost is the observation 

that in several sections of one spikelet the base of the filament 

of the anterior (outer whorl) stamen had a distinct lateral 

appendage (Figure llb) that may represent the rudiment of a 

fifth stamen (one of the anterior lateral pair of the inner whorl). 

In the specimen examined this rudiment is less than 50 pm 

long and bears no anther. Arber (1929) also pointed out that 

the stamens of Anomochloa rescmblc those of no othcr grass 

in that the bases of the anthers completely encircle but do not 

fuse with the filament for a short distance near the base of the 

former. We also found this to be the case (Figure 116). In 

cross-sections through their middle portions the anthers have 

an introrse aspect because their thecae are rotated forward 

slightly and face the center of the andrecial circle. In the upper 

portion of the anther, however, the thecae have a more lateral 

arrangement on both sides of the connective. 

PERIGONATE A”ULLJs.-completely surrounding and closely 

appressed to the base of the stamen ring is a low membrane 

bearing at its summit a dense fringe of brown cilia. Brongniart 

(185 1) called this circular structure simply a “discus annulus” 

and, although he offered no formal interpretation of it, he did 

note that lodicules (“squamulae”) are lacking in Anornochloa, 

thus implying that the ring could not represent a highly 

modified set of lodicules. Hooker (1862), Doell (1871), 

Schuster (1909), and Pilger (1954) all appear to agree with this 

interpretation although Doell (1871:24) does add in his 

description of the feature the query “perigonio?” [perianth]. 

Arber (1929) offered two suggestions as to the nature of the 

ring: it could indced represent a reduced and fused ring of 

lodiculcs (the “ciliate perigon” of her figure 52) or that it could 

represent a greatly reduced lemma. The latter interpretation 

was suggested to Arber by the condition in the pooid genus 

Lygeum in which lemmas from adjacent florets are fused into 

a tubc whose summit bears a dense fringe of hairs. Hubbard 

(1934:219) apparently was influenced by Arber’s first intcrpretation as he describes the ring as “lodicules?.” We shall call 

this structure the perigonate annulus, a term that is dcscriptive 

of its morphology and position in the spikelet but that lacks 

the interpretive implications of “pcrigon.” Bccausc thc annulus 

does have a membranous portion it might reprcsent a ring of 

reduced, fused lodicules as hinted by Doell. Grasses (e.g., 

Melica) are known that have partially to totally fused lodicules. 

These lodiculcs, however, retain discrete sets of vascular 

bundles indicating the individual nature of these organs. 

Because the pcrigonate annulus of Anomochloa is a homogeneous ring and does not have any vascular bundles entering it or 

even lcading to it, the structure is of little use in interpreting 

the nature of the upper spikelct bract that surrounds it. We are 

unable to find convincing evidcnce that it is either a reduced 

lemma, palca, ring of lodicules, or outgrowth of thc base of the 

andrecium. 

UPPER SPIKBLBT BRACT.4utside of the pcrigonate annulus, and enclosing it and the floret, is the upper spikelet bract. 

21 

Its tightly interlocked margins (Figure lla) meet on the side 

of the flower (with respect to the position of the attachment 

of the ovule to the wall of the ovary) that would correspond 

to the position of a palea in a conventional grass spikelet, and 

indeed Brongniart interpreted it as a palea. However its 

laminated structure, deciduous apical appendage, many nerves, 

and lack of an associated prolongation of the rachilla is not 

characteristic of a palea. 

THICKENED INTERNODE.-BelOW the upper bract is a 

thickened, barrel-like indurate internode that separates the 

lower from the upper spikelet bracts. 

LOWER SPIKELET BRACT.-The base of the thickened 

internode bears the lower spikelet bract, a many-nerved, 

tessellate structure that is placed alternate to the upper bract 

and alternate to the bract that subtends the branch that 

terminates in the flower. 

Brongniart (185 1) mainly based his interpretation of the 

Anomochloa spikelet on the terminal position of the flower and 

the position of the upper spikelet bract with respect to the 

stamens. He pointed out that despite the fact that the upper 

spikelet bract lacked two keels, paleas were known in the 

oryzoid grasses (e.g., Oryza) that were 3-nerved and lacked 

well-defined bicarinate keels. Given this “marker,” the lower 

bract, he argued, must represent a lemma. The oryzoid grasses 

often have reduced or absent glumes. But teratological 

evidcnce suggests that the so-called palea of Oryza is actually 

a lemma and that the true paleas in the spikelet have been lost 

(Nune z, 1968:95). Schuster (1909, fig. 23) was impressed wit

the peculiar hammer-and-sickle fit of the upper bract margins 

of Anomochloa, and turning, like Brongniart, to Oryza, he 

noted (1909:32) that the lemmas in that genus have at least 

superficially similar interlocking margins; in his interpretation, 

then, the lower bract represented a glume. Unfortunately 

Schuster’s (1909, fig. 22) schematic drawing of a cross-section 

of a spikelet Anomochloa is misleading on several counts. 

First, as already noted he figures three vascular bundles in the 

gynecium; and secondly, his floret is rotated 180” with respect 

to its true orientation within the upper spikelet bract, so that 

the missing stamen pair would appear to be the lateral posterior 

pair of the outer whorl. Still, his hypothesis that the upper bract 

rcprcscnts a lcmma is a reasonable one. One fact lending 

support to this idea is that the female lemmas of all genera of 

the Phareae, another tribe of herbaceous bamboos, possess a 

“laminated” internal structure quite similar to that found in the 

upper bract of Anomochloa (figured by Schuster (1909, fig. 

23) but first noted by Arber (1934, fig. 52); see Figures lld, 

12a,b-d). Although it is difficult to imagine that this striking 

feature was independently derived in the two groups, it may 

be noted that in the pharoids the transversely elongated cell 

layer is subjacent to the adaxial epidermis, while in 

Anomochloa the similar cell layer is subjacent to the abaxial 

epidermis. We have also observed a laminated structure in the 

culm-leaf sheaths of some woody bamboos. 

Arber (1929, fig. 52) labeled the lower and upper spikelet 

bracts and the perigonate annulus in her drawing of a 
28 SMITHSONIAN CONTRIBUTIONS TO BOTANY 

cross-section of an Anomochloa spikelet as the flowering 

glume (Icmma), palea, and ciliate pcrigon, respectively. Yet 

she was also impressed by the similarity of the perigonate 

annulus of Anomochloa to the reduced, hairy lemma found in 

the anomalous genus Lygeum. Although not claiming that the 

two groups were particularly closely related, Arber suggested 

that if the reduction of the grass lemma could definitcly proceed 

so far in Lygeum, it was not impossible for it to have proceeded 

farthcr yet in Anomochloa. Clayton and Renvoize (1986:58) 

apparcntly find this suggestion attractive as well. 

None of the three extant hypothcses has an overwhclming 

weight of evidcnce bchind it. The suggcstion of Schustcr 

(1909:32) that the two spikclct bracts be intcrpretcd as just 

bracts appears to be the most reasonable at this point. 

Developmental studies of abundant material of initiating and 

developing inflorescences of Anomochloa will be required to 

elucidate furthcr the problem of how to interpret the spikelet 

structures morc satisfactorily. For now we must tentatively 

interpret the spikclet bracts as two lateral appendages on an 

axis that terminates in the flower. The terminal position of the 

flower on the branch indicates that, as in Stipa (Clifford, 1987), 

the uppcrmost spikelet bract cannot always be correctly 

designated as a palea. 

Fruit 

The caryopsis of Anomochloa maranloidea is remarkable 

for its large size (Figurc 4k-m). Although many woody 

bamboos have larger caryopscs, among the herbaceous 

bamboos only the fruits of Olyra caudata approach those of 

Anomochloa in volume. The three available caryopses that we 

cxamincd were roughly cylindrical in shape and tightly 

invested by the upper spikelet bract at maturity. The 

oblique-basal embryo, although relatively small (as is typical 

for bambusoid grasses) when compared with the size of the 

caryopsis, is in absolute terms the largest known for any 

herbaceous bamboo. The embryo has a Reeder (1957) formula 

F+PF (Figures 13c,d, 14): there is no internode between the 

divergence of the coleoptilar and scutellar traces (F, a pooid 

[festucoid] feature); an epiblast is present (+, a pooid feature); 

therc is a cleft bctween the lowcr part of the scutellum and the 

coleorhiza (P, a panicoid feature), and the margins of the 

embryonic first leaf meet but do not overlap (F, pooid). Thus, 

except for the non-overlapping embryonic lcaf margins, 

Anomochloa has a typically bambusoid embryo formula 

(Reeder, 1962). Other bambusoid grasses are known that have 

a formula of F+PF, that is, with non-overlapping first leaf 

margins, for example Pharus mezii and P. lappulaceus (see 

Judziewicz, 1987) and the woody bamboo Alvimia (Soderstrom 

and Londono, 1988). 

Reproductive Biology 

Depending on whether or not the stigmas or stamens are 

visible the aspect of the inflorescence of Anomochloa 

marantoidea is quite different. The following preliminary 

description of anthesis is based on observations of two small 

flowering plants followed daily in Bahia, Brazil, for several 

weeks in February and March 1986. The entire flowering 

episode took approximately two weeks in these plants, which 

bloomed out of season and exhibited small inflorescences with 

only one functional spikelet in each partial inflorescence. 

The stigmas appear before the stamens, and in both plants 

the terminal spikelet (the only spikelet not borne in a partial 

inflorescence) was the first to exsert its stigma through the 

corniculum of its upper spikelet bract. A day or two later the 

stigmas of the spikelet of the lowest partial inflorescence (PI, 

in Figure 15) were exsertcd. A few days later those of the 

spikelets of the subapical partial inflorescences appeared in 

acropetal sequence (P12-P16). Several days after the last stigmas 

had been exserted, that is, about a week after the appearance 

of the first stigma, the stamens began to be extruded from 

between the margins of the upper part of the body of the upper 

spikelet bracts. The terminal spikelet extruded its stamens first. 

On the next day, the spikelet of the lowermost partial 

inflorescence extruded its stamens, and male flowering then 

proceeded upward, with the spikelet of the subapical partial 

inflorescence the last to extrude its stamens. 

Based on our field observations Anomochloa is protogynous, 

as noted by Brongniart (MI), whose figure of an inflorescence 

“au commencement de la floraison” shows all of its stigmas 

exserted but no stamens visible. This type of flowering pattern 

is frequent in the herbaceous bamboos. Several species of 

Pharus (Judziewicz, pers. obs.) and Leptaspis (collectors’ 

notes), Streptochaeta sodiroana (Judziewicz, pers. obs.) and S. 

spicata (Soderstrom, pers. obs.) all exhibit this pattern. This 

pattern was also observed by Soderstrom in the woody 

bamboo, Dendrocalamus membranaceus (Soderstrom 2660, 

US) in plants cultivated in India. 

What is the dispersal mechanism for the caryopsis of 

Anomochloa marantoidea? Unlike the Phareae, Streptochaeteae, and Streptogyneae, the spikelets and inflorescences of 

Anomochloa show no adaptations for external animal dispersal 

(Ridley, 1930:598ff; Van Der Pijl, 1982:78ff), a dispersal 

strategy that may have enabled these tribes to survive as 

widespread taxa to the present day (Soderstrom and Calderon, 

1974; Soderstrom, 1981a). The diaspore of Anomochloa 

consists of the thickened, cylindrical internode between the 

lower and upper spikelet bracts, above which is attached the 

persistent, indurate upper spikelet bract, this enclosing the large 

caryopsis (Figure 4j). Davidse (1987) has shown that the 

superficially similar internodes between the glumes and floret 

of the olyroid Cryptochloa (all species) and Olyra (some 

species) are elaisomes that at maturity contain oils that attract 

foraging ants. Davidse notes that although similar-appearing 

thickened internodes in the olyroids Arberella and Lithachne 

produce no oils, Anomochloa should be investigated for this 

feature. Unfortunately, all of the mature spikelets available for 

this study were preserved in FAA, which destroys oils. Our 

sections of the central part of the internode showed either poor 

cell preservation or lack of cellular structure. 
NUMBER 68 29 

Streptochaeta Schrader ex Nees von Esenbeck 

Streptochela Schrader ex Nees von Esenbeck, 1829536. 

HISTORY 

Streptochaeta is widely distributed in Neotropical forests 

and thus material has long been available for its study. The 

papers of Nees von Esenbeck (1829,1835,1836), Doell (1877), 

Clakovskfy(1889), Hackel (1890), Arber (1929), Page (1951), 

Dobrotvorskaya (1962), and Sodersuom (1981a) all represent 

contributions to the understanding of the inflorescence of this 

grass, long thought to be the most primitive genus in the family. 

The embryo of Streptochaeta has also been the subjcct of 

studies by Yakovlev (1950) and Reeder (1953); starch grains 

by Yakovlev (1950) and Tateoka (1962); and leaf anatomy by 

Page (1947), Metcalfe (1960), and Renvoize (1985). Because 

the genus shares certain features of the microhair, leaf midrib, 

starch grain, and embryo structure with AnomochIoa we are 

presenting here a formal study of its leaf anatomy and 

taxonomy. 

TAXONOMY 

DIAGNOSIS.-Perennial forest grasses. Culms hollow, erect, 

branched or not above; lowermost leaves consisting of 

bladeless sheaths; prophylls many-nerved, not bicarinate. 

Leaves lacking both inner and outer ligules, but with lateral 

appendages and oral setae present at the summit of the sheath; 

pseudopetiole short, terminating in a stout, appresscd-hispid, 

dark-colored pulvinus at the base of the expanded portion of 

the blade; lamina usually broad, the midrib raised on both 

surfaces (more prominently so above), the secondary lateral 

veins and transverse veinlets prominent below (abaxially) only, 

both surfaces glabrous or rarely the abaxial surface hirtellous; 

venation pattern slightly oblique, at least one primary lateral 

vein joining the midrib a few centimeters above the base of the 

lamina; uppermost leaf (or two) below the inflorescence a 

bladeless sheath(s) surrounding the developing inflorescence. 

Inflorescence a terminal spike or contracted raceme of spirally 

arranged, appressed pseudospikelets, these borne on short 

cupulate pedicels; peduncle absent to well developed; occasionally a second inflorescence produced from a bud in the 

axil of the uppermost leaf. Pseudospikelets lacking glumes, 

lemmas, paleas, and lodicules, terete, falling entire, composed 

of 11 or 12 spirally arranged bracts on 4 different axes; first 5 

bracts short, membranous, greenish stramineous, irregularly 

truncate, lobed, or dentate at the summit, strongly severalnerved, bracts 1-111 facing the rachis of the inflorescence and 

smaller than bracts IV and V; bract VI separated from bracts 

I-V by a curved, glabrous internode; bract VI large, indurate, 

slightly saccate-based (gymnostegial flap), obscurely manynerved, bearing a long terminal awn, this straight in the lower 

portion, strongly coiled in the upper part and at maturity 

becoming entangled with the awns of other pseudospikelets, 

all pseudospikelets in the inflorescence frequently shed as a 

unit; bracts VII and VIII similar, appearing to be placed 

opposite bract VI, sometimes fused at the base, triangularlanceolate, indurate, their summits spreading away from each 

other; bract IX usually present only as a minute flange of tissue 

above and opposite the attachment of bracts VII and VIII; 

bracts X-XI1 subequal, coriaceous, lanceolate, unawned, 

strongly nerved, forming a trimerous whorl around the floret, 

but with overlapping margins. Andrecium: Stamens 6, exserted 

from the pseudospikelet but not pendent, the filaments attached 

to the anthers a short distance above their bases, the filaments 

free to fused into a stamen tube; ovary glabrous. Gynecium: 

Stigmas 3, hispid; fruit a linear-lanceolate caryopsis, the hilum 

linear (or broadening in center of caryopsis), extending only 

about 2/3 of the length of the grain; embryo small, basal, lacking 

an epiblast. 

Key to the Species of Streptochaeta 

1. Pseudospikelets (42)70-100 per inflorescence; leaf blades large, 17-30 cm long, 

5-9.5 cm wide [moist to more commonly wet forests, Mexico to Panama; Venezuela 

(rare); Pacific Ecuador; Amazonian Peru (rare)] .......... 1. S. sodiroana 

1. Pseudospikelets 5-19 per inflorescence; leaf blades various, in the common species 

usually less than 17 cm long and 5 cm wide. 

2. Leaf blades 5-18 mm wide, hirtellous below; pseudospikelet bracts X-XI1 

12-14.5 mm long [rare endemic of Espirito Santo, Brazil] . 3. S. angustifolia 

2. Lcafblades 30-73 mm wide, glabrous or rarely hirtellous below; pseudospikelet 

bracts X-XI1 16-23(30) mm long. ............... .2. S. spicata 

3. Pseudospikelets 5-1 1 per inflorescence; leaf blades 11-16(20) cm long, 

3-5(6) cm wide; widespread; Mexico and Trinidad to Paraguay and Rio 

Grande do Sul, Brazil ............. 2a. S. spicata subsp. spicata 

3. Pseudospikelets 13-19 per inflorescence; leaf blades 19-29 cm long, 

4.8-7.3 cm wide; endemic to Pacific Ecuador. ............... ............. 2b. S. spicata subsp. ecuatoriana, new subspecies 
30 SMITHSONIAN CONTRIBUTIONS TO BOTANY 

1. Streptochaeta sodiroana Hackel 

 FIGURE^ 16, 17 

Streplocheta sodiroam Hackel, 1890:111. [Type: Ecuador. Pichincha: Tan 

Mguel, in silv. trop. flumen Peripa," anno 1883, L. Sodiro 911 [or 9ll?] 

(Holotype, W; isotypes, W (2 sheets), fragment at US.] 

Los Angeles, Molina et al. 17684 (BM, F, MO, NY); between 

Upala and San Antonio de Upala, Pohl and Gabel 13563 (F, 

MO); El Fo/sforo, 3 km N of Upala, Pohl and Gabel 13707 

0; 12.6 km N Of Bijagua by road, Pohl and Pinette 13231 

(F, MO, NY). GUANACASTE: Frontera Norte, anno 1910, 

Brenes sen. 0. HEREDIA: Finca La Selva, 3 km S of Puerto 

Viejo, Hammel 8056 (DUKE), 8429 (DUKE). LIMoN: Rio 

aI, 10305 (F, MO); Finca neobroma, Rio Hondo, near Rio, 

cimarrones viejo, caldordn 2108 (US); Bandeco Farm #3, 

km E of ~1 carmen, bnt 2435 (F, MO); base of ceno 

Tortugero, Pohi and Lucas 13046 0; Laguna Alova [sic, for 

Jalaba], 55 km of Main, pohl and ,rucas 13048 0; La 

Columbiana farm, Standley 36809 (US); Collines de Sikubeta, 

Talamanca, Tonduz 9201 (BR, US). PUNTARENAS: hills above 

DESCRIPT1oN*--plants cespitose in Of a few culms, Camam (Ria Sand Box), Bribri, 9O37'N, 82049'W, Burger et 

mature culms sometimes becoming decumbent and rooting at 

the lower nodes. Culms 50-100 cm tall, unbranched above the 

base, frequently stout, 3-9 mm in diameter, glabrous, with a 

small cen@al lumen; lower nodes exposed, short-hispid. 

Leaves: Leaf sheaths glabrous below, the margins fringed near 

Summit with papillose Cilia; sheath auricles absent Or 

uncommonly Present and UP to 5 mm long; lateral appendages 

Hondo, near 

inconspicuous, rarely to 3 mm long, if present fringcd with 

oral setae 1-2.5 mm long; pseudopetiole 4-lO(13) mm long, 

terminating in a stout pulvinus; pulvinus dark, turgid, covered 

with fine appressed hairs; expanded portion of blade oval to 

less commonly lanceolate, 17-30 cm long, 5-9.5 cm wide, 

glabrous or with the margins fringed with a few cilia at the 

base; secondary lateral veins and transverse veinlets conspicuous below, 1" nerves 6-8 on each side of the midrib, 3" lateral 

veins spaced 0.6-0.9 mm apart; well-developed blades 3-6 per 

culm. Inflorescence 17-27 cm long, 0.9-1.3 cm wide, erect at 

first but becoming pendent with age, its base included in the 

uppermost bladeless sheath or exserted on a peduncle up to 

20 cm long; rachis finely papillose to appressed-pubescent, 

with a conspicuous tuft of cilia up to 4 mm long on the pedicel 

of each pseudospikelet. Pseudospikelets (42)70-100, crowded; 

bracts I-V 2-4.5 mm long; body of bract VI 12-18 mm long, 

9-13-nervcd, the terminal awn 4-9 cm long, scabrous; bracts 

VII-VIII 8-12 mm long; bracts X-XII10-17 mm long; anthers 

yellow, -5 mm long, the filaments apparently not fused; 

caryopsis 9-12 mm long, 1.5-2 mm wide, the hilum a narrow 

groove in the lower third of the grain, terminating in a broad, 

shallow depression in the central third; embryo 1-1.2 mm long. 

DIsTRIBUTION.--OcCurring from sea level to 250 meters 

(occasionally to 830 meters) in the shaded understory of moist 

to more commonly wet lowland rainforests of Central America 

(Caribbean slope from Chiapas, Mexico, and southern Belize 

south to the canal area of Panama; Pacific slope from near 

Quepos, Costa Rica, south to Darien, Panama), Venezuela 

(Caribbean slope south of Lake Maracaibo), Pacific slope of 

Ecuador (common); Amazonian Peru (rare); not known from 

Colombia (Figure 18). At La Selva, Costa Rica, it is most often 

found at the base of slopes near small sucams. 

ADDITIONAL SPECIMENS SEEN.-BELIZE. Tolcdo, Peck 652 

(K, NY); Tcmash River, Schipp S-961 (US). 

COSTA RICA. ALAJUELA: 1 mi (1.6 km) s Of RiO Penas 

Blancas bridge of CR-142, Hammel et al. 14052 (MO); 4 km 

W of Muclle San Carlos, lO"28' N, 84"30'W, Liesner 14111 

(MO); 2 km N of Santa Rosa, 10"38'N, 84"31'W, Liesner et 

al. 1501 7 (MO, WIS); 1 km W of Jabillos, 10°23'N, 84"33'W, 

Liesner et al. 15162 (MO, WIS); Llanura de San Carlos, near 

.. , 

Palmar Norte, trail to Buenos Aires, Allen 5913 (BM, F, US), 

Croat 35131 (MO), Schubert 1161 (US); 1 km SE of Rio Claro 

along NE side of Carretera Interamericana, 8"39'N, 83"04'W, 

Burger and Matta 4818 (F, NY); 5 km W of Rincon de Osa, 

Burger and Liesner 7214 (F, MO, NY); Finca El Eden, km 

183, Route 2, near Santa Marta, Gomez 22950 (MO); Rincon 

airstrip, Kennedy 1929 (MO); 2 miles (3.2 km) W of Golfito, 

Lathrop 5581 (S, US); Osa forest camp, Lathrop 5585 (US); 

Rincon de Osa, Liesner 1783 (MO), Pohl and Davidse 10749 

0; Sirena, 8"29", 83"36W, Liesner 2941 (MO); 2 km S of 

Hatillo, 9 Oct 1968, Pohl and Davidse (F); 5 km W of Palmar 

Norte on road to Puerto Cortez, Pohl and Davidse 11584 (F, 

K); 3 km NE of Quepos, Pohl and Davidse 11691 0; valley 

of Rio Terraba, S of crossing of Rio Ceibo and Carretera 

Interamericana, Pohl and Davidse 11 773 (F); between Golfo 

Dulce and Rio Terraba, Skutch 5291 (F, US); -10 km S of 

Palmar Sur on the Carretera Interamericana, Finca 18, 

Soderstrom and Calderon 1205 (US, WIS); Playa Blanca, 

Golfo Dulce, Valerio 425 (BR, F). 

ECUADOR. Without locality, Lehmann 4400 (US fragment 

ex K). ESMERALDAS: km 170-175, via Santo DomingoQuininde, Acosta-Solis 13644 (F); Rosa Zarate, Quininde, 

Asplund 16302 (B, G, NY, S); E of Rio Blanco and S of 

Quininde, Fagerlind and Wibom 2553 (S); via EsmeraldasTanaty-Cuchilla de Timbre, Jaramillo 57 (AAU, QCA); Rio 

Cayapas, Kvist s.n. (AAU); Coronel C. Concha, -30 km S of 

Esmeraldas, Maas et a]. 2925 (K, MO). LOS RiOS: Rio Palenque 

Biological Station, km 56 highway Quevedo-Santo Domingo, 

Croat 38964 (MO), Dodson 5021 (US), Gentry 9866 (MO), 

bjtnant and Molau s.n., F1. Ecuador 15752 (AAU); Hacienda 

Ana Maria, Canton Vinces, Mexia 6648 (BM, US); Hacienda 

Monica, 12 km E of San Carlos, Sparre 19388 (S). PICHINCHA: 

20 km W of Santo Domingo de 10s Colorados, Cazalet and 

Pennington 5109 (NY, US); 37 km S of Santo Domingo de 10s 

Colorados, Pennington 49 S.D. (K, NY); Rancho Brahman, 

-10 km NW of Santo Domingo do 10s Colorados on road to 

Esmeraldas, Sparre 15208 (S). 

GUATEMALA. IZABAL: hs Amates, Deam 97 (F, MO, NY, 

W). PEEN: between Finca Yalpamech along Rii San Diego 

and San Diego on Rio Cancun, Steyermark 45355 (F); between 
NUMBER 68 31 

FIGURE 16.-Sirepfochaefa sodiroana: (I, habit, showing pseudospikelets disarticulating from rachis (x 0.29); 

b, junction of leaf shealh wilh blade, showing prominent pulvinus (x 1.42); c, portion of rachis (x 2.29); d, 

pseudospikelet (X 2.29). (a,c,d based on Schubert 1161, Costa Rica (US), b based on Siandley 54180, Honduras 

(US). Illustration by Gesina B. Threlkeld. 
32 SMITHSONIAN CONTRIBUTIONS TO BOTANY 

h 

0 

9 

FIGURE 17.-S~repfochuefa sodiroanu, showing detail of the pseudospikelet: a,b, two views of the complex of 

bracts I-V from the base of the pseudospikelet (X 5.75); c-g, bracts I-V (x 5.75); h,i, two views of a 

pseudospikelet (bracts I-V removed) (X 2.88); j, bract VI, showing gymnostegiurn near base (x 2.88); k, bracts 

VII-VIII; 1-n, bracts X-XII, which envelop the flower (x 2.88); 0, flower in early stage of anthesis, showing six 

stamens and gynecium wilh three stigmas (X 2.88); p, pistil surrounded by delicate stamina1 tube, late stage of 

anthesis (X 2.88); q, caryopsis, ventral face showing hilum terminating in a broad, central depression (X 2.40); 

r, caryopsis, dorsal face showing persistent beak and small, basal embryo (x 2.40). (a, b. h-j, 1-n, q, r based on 

Schuberf 1161, Costa Rica (US); c-g, k, 0, p based on Sfandley 54180, Honduras (US).) Illustration by Gesina 

B. Threlkeld. 
NUMBER 68 33 

Finca Yalpamech and Chinaja, Steyermark 45425 (F, K). NICARAGUA. ZELAYA: region Of Braggman’s Bluff, EnglesHONDURAS. ATLANTIDA: Lancetilla Botanical Garden, S of 

Tela; rainforest on way to Tela water supply dam, Pohl and 

Gabel 13813 (F, ISC), Sfandley 52876 (F, US), 53139 (F, 

US), 54180 (F, US), 55416 (F, US); Puerto Sierra, Lippmann’s 

plantation, Rio Esperanza, Wilson 548 (NY). 

ing 184-8 (F); Cerro Waylawas, 13”38-39’N, 84’48-49113 

Pipoly 4193 (MO); montanas de Esquipulas y Aleman, drenaje 

Rio Aleman, Shank and Molina 4829 0; drenajes de 10s Rios 

Punta Gorda, Alemain, y Zapote, Shank and Molina 4974 0; 

trail Cerro Saslaya to San Jose del Hormiguero, between Cano 

PICUKE 18.-Distribution of Slreptochaeta sodiroana. 
34 SMITHSONIANCONTRIBUTIONS TO BOTANY 

Majagua and Cano Sucio, approximately 13"45'N, 85"00'W, 

Stevens 6852 (ISC); along Rio Waspuk, -1 km upstream from 

confluence of Rio Pis Pis, 14"15'N, 84"36W, Stevens 13084 

(MO); -1.5 km NE of La Esperanza de Las Quebradas, 

13"38'N, 85"02'W, Stevens 19341 (MO). 

PANAMA. BOCAS DEL TORO: Filo Almirante, trail to Risco 

Abajo, 3 km SW of Almirante, Nee and Hansen 14104 (F, 

MO, WIS). CANAL AREA: Barro Colorado Island, Aviles 23-B 

(MO), Busey and Croat 246 (MO), Calderon 2096 (US), Croat 

(F, MO), 12930 (MO), 13226 (MO), Foster 1764 0, 

Judziewicz 4435 (MO, WIS), Kenoyer 103 (US), Maron et al. 

6824 (NY, US), Shattuck 755 (F, MO), Standley 31374 (US), 

4I084 (US); Juan Mina, Salvador Hill, Bartlett and Lasser 

16790 (MO); Pipeline Road, 9"15'N, 79"45W, Hamilton et 

al. 3242 (MO); headwaters of Rio Chinilla, above Nuevo Leon

Mamn 6896 (US). CHIRIQUI: road from Puerto Armuelles to 

San Bartolo Limite, 7 km W of Puerto Armuelles, Croat 

35066 (MO); Rabo de Puerco, 8 km W of Puerto Armuelles, 

Liesner 26 (MO); Cerro de la Plata, near San Felix, Pittier 

5164 (US). cocLE: Cerro Moreno between Molejon and 

Coclecito, 8"46'44"N, 80"31'54"W, Davidse and Hamilton 

23707 (MO); road fom La Pintada to Coclecito, 8"45'N, 

8Oo30'W, Hamilton and Davidse 2871 (MO). COLON: Rio 

Escandaloso, near abandoned manganese mine, Hamme12666 

(MO). DARIEN: Rio Aruza, Bristan 1364 (US?), upper Rio 

Tuquesa, le Clezio 45 (MO); Rioo San JoeC, Duke and Bristan 

415 (MO); Cerro Sap, Hammel 1217 (MO); 2-3 mi (34.8 

km) SE of Pijibasal on Rio Paraseneco, -9-10 mi (14.5-16 

km) S of El Real, Hartman 12056 (MO); Rio Pirre, trail up 

river from house of Bartolo, Kennedy 2900 (MO, US). 

PANAMA: 3 km from Caiiitas towards Bayano Dam, Calderon 

and Dressler 2153 (US); Serrania de Maje, trail between 

headwaters Rio Ipeti Grande and Charco Rico, So53'N, 

78"32'W, Churchill and de Nevers 4408 (MO); 4-5 hours 

walk upriver from Torti Arriba, Folsom et af. 6836 (MO); 9 

km N of Margarita on road to Madrono, Hamme16036 (MO); 

Serranias de Maje, ridges S of Choc6ovillage of Ipeti, So47'N, 

78"27'W, Knapp and Sytsma 2366 (MO); ChimAn, Lewis et 

al. 3252 (MO). 

PERU. LORETO: Prov. Nauta, Rio Samiria, puesto vigilancia 

Santa Elena, 115 m, Encarnacion 25321 (USM, not seen; 

fragment and photocopy, WIS). 

VENEZUELA. MREI DA: El Vigia-Panamericana-Cniio Amarillo, 100-200 m, selva pluvial, abundante en cierta zona del 

bosque, Bernardi 1891 (NY, US). 

VOUCHER SPECIMENS FOR ANATOMICAL STUDIES.- costa 

Rica: Calderon 2108 (US) (starch grains, embryos), Liesner, 

Judziewicz, and Garcia 15162 (MO) (starch grains, embryos), 

Soderstrom and Calderon 1205 (US) (leaves, starch grains, 

embryos). Ecuador: Mexia 6648 (US) (starch grains, embryos). 

Panama: Calderon 2096 (US) (starch grains, embryos). 

DIscUssIoN.-Srreptochaeta sodiroana flowers principally 

during the dry season, from December through March. Lars 

P. Kvist (AAU, pers. comm.) indicates that both the Cayapas 

5313 (F, MO), 6325 (MO), 7092 (F, MO), 7380-A (MO), 8816 

and Colorado tribes of Pacific Ecuador use the immature 

inflorescences to remove facial hair, a process he has witnessed 

several times. 

2a. Streptochaeta spicata subsp. spicata 

Schrader ex Nees von Esenbeck 

FIGURE 19,20 

Sfrepfochefu spicufu Schrader ex Nees von Esenbeck, 1829537. [Type: 

Brazil. Bahia: "Im urwald an der Estrada de Minas [illegible] Capitain 

Fdisbeno" [Fazenda of Felisberto Caldeira Brant, Marques de Barbacena, 

near Ilheus], anno 1816, Prince Muximilkn A.F. de Neuwied s.n. [or 120?] 

(Holotype, B, fragment US; isotype, BR).] 

fepideilem luncifoliwn Trinius, 1830:93. [Type: Brazil, no collector or exact 

locality given.] 

DESCRIP~ON.-P~~~~~ cespitose in clumps of a few culms, 

sometimes becoming decumbent and rooting at the nodes. 

Culms 35-105 cm tall, 2-4 mm in diameter, unbranched above 

the base or rather frequently rebranched 1-3 times in scorpioid 

fashion, successive branches borne on one side of the plant, 

each branch bearing a terminal inflorescence; lower nodes 

exposed, glabrous to finely appressed-hispid. Leaves when 

fully developed (3)5-7(10) per culm, the leaf sheaths 4-6(7) 

cm long, glabrous except sometimes puberulent on the back 

and ciliate on the margins near the summit; sheath auricles 

absent to frequently prominent, up to 9 mm long; lateral 

appendages usually inconspicuous, up to 2 mm long, fringed 

with oral setae 1-2.5 mm long; pseudopetiole 2-7 mm long, 

the terminal pulvinus dark, turgid, pubescent; expanded portion 

of blades elliptic-lanceolate, less commonly oval or narrowly 

lanceolate, 11-16(20) cm long, 3-5(6) cm wide, shiny, dark 

green, and glabrous above, glabrous or (rarely) hirtellous 

below, especially near the apex, the margins smooth to 

scabrous, the 1' lateral veins 4-6 on each side of the midrib, 

the 3" lateral veins spaced 0.45-0.65 mm apart, the transverse 

veinlets inconspicuous on both surfaces. Inflorescence 9-16 

cm long, included in uppermost bladeless sheath or exserted 

on a peduncle up to 16 cm long; rachis pubescent with 

rusty-colored, curling cilia, especially on the pseudospikelet 

pedicels near the summit. Pseudospikelets 5-1 1, separated by 

internodes 10-23 mm long, borne on pedicels 0.9-1.3 mm 

long; bracts I-V up to 3-6 mm long; body of bract VI 17-28 

mm long, 7-13-nerved, the terminal awn 3-9 cm long, glabrous 

to slightly scabrous; bracts VII-VIII 11-15 mm long; bracts 

X-XII14-23(30) mm long; stamens in 2 groups of 3 each, the 

filaments of each group apparently fused for a short distance 

at the base; caryopsis 12-16 mm long, 1.5-2 mm wide, 

lanceolate, tapering to apex, the ovary persistent at the summit 

as a small, glabrous beak, the hilum a narrow groove extending 

through the lower two-thirds of the grain; embryo 1-1.2 mm 

long. 

DISTRIBUTION.-Moist or wet forests below 500 meters 

(occasionally to 1000 meters), often in old treefall gaps or on 

steep rocky slopes, from Veracruz, Mexico, and Trinidad to 
NUMBER 68 35 

FIGURE 19.Streptochaeia spicata subsp. spicaia: a, habit, showing disarticulated pseudospikelets pendent by 

awns from the apex of the rachis (note lateral branch of culm terminating in a second inflorescence) (x 0.26); 

b, base of plant showing stout sympodial rhizomes (x 0.52); c, summit of leaf sheath and base of blade showing 

prominent sheath auricle tipped oral setae (X 1.57); d, view of opposite side of summit of leaf sheath and base 

of blade showing smaller sheath auricle and turgid pulvinus (X 1.57). (a based on Bailey and BaiIey 723, Brazil 

(US); b, d based on Chase 11011, Brazil (US); c based on Garnier4459, Nicaragua (US).) Illustration by Cesina 

B. Threlkeld. 
36 SMITHSONIAN CONTRIBUTIONS TO BOTANY 

the Pacific slope of Ecuador (rare), Amazonian Peru (rare), BOLIVIA. SANTA CRUZ: Estancia La Dolorida, 500 m, 

Paraguay, and Rio Grande do Sul, Brazil; scattered throughout 16"15'S, 62"15W, Killeen 1968 (ISC). 

its range; most common in Atlantic and southern Brazil (Figure ADDITIONAL SPECIMENS SEEN.-BRAZIL. Without locality, 

21). Riedel s.n. (G, P). BAHIA: km 5, rodovia Lages-Ubaitaba, 

P 

~ f 

4 d 

0 

FIGURE 20.Sfrepfochefa spicala subsp. spicata, showing details of pseudospikelet: a, portion of rachis 

showing pseudospikelet pedicel covered with hooked hairs (x 2.35); b, pseudospikelet, showing long awn on 

bract VI (X 2.35); c-g, series of bracts I-V at the base of a pseudospikelet, showing their variable venation and 

shape (X 2.35); h, views of base of bract VI, showing the gymnostegial area and the internode between bract V 

and bract VI (X 2.35); i, bracts VII and VIII (x 2.35); j-l, bracts X-XI1 (x 2.35); m, andrecium showing short, 

elongating stamen tube (x 2.35); n, gynecium (x 2.35); o, caryopsis, ventral view, showing linear hilum (x 

2.35); p, caryopsis, dorsal view showing persistent style and small, basal, embryo (x 2.35). (All based on Bailey 

and Bailey 723, Brazil (US).) Illustration by Gesina B. Threlkeld. 
NUMBER 68 37 

approximately 14'1 8'33"S, 39' 19'30"W, Calderon 2041 (US); 

km 5 camino hacia Santa Cruz Cabralia, approximately 

16'15'06"S, 39'00'18'W, Calderon 2046 (US); Ferradas, 

Fazenda Aberta Grande, 14 km SW of Itabuna, approximately 

14'51'S,39"20'W, Calderon and Pinheiro 2162 (US); Reserva 

Biologica Pau Brasil, 16 km W of Porto Seguro, approximately 

16'23'S, 39'11W, Calderon and Pinheiro 2193 (US); 6 km 

E of Ubaira City, Rio JequiriCA, approximately 13'163, 

39'37'W, Calderon and Pinheiro 2246 (US); rodovia BA-265, 

trecho Caatiba-Barra do Choca, 6 km W de Caatiba, Mori and 

dos Santos 11577 (MO, NY, US); CEPEC, Municipio Ilheus, 

dos Santos 3419 (RB); Fazenda Uruguayana, 8 km S of Santa 

I I I 1000 km I I i 

Cruz de Vitoria, Soderstrom et al. 2118 (US); Reserva 

Gregorio Bondar, experimental station of CEPEC, Municipio 

Belmonte, Soderstrom et al. 2139 (US). CEARA: Serra de 

Baturite, Ule 8991 (G, K). ESPIRITO SANTO: Canto Grande, 

Reserva Florestal de Linhares, 19'24'S, 4Oo04W, Soderstrom 

and Sucre 1881 (US), 1896 (US), Zulouga et al. 2437 (US); 

Flecheira, Municipio Atilio Vivacqua, Soderstrom and Sucre 

1911 (US); road from Cachoeiro de Itapemirin to Itabira, 

20'51' S, 41"05W, Soderstrom and Sucre 1963 (RB, US). 

MAT0 GROSS0 DO SUL: vicinity of Dourados, Chase 11011 (F, 

MO, RB, US), Swallen 9403 (US). PARA: range of hills -20 

km W of Rendencao, near Corrego Sila Joga and Troncamento 

FIGURE 21.-Distribution of Sfrepfochaeta spicata subsp. spicata (dots) and S. s. subsp. ecuutoriana (asterisks). 

Inset shows distribution of Slreptochaeta angustijolia (triangle) and Anomochloa marantoidea (circled star). 
38 SMITHSONIAFV CONTRIBUTIONS TO BOTANY 

Santa Teresa, approximately 8"03'S, 50" IO'W, Plowrnan et 

al. 8646 (MO, NY, US). PARANA: Rio Ivai, Municipio Terra 

BOa, Hatschbach 15727 (F, MO); 7 km E of Londrina, Swallen 

8743 (US); Rio Vermelho, 18 km NE de Bela Vista, Tessmann 

3830 (us). RIO DE JANEIRO: Mun. Macaee, Lagoa Comprida, 

Araujo 4984 (K); Corcovado range, Bailey and Bailey 723 

(US), Glaziou 13327 (BM, K, P, W), Hoehne 17226 (NY, 

US); Camino dos Macacos, Jardim Botahica to Alto Boa Vista, 

Chase 8430 (F, MO, NY, US, W); Rio Comprido, Rio de 

Janeiro, Glaziou 5438 (US fragment), 5439 (P, W), 5449 (S), 

17925 (K, W); Palmeiras, Hemmendorff 303 (S); Parque 

Estadual de Desengano, Fazenda Agulha do Imbe, 21'56'S, 

41'52'W, Plowman and de Lima 12929 (F); Morro Novo 

Mundo, Soderstrom and Calderon 1861 (B, US); Reserva de 

Tinguai, Municipio Nova Iguacu, Soderstrom 2632 (US). NO 

GRANDE DO SUL: estrada BR-101, Colonia Sao Pedro, 

Municipio Torres, Valls 1095 (US); Tres Cachociras, 6 km 

from ocean, 29'27'S, 49'56'W, Soderstrom et al. 1989 (US). 

RONo~NIA: Igara-pe, Miolo, affl. do Gy-Parana, Kuhlmann 

1834 (US). RORAIMA: Coohia Fernando Costa, iio Mucajai, 

Black and Magalha'es 51-12891 (K, P, US). SANTA CATARINA: 

Blumenau, anno 1887, Miiller s.n. (MO, RB), Schwacke 5749 

(RB), Ule 980 (P); Municipio Icra, km 376 da BR-101, no 

trecho de Tubaraio a Criciuma, Valls et al. 2736 (US). saao

PAULO: 1 km W Rio Sao Mateus, Municipio ParaguaCU 

Paulista, 22'32'S, 5Oo48W, Clayton 4581 (K); beira de mata 

de Planalto, Municipio Adamantina, Taroda s.n. (F). 

COLOMBIA. META: RIo GUejar, -10 km below junction with 

RIo Zanza, N end of Cordillera Macarena, Smith and Idrobo 

1530 (US). 

COSTA RICA. GUANACASTE: Hacienda Guachipelin, ParqUe 

Nacional Volcan Rincon de la Vieja, Pohl and Davidse 11672 

(K); 1 km W of hcadquartcrs, Santa Rosa National Park, Pohl 

and Erickson 12631 (ISC), Janzen 12213 (MO), Judziewicz 

4279 (F, WIS). 

ECUADOR. LOS Rios: Hacienda Clementina on Rio Pita, 

Asplund 5562 (S, US). 

Montana del Mico, trail between Dartmouth and Morales, 

towards Lago Izabal, Steyermark 39029 (F, US); N slope of 

ridge N of Quirigua, Weatherwax 105 (US). PETEBN: Ceiba

Molina 15864 (F, NY). 

HONDURAS. OLANcHO: Rio Talgua, near the Escuela Granja 

Demonstrativa de Catacamas, Molina 8328 (US); along Hwy. 

3, 12 km SW of Dulce Nombre de Culmi, Pohl and Davidse 

12447 (ISC). 

MEXICO. CHIAPAS: near junction of Rio Pcrhs and Rio Jatate 

at San Quintin, near Laguna Miramar, Sohns 1725 (US). 

OAXACA: Cerro de Nacimiento, E of Cosolapa, 17-20 km NE 

of Campo Experimental de Hule, Sanfos 2438 (US). VERACRUZ: Atoyac, Dull 125a (B); Cordova, Finck s.n., Feb 1893 

(K, NY); 7 km E of Sarabia, San Juan Guichicobi, Vazquez 

1399 (BM, MO, WIS); Ejido de Manzanares, 1-4 km NW of 

Campo Experimental de Hule, Santos 2301 (US). 

NICARAGUA. Without locality, Garnier 4459 (US). ZELAYA: 

GUATEMALA. IZABAL: El Estor, Confreras 11538-A (LL); 

between Waspam and Ulwas, Pohl and Davidse 12296 (ISC); 

Miguel Bikan, -52 km SE of Waspam, Pohl and Davidse 

12311 (F, ISC); crossing of Rio Lekus on road to Puerto 

Cabezas, Pohl and Davidse 12319 (F, ISC). 

PANAMA. CANAL AREA: Barro Colorado Island, Calderon 

2095 (US), Caldero'n and Dressler 2145 (US), Croat 4243 (F, 

MO, NY), 11832 (MO), Foster 2038 (F), 2316 0, Knight 

s.n. (WIS), Shattuck 724 (F, MO); hills N of Frijoles, Standley 

27489 (BM, MO, US). CHIRIQIf: Cerro de la Plata, near San 

Felix, Pittier 5164'/z (US). DARIEN: trail between Pinogana 

and Yavisa, Allen 245 (MO, US); Rio Chico, 1 hour by boat 

from Yaviza at junction of Rio Chucunaque (MO, US), Duke 

and Bristan 451 (MO); trail from Pucuro to Cerro Mali, 

Quebrada Pobre to La Laguna, Gentry and Mori 13549 (MO, 

NY); Rio Chico, 10 km upstream from Narazeth, 8'20'N, 

77'25'W, flahn 113 (MO); 0.5-2.5 mi (0.84 km) NE of 

Manene, Hartman 121 73 (MO); trail from Canglon-Yaviza 

road to Rio Chucunaque, 7.7 mi (12 km) E of Canglon, 8'20'N, 

77'50'W, Knapp and Mallet 3962 (MO); junction Rio Canglon 

and Rio Chucunaque, 15 km N of Yaviza, Mori 374 (WIS). 

PANAAA: -2 mi (3 km) up Rio La Maestra, Kennedy 1186 

(US); Chiman, 3-4 mi (4.8-6.4 km) up Rio Pasiga, Kennedy 

1209 (MO, US), Lewis et al. 3237 (MO); edge of mangrove 

swamp S of Ft. Kobbe and Ft. Howard, E of Rio Venado, 

8'54'N, 79'35'W, Knapp 1893 (MO). 

PARAGUAY. Plaine de Pirayu-bi, Balansa 179-A (G, also 

fragment US); Cordillera de Peribebuy, fhret de Naranjo, 

Balansa 4373 (BM, G, K, P), Hassler 131 7 (G); Puerto Bertoni, 

Bertoni 5825 (W); Prov. Amambay, Parque Nacional Cerro 

Coro, Soloman et al. 6869 (MO). 

PERU. AMAZONAS: Prov. Bagua, Quebrada Mirana (above 

km 277 of Maranon Road), valley of Rio Marano6n above 

Cascadas de Mayasi, Wurdack 1895 (F, NY, US). 

TRINIDAD. Caparo forests, Broadway 4929 (US). 

VENEZUELA. ANZOATEGUI: Cerro La Danta, bordering 

tributary of Rio Leon, NE of Bergantin, Steyermark 61087 (F, 

US). APURE: Selva de Cutufi, 7'09-1 I'N, 7I056-58W, Davidse 

and Gonzalez 21723 (MO, NY, US). BARINAS: SW of 

Barinitas, Bunting 2265 (MO). ZULIA: cuenca del Embalse 

Burro Negro (Pueblo Viejo), sector between Quiros-El 

Pensado and the foot of Cerro Socopo, -10 km E of 

Churuguarita, Bunting 9448 (MO); Cerro Las Manantiales, E 

of Rio Guasare, 12 km W of Corpozulia Campamento 

Carichuano, 1 l0O1'N, 72'20'W, Steyermark et al. 123241 

(MO, NY, US). 

Calderon 2046 (US) (leaves), Chase 8430 (US) (starch grains, 

embryos), Soderstrom and Calderon 1861 (US) (spikelet), 

Soderstrom and Sucre 1896 (US) (starch grains, embryos). 

Panama: Allen 245 (MO) (embryos), Calderon and Dressler 

2145 (US) (culm, leaves). 

DrsCUSSION.-~af blade number, size, and shape are 

variable in Streptochaeta spicata. While most populations 

have lanceolate blades, those from near Rio de Janeiro, Brazil 

and near Lake Maracaibo in Venezuela have ovate blades, 

VOUCHER SPECIMENS FOR ANATOMICAL STUDIES.- Brazil: 
NUMBER 68 39 

which are, however, no longer than those of most populations 

of the species. Bahian populations of S. spicata also exhibit 

vegetative variability: some individuals have only 3 fully 

developed ovate blades per culm, while others possess up to 

10 narrowly lanceolate blades, and some narrow-leaved 

populations (Mori and Santos 11577; Soderstrom et al. 2118) 

have abaxial surfaces bearing an indumentum of scattered 

pilose hairs with distinctive swollen bases, a feature that is 

otherwise well developed only in S. angustifalia (Figure 24c,6). 

However, these unusual specimens of S. spicata have overall 

blade surface areas that are much closer to that of characteristic 

specimens of S. spicata subsp. spicata (Figure 22) and their 

pseudospikelets are not as small as those of S. angustifolia. 

In Central America S. spicata subsp. spicata exhibits a 

flowering peak during November and December, and possibly 

also July and August. Nearly all Atlantic Brazil collections 

have been made during the period from February through April. 

2b. Streptochaeta spicata subsp. ecuatoriana, 

new subspecies 

TYPE SPECIMEN.-Ecuador, Los Rios: Jauneche forest, 

Canton Vinces, km 70 on road from Quevedo to Palenque, N 

of Mocachi on Estero Penafiel, 100 m, 23 Mar 1980, C.H. 

Dodson and A.H. Gentry 9832 (Holotype, MO). 

DESCRIPTION.-Differt a Streptochaeta spicata subspecies 

spicata laminae longiore (19-29 cm) latioreque (4.8-7.3 cm), 

inflorescentia longiore (18-30 cm), et spiculis 13-19. 

Plants apparently cespitose. Culms 70-100 cm tall, apparently unbranched above the base, 3-5 mm in diameter, the 

lower nodes exposed. Leaves 4-6 per culm, the leaf sheaths 

glabrous except along margins near the summit; sheath auricles 

inconspicuous, to 1.5 mm long; lateral appendages inconspicuous, to 1 mm long; oral setac 1-2 mm long; pseudopetiole 

2-10 mm long, the expanded portion of the blade 19-29 cm 

long, 4.8-7.3 cm wide, glabrous except occasionally for a few 

scattered hairs on the lower surface near the margins, the 3" 

lateral veins and transverse veinlets not particularly conspicuous on eithcr surface. Inflorescence 18-30 cm long, -0.8 cm 

wide, exsertcd on a peduncle 1-14 cm long; rachis pubescent. 

Pseudospikelets 13-19, not crowded; bracts I-V up to 4-7 

mm long; body of bract VI 20-25 mm long, 12-nerved, the 

awn -6 cm long; bracts VII-VIII 12-15 mm long; bracts 

X-XI1 17-22 mm long; stamens not seen; immature caryopsis 

8 mm long, linear-lanceolate. 

DISTRIBUTION.-Endemic to moist, lowland forests on the 

Pacific slope of Ecuador (Figure 21). 

PARATYPES.-ECUADOR. GUAYAS: between Las Americas 

and Palme, 28 Scp 1952, Fagerlind and Wibom 374 (MO, S); 

Rio Daulc bclow Pichincha, Hacienda Santa Barbarita, 18-26 

Apr 1959, Hurling 4798 (S). Los RIOS: Jauneche forest 

[topotypes], 15 Aug 1978, Dodson et al. 7067 (MO, US), 1 

Apr 1980, Dodson and Gentry 10126 (MO), 20 Feb 1982, 

Dodson and Gentry 12706 (MO), 14 Jan 1981, Gentry el al. 

30709 (MO). MAIVABI: El Recreo, 22 Aug 1893, Eggers 14863 

CF, M, US). 

dor: Dodson et al. 7067 (US) (leaves). 

COMMENTS.-FOW of the five populations of S. spicata 

known from Ecuador are robust plants with blades twice as 

large (as measured in surface area) and with twice as many 

pseudospikelets than is average for subspecies spicata (Figure 

22). We have chosen to recognize these plants as the new 

subspecies S. spicata subsp. ecuatoriana. The single specimen 

of subspecies ecuatoriana examined anatomically had extremely long bicellular microhairs on the leaf blades. 

The herbaceous bamboo flora of western Ecuador is 

impoverished by the apparent absence of common olyroid 

genera such as Pariana, Arberella, and Piresia, but non-olyroid 

tribes are well represented by Pharus (5 species, including a 

new endemic) and Streptochaeta. 

VOUCHER SPECIMENS FOR ANATOMICAL STUDIES.- ECU3. Streptochaeta angustifolia Soderstrom 

Streptochaefa angustifoliu Soderstrom, 1981a:30. [Type: Brazil. Espirito 

Santo: Municipio Cachoeiro de Itapemirim. 10 km from Cachoeiro toward 

Alegre, 2Oo47'S, 41'09W, low forest dominated by Rutaceae with open 

understory, soil sandy clay, about 35 plants seen growing in several 

rhizomatous clumps, in fruit, 26 Apr 1972, TR. Soderstrom and D. Sucre 

1969 (Holotype, RB; isotypes, CEPEC, F, INPA, K, LE, MO, NY, P, US).] 

DESCRIPTION.-P~~~~S cespitose from a knotty, shortrhizomatous base, but also spreading by decumbent and rooting 

culms to form large clones. Culms 40-70 cm tall, hollow, 

glabrous except pubescent in a line below the nodes; nodes 

finely appressed-pubescent; unbranched or sparingly branched 

above, 2-2.5 mm in diameter. Leaves 4-8, evenly distributed 

on culms or in some sterile shoots the internodes shortened 

near the summit, forming a crowded fascicle of leaves with 

strongly overlapping sheaths; leaf sheaths glabrous except for 

ciliate margins in upper portion; sheath auricles, lateral 

appendages, and oral setae inconspicuous; pseudopetiole 

poorly differentiated from expanded portion of blade; blades 

narrowly lanceolate, 12-15 cm long, 1.3-1.7(2) cm wide, 

scaberulous on the upper surface, hirtellous or less commonly 

glabrous on the lower, the margins smooth at the base, scabrous 

near the apex; primary nerves 3 or 4 on each side of midrib; 

3" lateral veins spaced about 0.4 mm apart; transverse veinlets 

inconspicuous on both surfaces. Inflorescence 8-1 1 cm long, 

borne on a subglabrous peduncle 10-13 cm long, the rachis 

flocculose. Pseudospikelets 6-9, not crowded, borne on 

ciliate-uncinate pedicels about 0.7 mm long; bracts I-V up to 

3 mm long; bract VI 10-14 mm long, 12-nerved, with an awn 

3-5 cm long, scabrous; bracts VII-VIII 8.5-10.5 mm long, 

8-or 9-nerved; bracts X-XI1 12-14.5 mm long, 12-15-nerved; 

filaments fused, forming a delicate tube surrounding the 

gynecium, the anthers yellow, 5.4 mm long, the free part of the 

filaments above -2 mm long; ovary fusiform, -4 mm long, the 

style to 3 mm long; stigmas -5 mm long. 

DISTRIBUTION.-Known only from a single moist lowland 
40 SMITHSONIANCONTRIBUTIONS TO BOTANY 

forest (-90 meters elevation) in Espirito Santo, Brazil (Figure 

21). 

ADDITIONAL SPECIMENS SEEN.-BRAZIL. BAHIA: Plants 

from type population cultivated at Sucre property, Vargem 

Grande, Jacarepagua, Rio de Janciro, 15 Mar 1986, Judziewicz 

VOUCHER SPECIMENS FOR ANATOMICAL STUDIES.- Brazil: 

Soderstrom and Sucre 1969 (US) (leaves). 

DISCUSSION.-S~~ comments under Streptochueta spicata 

subsp. spicata. As noted by Soderstrom (1981a, fig. 6h) the 

filaments of this species are fused into a delicate stamen tube, 

s.n. (WIS). a feature also present in the herbaceous bamboos Froesiochloa 

20 

18 

16 

14 

12 

10 

8 

6 

4 

3 

* 

** * 

A 

AA 

A 

A 

0 0 

0 00 0 

0: 

00 n 

f 

A 

1 .o 1.5 2.0 2.4 

Leaf Blade Area 

FIGURE 22.-Plot of pseudospikelet number versus leaf-blade size for MO and US collections of Sfrepfochaeta 

spicala subsp. spicata (solid circles); S. s. subsp. ecuaforinna (triangles), and S. angurfifolia (stars). The index 

for leaf-blade size (area) was computed by taking the logarithm of the product of leaf-blade length times width 

(both measured in centimeters). 
NUMBER 68 41 

(Olyreae), Puelia spp. (Puelieae), and Buergersiochloa (Buergersiochloeae), as well as in several genera of woody bamboos 

such as Gigantochloa (Soderstrom, 198 la). 

As is evident to anyone flying from Salvador to Rio de 

Janeiro, the forests of the Brazilian state of Espirito Santo, 

except for a few small reserves, have been destroyed. The 

olyroid herbaceous bamboo Sucrea sampaiana (two collcctions, 1924 and 1929), which grew here, is probably extinct, 

and it is likely that Streptochaeta angustifolia, collected only 

in a tiny remnant forest patch in 1972, is by now also extinct 

in the wild. However, the species has survived for 14 years in 

cultivation near Rio de Janeiro due to the care of Sr. Dimitri 

Sucre, who recently donated a plant from his thriving 

population to the Smithsonian Institution greenhouse in 

Washington, D.C., where it bloomed in August 1986. 

MORPHOLOGY-ANATOMY 

Culm, Leaf Sheath, and Pulvinus 

The culms of all species of Streprochaeta are hollow, with 

the lumen ranging from about l/3 to over of Lhc diamcter 

of the culm. In a culm sectioned for this study (S. sodiroana, 

Soderstrom 1205) a circle of 42 alternating large and small 

vascular bundles, partially embedded in sclerenchyma, was 

noted subjacent to the epidermis and separated from it by a few 

rows of parenchyma. Interior to this ring was a ground tissue 

of parenchyma cells that extended all the way to the central 

lacunae, within which were embcdded numerous scattered 

vascular bundles. The parenchyma cells were largest in the 

region midway between the epidermis and the lacunae, with 

the cells immediately adjacent to the lacunae noticeably smaller 

and with slightly thicker walls. 

The leaf shcaths of Streptochaeta species are solid and 

crescent-shape in cross-scction and do not have membranous, 

winged margins. In acropetal serial sections of S. sodiroana 

and S. spicata subsp. spicata the shape changcs from concave 

to triangular, as the pulvinar area is approached, with the 

adaxial side slightly concave and the corners of the triangle 

rounded (Figure 54. The epidermis has abundant rounded, 

silicified papillae and long, ciliate macrohairs, the latter 

particularly abundant on the adaxial epidermis. The main 

vascular bundles are disposed in a V-shape arc of about 20 

bundles situated closer to the abaxial epidermis than to the 

center of the pulvinus; the peripheral bundles each have an 

irregular sclcrenchymatous cap proceeding to the adaxial 

epidermis. Several arcs of minor vascular bundles are also 

present: an arc of about five tiny bundles is present abaxial to 

the main arc; an irregular arc of about ten small bundles is 

present subjacent to the adaxial epidermis; and there is an 

isolated medium-size vascular bundle present in nearly the 

exact centcr of the pulvinus, bctwccn thc main arc and the 

adaxial arc of small bundles. 

Leaf-blade Anatomy 

TRANSVERSE SECTION (Figure 7a-c).-Outline: blade flat, 

the epidermides straight or with only slight undulations on the 

abaxial surface, with the blade thickest near the vascular 

bundles and thinnest near the bulliform cells. Midrib outline: 

distinctive, projecting both adaxially and abaxially; adaxial 

projection anvil- or keystone-like, slightly narrowed at the base 

and with a broad, flat top and overhanging corners; abaxial 

projection low-domed or low-rectangular. Midrib vasculature: 

complex, with several tiers of vascular bundles; one large 

median bundle always present subjacent to the abaxial 

epidermis, this flanked or not with minor bundles, and one to 

several vascular bundles usually present subjacent to the 

abaxial epidermis. Midrib sclerenchyma: a broad, shallow plate 

always present on the adaxial keel but unconnected to vascular 

bundles; a deeper, irregular plate present on the abaxial keel 

and often with minor bundles wholly embedded in it and the 

median bundle barely or not embedded in it. Lacunae: 

apparently present near the abaxial surface in the ground 

parenchyma in at least one species. Vascular bundle arrangement in the lamina: bundles of the first and third orders present, 

noticeably closer to the abaxial surface. Vascular bundle 

description: first-order bundles ovate; lysigenous cavity 

present; third-order vascular bundles small. Vascular bundle 

sheaths of primary bundles: double sheath present; outer sheath 

of large, thin-walled cells containing few plastids; usually 

incomplete both above and below because of interruptions by 

the sclerenchyma caps, no bundle sheath extensions present; 

inner sheath of two rows of small, achlorophyllous cells with 

uniformly thickened walls, complete. Vascular bundle sheaths 

of third-order bundles: double sheath present, the outer sheath 

of thin-walled cells, interrupted abaxially but usually not 

adaxially by sclerenchyma caps. Sclerenchyma: present as 

strands or caps above and below each vascular bundle; adaxial 

cap few-celled, abaxial cap larger, of cells with thicker walls; 

intercostal sclerenchyma not present. Mesophyll: chlorenchyma 

not radiate, consisting of two layers of cells located 

immediately subjacent to the adaxial epidermis and one layer 

subjacent to the abaxial epidermis, these two layers separated 

by fusoid cells; chlorenchyma cells vertically rectangular in 

basic outline, lacking arm-like extensions but lobed in most 

directions with much intercellular air space; fusoid cells well 

developed; uniseriate columns of chlorenchyma connecting 

adaxial and abaxial chlorenchyma layers and separating 

adjacent fusoid cells. 

ABAXIAL EPIDERMIS (Figure 23).-Costal and intercostal 

zones well differentiated. Intercostal long cells: variable; 

strongly sinuous and rectangular to long, straight-walled, and 

fiber-like. Stomata: typically in rows flanking the veins; 

subsidiary cells low dome-shape or subhexagonal, separated 

by one to several thin-walled interstomatal cells. Bulliform 

cells: absent. Papillae: absent. Prickle hairs: typically absent. 

Microhairs: long, slcndcr, 2-cellcd, typically found in the 

intercostal regions; basal cell curving, often silicified, distinctly 
42 SMITHSONIAN CONTRIBUTIONS TO BOTANY 

shorter than the pointed distal cell and with an apparent 

constriction about one-third of the way up from the base. 

Macrohairs: absent or present, if present commonest along the 

margins of the row of bulliform cells and borne on a prominent 

inflated base. Silica cells: uncommon intercostally, if present 

saddle-shape and projecting above and below the row in which 

developed; common costally, these solitary, paired with cork 

cells, or in short rows, and tending to be more square in outline 

and less saddle-shape. Costal cells in several rows, consisting 

of elongate, slightly sinuous long cells altcrnating with solitary 

or short rows of silica and cork cells. 

ADAXIAL EPIDERMIS (Figure 24).-Basically similar to the 

abaxial epidermis. Bulliform cells: well developed in center of 

intercostal zone; walls sinuous. Intercostal long cells: consistently sinuous, never strongly tapering. Stomata: uncommon 

or absent. Papillae: absent. Prickle hairs: often present in 

intercostal and/or costal regions; consisting of a prominent, 

inflated base and a relatively slender, short prickle. Microhairs: 

present, commonest near margins of the zone of bulliform 

cells. Macrohairs: absent. Silica cells: common, and larger 

than those on the adaxial surface; those in costal regions 

tending to be square rather than saddle-shape. Costal cells: 

similar to those of the abaxial epidermis. 

Inflorescence and Pseudospikelets 

The inflorescence, treated in detail most recently by 

Soderstrom (1981a), is spicate and consists of few to numerous 

(in S. sodiroana) short-pedicelled pseudospikelets arranged 

spirally along the rachis. Each pseudospikelet consists of 12, 

or more commonly 11, bracts arranged spirally on a curving 

axis. The bracts I-V are small, scale-like, and irregular in 

shape, while the upper bracts (except the ninth, which is only 

rarely present) are larger and elongate. Bract VI bears a long, 

FIGURE 23.-Abaxial epidermides of Sfrepfochaefa species: a, S. sodiroana, showing elongate mid-intercostal 

long cells; b, S. spicata subsp. spicafa, showing shorter mid-intercostal long cells with more sinuous walls; c,d, 

S. angustifolia, showing (c) prominent mid-intercostal cilia and (4 bicellular microhairs. (a based on Soderstrom 

1205, Costa Rica; b based on Soderstrom and Calderon 1861, Brazil; c, d based on Soderstrom and Sucre 

1969, Brazil.) Scale bar: a = 60 p: b = 70 p; c = 80 pm; d = 20 p. 
NUMBER 68 43 

tendrilous awn, and the seventh and eighth bracts are inserted 

nearly side-by-side and have slightly recurved apices. Bract 

IX is only rarely present. Bracts X-XI1 are of nearly identical 

morphology and tightly invest the flower, which consists of six 

stamens (often delicately fused into a tube, at least near the 

base), and a gynecium with 3 hispid stigmas. 

Fruit 

STARCH GRAINS.-The endosperms of Streptochaeta sodiroana and S. spicata subsp. spicata are charactcrized by 

elliptical, highly compound grains, with 15-30 grains occurring in each endosperm cell. Each grain is 10-25(50) pm in 

diameter and is composed of 50-300 strongly angular granules 

that are approximately 2-4 pm in diameter. 

EMBRYO.-Sections of the embryos of several specimens 

of S. sodiroana and S. spicata subsp. spicata (Figure 13a,b) 

show that in median sagittal sections no mesocotyledonar 

internode is present between the scutellar and coleoptilar nodes 

of the vascular bundle 0, no trace of an epiblast is present 

(-), a small, shallow cleft is present between the lower part of 

the scutellum and the coleorhiza (P), and the embryonic leaf 

margins appear to overlap (P), giving a formula of F - PP (in 

the formula of Reeder, 1957). At least the margins of the 

coleoptile are not fused in the upper portions and there is a 

hint that they overlap. Five nerves were noted in the basal 

portion of the coleoptile and three in the first embryonic leaf. 

CHROMOSOMES 

There have been three gametic chromosome counts for two 

species of Streptochaeta: Pohl and Davidse (1971) and 

FIGURE 24.--Leaf epidermides of Streplocheta species: a,b, adaxial view of S. sodiroana showing (a) bulliform 

cells (below) and (b) structure of costal and isolated intercostal silica cells; c, adaxial view of S. angustifofia 

showing poorly differentiated bulliform cells; d, abaxial, S. spicata subsp. spicata, showing bicellular microhairs 

(arrows). (a, b based on Soderstrom 1205, Costa Rica; c based on Soderstrom and Sucre 1969, Brazil; d based 

on Soderstrom and Calderon 1861, Brazil.) Scale bar: a = 100 pm; b,d = 40 p; c = 120 pm. 
44 SMITHSONIAN CONTRIBUTIOKS TO BOTANY 

Hunziker et al. (1982) studied S. sodiroana, and Valencia 

(1962) studied S. spicata subsp. spicata. All report that n = 

11 with perfect pairing of bivalents. 

DISCUSSION 

Habit 

Species of Streptochaeta are forest understory herbs to 1 

meter tall. The plants are generally cespitose (Figure la) but 

apparently it is possible for a culm to become lodged in the 

soil, develop adventitious roots at the nodes, and spread 

vegetatively. Unlike Anomochloa, the culms of Streptochaeta 

are promincnt and leafy and thc lcaf phyllotaxy rcprcscnts a 2/5 

or 3/s spiral of a type rare in grasscs (Page, 1951). In all taxa 

except S. sodiroana the upper portion of the culms may 

rebranch in a secund manner with each branch terminating in 

an inflorescence. Prominent prophylls are present as the first 

appendage of each lateral branch in such cases, but these organs 

are many-nerved, not bicarinate as are the prophylls of most 

grasses. The last leaf or two preceding the inflorescence is 

invariably a sheath lacking a blade. 

The leaf sheaths of the plants are open. Neither an internal 

nor external ligule is found at the summit of the sheath, but 

lateral appendages of a type described for other bamboos by 

Tran Van Nam (1972) and minute oral setae are present, as is 

a prominent, turgid, hairy pulvinus. Cross-sections of the 

pulvinus reveal a complex vascular structure roughly similar 

to that of the upper pulvinus of Anomochloa. The blades of 

Streptochaeta are promincntly tessellate and have a basically 

parallcl venation. However, the venation is oblique to the 

extent that vcins converge into the midrib for a distance of 

several centimeters above the base of the lamina. 

Leaves 

Cross-sections of the leaf bladcs of Streptochaera reveal 

prominent fusoid cells and a distinctive midrib morphology, 

first noted by Metcalfe (1960:488), in which the adaxial keel 

is flat-topped and prominent while the abaxial keel is 

dome-shape. The midrib retains its peculiar morphology and 

complex vasculature to near the apex of the blade. The 

devclopment of the fusoid cells in S. spicata was studied by 

Page (1947). 

The epidermides of Streptochaeta (Figures 23, 24) bear 

several resemblances to the bambusoid core group. The long 

cells are clongate with straight walls (S. sodiroana) to 

rectangular with sinuous walls, depending on the epidermis 

and species. Bulliform cells are well developed on the adaxial 

epidermis but epidermal papillae are totally lacking. Intercostal 

silica-cork cell pairs, characteristic of most bambusoid grasses, 

are absent in Streptochaeta. Streptochaeta has silica cells of a 

single type, vertical saddle-shape, although those silica cells 

found in the costal zones are smaller than the prominent 

isolated ones found in the intercostal zones. By contrast, 

Anomochloa has three types of silica cells (costal; intercostal 

associated with cork cells; and isolated intercostal), all with 

different morphologies. 

The microhairs of Streptochaeta are 2-celled and vary in 

length from 75-150 pm. The apical cell is about half again as 

long as the basal cell and is narrowly elliptic to linear, with a 

somewhat pointed apex (Figures 23d, 246). The microhairs of 

the examined specimen of S. spicata subsp. ecuatoriana were 

remarkable for their very large size (120-150 pm), and in fact 

were half again as long as those of the other three species as 

noted both in our study and the survey of Metcalfe (1960:487). 

Based on a review of the grasses treated by Metcalfe (1960) 

and Tateoka et al. (1959), as well as our own studies, it appears 

that the bicellular microhairs of S. spicata subsp. ecuatoriana 

are the longest of any grass. The herbaceous bamboo 

Guaduella has microhairs approaching 250 pm in length 

(Metcalfe, 1960:487; personal observation) but these hairs are 

multicellular, not bicellular. Tateoka and Takagi (1967) found 

that the microhairs on the epidermis of the “lodicules” (spikelet 

bracts X-XII) of S. spicata have an apical cell much shorter 

than the basal cell. 

The three species of Streptochaeta differ in the abaxial leaf 

blade epidermides (Table 1). Leaves of S. sodiroana possess 

elongate, nearly straight-walled, tapering mid-intercostal long 

cells (Figure 23a) reminiscent of those of Streptogyna species 

(Soderstrom et al., 1987) and these are set off sharply from the 

interstomatal long cells, which are rectangular with strongly 

sinuous walls. In S. spicata there is barely any differentiation 

of the mid-intercostal long cells and interstomatal cells; both 

are rectangular with sinuous walls (Figure 23b). 

The abaxial intercostal region of Streptochaeta angustifolia 

(Figure 23c) is differentiated into a central zone of rectangular, 

sinuous-walled long cells (these interspersed with ciliate 

macrohairs) flanked by two zones of elongate, slightly tapering 

long cells, and a zone of interstomatal cells that are 

elongate-rectangular with moderately sinuous walls. Cilia with 

broad inflated bases are common in the mid-intercostal regions 

of S. angustijolia, as are prickles. Both of these features, 

however, are rare or absent in S. spicata and are never seen in 

S. sodiroana. The abaxial epidermis of S. sodiroana exhibits 

occasional large, isolated silica cells enclosing ellipsoidcrenate silica bodies, a feature not observed in the abaxial 

intercostal zones of the other three species. Sfreptochaeta 

sodiroana has more rows of stomates flanking the veins than 

the other taxa. 

The adaxial epidermis exhibits less interspecific differentiation, but the stomates appear to be randomly scattered in S. 

sodiroana but only occur in zones flanking the veins in S. 

spicata. Also, both epidermides of S. sodiroana lack prickles, 

a feature that has been observed in at least one epidermis in 

the other three taxa. 

Inflorescence and Pseudospikelets 

The inflorescences and pseudospikelets of Streptochaeta 

have been the objects of detailed studies, the most recent of 
NUMBER 68 45 

TABLE l.-Comparison of leaf epidermal anatomy of Streptochaeta species. 

S. suicata 

Character S. sodiroana ssp. ecuatoriana ssp. spicata S. angustifolia 

LOWER (AB~L) 

EPIDERMIS: 

Intercostal long cells Elongate; 

walls not sinuous 

Elongate-rectangular, 

walls sinuous 

Rectangular, 

walls strongly sinuous 

Elongate-rectangular 

walls moderately sinuous 

Rows of stomates flanking 

each side of vein 

Interstomatal long cells 

B icellular microhairs 

(length in pm) 

7-9 2 24 2or3 

Very sinuous Moderately sinuous Moderately sinuous Not sinuous 

Present only in 

stomata1 regions 

(75-90) 

Present in all 

intercostal regions 

(1 20-150) 

Present in all 

intercostal regions 

(85-1 05) 

Present in all 

intercostal regions 

(90-1 15) 

Macrohairs Absent Absent Rarely present Present, mostly in 

center of intercostal mne 

Intercostal prickles 

Costal prickles 

and microhairs 

Vein spacing (mm) 

Costal short cells 

Absent 

Absent 

Common Common 

Absent 

Absent 

Absent Present 

0.7-0.9 0.7-0.8 0.4-0.6 0.3-0.4 

Solitary, paired, or 

in threes 

Solitary, paired, or 

in threes 

Solitary, paired, or 

mostly in short rows 

(3-8 cells) 

Solitary, paired. or 

mostly in short rows 

(3-8 cells) 

Intercostal silica cells Present Absent Absent Absent 

UPPER (ADAXIAL) 

EPIDERMIS: 

Stomates Scattered throughoi 

intercostal areas 

Uncommon, in rows 

flanking veins 

Uncommon, in rows 

flanking veins 

Moderately large, only 

very close to veins 

Edges of and among 

bulliform cells 

Rare 

Intercostal silica cells Very large, saddle-shaped, 

in intercostal areas 

Uncommon, near veins Uncommon, near veins 

Prickles Absent Absent Edges of (but not among) 

bulliform cells 

Bicellular microhairs Throughout intercostal 

zone, but not among 

bulliform cells 

Edges of me of 

bulliform cells 

Edges of (rarely among) 

zone of bulliform cells 

Edges of mne of 

bulliform cells 

which have been Page (1951) and Soderstrom (1981a); both 

are recommended for their reviews of the many previous 

studies of this genus. Soderstrom interpreted the spikelet-like CARY0PSIS.-The hila in the caryopses of Streptochaeta 

diaspores as consisting of a series of “bracts on different axes spicata subsp. spicata and S. sodiroana are quite different in 

of a highly modified pseudospikelet,” basing this view on morphology; in the former the hilum is strictly linear (Figure 

(among other features) the occasional presence of buds in the 200) while in the lattc there is an elliptical trough occupying 

axils of bracts I-V and the anomalous structure and the center of the ventral face (Figure 17q). This is interesting 

arrangement of the putative “lodicules” (bracts X-XI I). in that hilum morphology is generally considered to be a 

Fruit 
46 SMITHSONIAN CONTRIBUTIONS TO BOTANY 

conservative character even at the subfamilial level in the 

Poaceae. The Bambusoideae are usually considcrcd to be 

characterized by a strictly linear hilum (Calderbn and 

Soderstrom, 1980: 11). However, nonlinear hila somewhat 

resembling the type found in S. sodiroana are known from 

species of the olyroid genera Raddiella (Calderbn and 

Soderstrom, 1967, fig. 9a) and Diandrolyra (Soderstrom and 

Zuloaga, 1985, fig. lo). 

STARCH GRAINS.-The endosperm starch grains of Streptochaeta spicata were first studied by Yakovlev (1950, fig. 20), 

who illustrated them as strongly compound. Tateoka (1962) 

studied an unspecified species of Streptochaeta and reported 

that the grains were of his Type IV; that is, strictly compound 

with eight to numerous granules in each grain. He noted that 

this type is typical of festucoid, eragrostoid, and oryzoid 

grasses, and that the olyroid herbaceous bamboos show a 

similar type that differed in having only 3 to 10 granules per 

grain. Our findings of highly compound grains for both S. 

sodiroana and S. spicata confirm these studies. 

EMBRYO.-Yakovlev’s (1950, fig. 78) illustration of a 

longitudinal section of the embryo of Streptochaeta spicata 

shows a cleft between the scutellum and the coleorhiza, no 

mesocotyledonar internode, and no evident epiblast. The 

embryo of the same species was studied in detail by Reeder 

(1953), who reported that Streptochaeta was unique among 

grasses in possessing a coleoptile with unfused, overlapping 

margins and 5 nerves. He recorded the presence of a short 

midnerve but noted that it was not prominent and disappeared 

soon above the base. Reeder was also impressed by the 

unfused, overlapping margins of the coleoptile. Most bambusoid grasses examined have coleoptiles with margins that 

are unfused for at least part of their length and some have the 

free portions of these margins overlapping (Ghopal and Ram, 

1985; Usui, 1957; Philip and Haccius, 1976; de la Cruz, 1985; 

X. Londono (Instituto Vallecaucano de Investigaciones 

Cientificas, Cali, Colombia; pers. comm.) for a fleshy-fruited 

species of Guadua; sections by the present authors of most 

olyroid and pharoid genera). Later, in general surveys of grass 

embryos, Reeder (1962) reported a formula of F - PP for 

Streprochaera, that is, typically bambusoid except for the 

absence of an epiblast. No other bambusoid grasses are known 

that lack an epiblast, except possibly for some woody, 

fleshy-fruited Indian species (Ghopal and Ram, 1985). Our 

sections of the embryos of several specimens of S. sodiroana 

and S. spicata confirm the findings of Yakovlev (1950:195) 

and Reeder (1953). 

rachis and become intertwined with the bract VI awns of the 

other pseudospikelets in a tangled, oftcn pendent mass (Figures 

la, 16a, 19a) adapted for external animal dispersal (epizoochory; Ridley, 1930, Van der Pijl, 1982). In S. spicata the 

upper part of the rachis and the pedicels of the pseudopetioles 

are covered with hooked hairs (Figure 20a) that aid in securing 

the spikelets by the bract VI awns. The pseudospikelets then 

serve as diaspores that become entangled, often en masse, in 

the fur of mammals or in clothing; the Schipp collection of S. 

sodiroana from Belize bears the comment that the species is 

“one of the worse grass pests we have in the colony.” The 

slightly recurved apices of bracts I-V, VII, and VIII may help 

to secure the pseudospikelet in the pelage of the disperser. 

Interspecific Relationships 

Streptochaeta sodiroana is quite distinct from the taxa of 

the S. spicata group. The depressed, trough-like area in the 

hilum of the caryopsis, the fiber-like mid-intercostal long cells 

on the abaxial leaf epidermis (Figure 23a), and the absence of 

foliar prickles may all be interpreted as specializations when 

S. sodiroana is compared with possible outgroups of the genus, 

such as Anomochloa or the Olyreae. Members of the S. spicata 

group also have some specializations: branched culms; the 

tendency of the andrecium to form a stamen tube; the presence 

of hooked hairs on the pedicels of the pseudospikelets and 

summit of the rachis; and the restriction of bicellular microhairs 

on the adaxial leaf epidermis to the areas immediately adjacent 

to the bulliform cells. The presence of these apomorphic 

characters may indicate that neither group is directly ancestral 

to the other. 

Phylogenetic Position of Anomochloa and Streptochaeta 

The affinities of Anomochloa marantoidea have long 

puzzled agrostologists. Brongniart (185 1) suggested that 

Anomochloa might be related to the Oryzeae, based on its 

resemblance to Oryza in its many-nerved (according to his 

interpretation) palea, possession of more than three stamens, 

and I-flowered, terminal spikelets without glumes. Lacking 

material for further studies later authors had to concur with 

this placement (Doell, 1871:24; Hackel, 1887:42; Baillon, 

1893:297; Schuster, 1909:32), although Bentham (1883:1111) 

tentatively placed the genus, along with other herbaceous 

bamboos, in the Paniceae. Early and mid-twentieth century 

agrostologists emphasized the distinctiveness of Anomochloa. 

Hubbard (1934:219) erected the tribe Anomochloeae for the 

genus but did not allocate any of his tribes to subfamilies. 

Pilger (ex Potztal, 1957) placed it in its own subfamily, the 

Anomochlooideae. Exceptions to this trend of recognition at 

successively higher taxonomic levels were Stapf (1898) and 

Roshevits (1937: 199), who placed Anomochloa in the Phareae, 

along with several olyroid genera. The anatomical work of 

At maturity the pseudospikelets become detached from the Page (1947) and Metcalfe (1960:29) revealed that the 

Reproductive Biology 

Observations of Streptochaeta sodiroana at La Selva, Costa 

Rica, in February 1983 indicated that the pseudospikelets 

bloomed protogynously and in a basipetal sequence in the 

inflorescence. 
NUMBER 68 47 

epidermal and cross-sectional leaf anatomy of Anomochloa, 

with its prominent fusoid cells, was similar to the bamboos. 

Later authors (Calderon and Soderstrom, 1980: 16; Watson et 

al., 1985:460; Clayton and Renvoize, 1986:57), therefore, have 

maintained the plant in its own tribe within the Bambusoideae. 

The highly bracteate nature of the inflorescence of 

Streptochaeta has long hinted at its affinities to the woody 

bamboos, as recognized by Nees von Esenbeck (1835), who 

placed the genus in a group that corresponds to the modern 

broad view of the Bambusoideae. Both Steudel(1855:339) and 

Doell (1877:217) agreed that the affinities of Streptochaeta 

were, if anything, to the bamboos. Most later 19th century 

authors, however, placed the genus in either the Oryzeae 

(Hackel, 1887:42; Baillon, 1893:296) or Paniceae (Kunth, 

1833:164; Bentham, 1883:llll). In the present century most 

agrostologists have placed the genus close to the bamboos. 

Hubbard (1934:205) placed Streptochaeta in its own tribe, the 

Streptochaeteae, near the Bambuseae, and Roshevits (1937: 157) 

included the tribe in his “Series Bambusiformes” along with 

the Phareae and Bambuseae. Subsequent authors (Parodi, 1961; 

Soderstrom, 1981a: 17; Clayton and Renvoize, 1986:58) have 

recognized this grass as a monotypic tribe and included it in 

the Bambusoideae, although Butzin (1973: 121) established the 

Streptochaetoideae with the Streptochaeteae as its only tribe. 

Most evidence of relationships of Anomochloa and Streptochaeta to other herbaceous bamboos is of a negative nature, 

that is, two or more of the tribes often lack a feature found in 

the others. For example, the Anomochloeae, Streptochaeteae, 

Phareae, Streptogyneae, and Puelieae lack the prominent 

epidermal papillae and well-developed arm cells found in the 

B ambuseae, B uergersiochloeae, Olyreae, G uaduelleae, and 

many oryzoids; Anomochloa and Streprochaeta lack the 

membranous inner ligules found in all other bambusoids except 

for the African Puelia schumanniana, which is highly 

specialized. Because of the possibility of indcpcndcnt loss, 

however, the shared absence of a feature is not as strong an 

indication of relationship as the shared presence of a derived 

c harac ter. 

There are some characters that may indicate a distant 

relationship between Streptochaeta and Anomochloa and the 

olyroid bamboos. A single meiotic chromosome count has 

been made €or Anomochloa marantoidea recently, and a 

gametic number of n = 18 has been observed (J.H. Hunziker 

and A. Wulff, pers. comm.). The chromosome number of n = 

18 is uncommon but scattered in the grass hmily. Joinvillea 

(Joinvilleaceae), which has been suggested as closely related 

to the grasses (Dahlgren et al., 1985:425; Campbell and 

Kellogg, 1987), however, has an identical count (Newell, 

1969). It is interesting to note that the only bambusoid grass 

known with a chromosome numbcr equaling half that of 

Anomochloa is the olyroid Diandrolyra bicolor (n = 9; Dakcr, 

1968). Thc basic number of Streptochaeta (n = 11) is quite 

common in the Olyreae. Bcsidcs its similar basic chromosome 

numbcr, Lhc seedling of S. spicata subsp. spicata is of the 

typical olyroidjbambusoid type, with a few bladcless or 

reduced-leafy sheaths preceding the first fully developed leaf, 

which bears a broad, horizontal lamina (Soderstrom, 1981a:24). 

The highly compound starch grains of both Anomochloa and 

Streptochaeta are common in the Oryzeae and in several 

olyroid genera, such as Maclurolyra (Calderbn and Soderstrom, 1973, fig. 140. Compound grains of this type are also 

found in Joinvillea (Joinvilleaceae; personal observation) and 

Restio (Restionaceae; Yakovlev, 1950, fig. 39), both putative 

relatives of the grasses. The isolated intercostal silica cells of 

Anomochloa enclose typical olyroid (vertical-crenate) silica 

bodies; silica-cork cell pairs are common throughout the 

intercostal zones, as in the many olyroids; the partial 

inflorescences recall those of many olyroid genera (cf. 

Calderon and Soderstrom, 1973, fig. 11); and the leaf venation 

is of the parallel type found in the olyroids. 

Streptochaeta bears less of a resemblance to the Olyreae in 

exhibiting a distinctly oblique type of leaf venation (at least 

in the lower quarter of the blade) never found in the olyroids 

but found in the African tribe Puelieae, and especially well 

developed in the Phareae. The leaves have vertical silica bodies 

of a saddle-shape type, rather than the crenate type found in 

the olyroids; the embryo of Streptochaeta lacks an epiblast, 

which is found in all olyroid genera examined. 

It is natural to begin the search for a sibling group of 

Anomochloa with Streptochaeta, because both genera are the 

only herbaceous bamboos that have inflorescences and 

spikelets (or the functional equivalents of spikelets) that are 

difficult to interpret in conventional agrostological terms. 

Further study, however, has made it clear that the inflorescences and spikelets of the two genera have little in common. 

The spikelet-equivalent in Streptochaeta is a pseudospikelet 

composed of 12 spirally arranged bracts (Soderstrom, 1981a, 

fig. 8j), and the pseudospikelets are borne spirally in a 

spike-like arrangement. We have shown that in Anomochloa 

the 2-bracted spikelets, exccpt for the solitary terminal one, are 

borne in alternating scorpioid cyme-like partial inflorescences 

subtended by prominent general bracts. 

Anomochloa and Streptochaeta share features of leaf 

anatomy and fruit morphology that may qualify as sharedderived characters (synapomorphies). 

1. A similar leaf midrib structure in which the keel projects 

both abaxially (as a small dome) and adaxially in a prominent 

‘anvil‘ or ‘keystone‘ configuration. This distinctive morphology has not been found in any other bambusoid genus studied 

by us. Both genera also have a complex vasculature, 

Streptochaeta along the entire length of the blade, Anomochloa 

in at least the lower half. 

2. Exceptionally large (75-150 pm long) bicellular microhairs of a distinctive type, with the pointed apical cell 

averaging at least half again as long as the basal cell and with 

the basal cell having an apparent constriction about one-third 

of the way from the base (also a feature not seen in other 

bamboos). Most bambusoid grasses have microhairs ranging 

from 40-75 pm in length, with the unconslricted basal cell 

longer than the blunt apical cell (Metcalfe, 1960, fig. 16). 
48 SMITHSONIANCONTRIBUTIONS TO BOTANY 

3. Isolated, vertically elongated silica cells on the leaf 

epidermis. Isolated intercostal short cells that project above 

and below the file in which they are borne are typical of the 

Olyreae, but in that tribe they never project so prominently 

above and below the file in which they are situated as they do 

in Anomochloa and Streptochaeta. 

4. Strongly compound starch grains of a type common in the 

Oryzeae but less common in the core group of the 

Bambusoideae. 

5. Five-nerved coleoptiles with unfused margins in which 

the midnerve is soon lost distally, although recent anatomical 

studies of woody bamboos have revealed that several have 

many-nerved coleoptiles with at least partially unfused margins 

(Ghopal and Ram, 1985). 

These five features may constitute evidence for a relatively 

close relationship between Anomochloa and Streptochaeta. It 

must be emphasized, however, that in many ways besides 

inflorescence and spikelet structure the two genera are amply 

distinct from each other, including significant differences in 

chromosome number (n = 18 and n = 11, respectively), embryo 

structure (epiblast present in Anomochloa but absent in 

Streptochaeta), and leaf epidermal anatomy (typical silica cells 

crescent to roundish in Anomochloa, tall saddle-shape in 

Streptochaeta); the phenetic studies of Watson et al. (1985463) 

have led them to place Streptochaeta in their supertribe 

Bambusanae (with the woody bamboos and the severalflowered herbaceous bamboo tribes) and Anomochloa in their 

Oryzanae (with the single-flowered tribes of herbaceous 

bamboos). Based on their common possession of 1-flowered 

spikelets, symmetrical, predominantly adaxially projecting leaf 

midribs, herbaceous culms, and noncyclic flowering, Soderstrom and Ellis (1987) place the Anomochloeae and Streptochaeteae in their supertribe Olyrodae, along with the Olyreae 

and Buergersiochloeae. We still must examine the seedling of 

Anomochloa before coming to definite conclusions about its 

affinities. Despite its bizarre inflorescence, the leaf anatomy 

and embryo structure of Anomochloa marantoidea are not so 

different from that of the olyroid grasses. "he species is 

definitely a member of the grass family. 
Literature Cited 

Arber, A. 

1929. 

1934. 

Baillon, H. 

1893. 

Studies in the Gramineae, VI: 1, Streptochaeta; 2, Anomochloa; 3, 

Ichnanthus. Annals of Botany (London), 43:35-53.7 figures. 

The Gramineae: A Study of Cereal, Bamboo, and Grass. 480 pages, 

212 figures. Cambridge, England: The University Press. 

Hbtoire des plantes: Monographie des graminees. 334 pages, 119 

figures. Paris: Librairie Hachette & Cie. 

Gramineae. In G. Bentham and J.D. Hooker, Genera Plantarum, 

3(2):1074-1215. London: Lovell, Reeve, and Co. [Streptochaeta 

on pages 1078 and 111 1.1 

Enumeration des genres de plantes cultieb au Museum D'Histoire 

Naturelle de Paris. 237 pages. Paris: J.-B. Bailliere. 

Description d'un nouveau genre de Graminees du Bresil. Annales 

des Sciences Naturelles, Botanique (Paris), series 3, 16:368-372, 1 

plate. 

Die Namen der Supragenerischen Einheiten der Gramineae (Poaceae). 

Willdenowia, 7:113-168. 

1967. Las gramineas tropicales afines a "Olyra" L. In Atas do Simodsio 

sobre a Biota hzdoica, 4(Botanica):67-76, 10 figures. 

1973. Morphological and Anatomical Considerations of the Grass 

Subfamily Bambusoideae Based on the New Genus Maclurolyra. 

Smithsonian Contributions to Botany, 11:l-55, figures 1-24. 

The Genera of the Bambusoideae (Poaceae) of the American 

Continent: Keys and Comments. Smithsonian Contributions to 

Botany, 44: 1-27. 

Bentham, G. 

1883. 

Brongniart, A. 

1850. 

1851. 

Butzin, F. 

1973. 

Calderon, C.E., and T.R. Soderstrom 

1980. 

Campbell, C.S. 

1985. The Subfamilies and Tribes of Gramineae (Poaceae) in the 

Southeastern United States. Journal of the Arnold Arboretum, 

66(2):123-199. 

Campbell, C.S., and E.A. Kellogg 

1987. Sister Group Relationships of the Poaceae. In TR. Soderstrom, 

K.W. Hdu, C.S. Campbell, and M.E. Barkworth, editors, Grass 

Systematics and Evolution, pages 217-224. Washington, D.C.: 

Smithsonian Institution Press. [Proceedings of the International 

Symposium IIcld at the Smithsonian Institution, Washington, D.C., 

27-31 July 1986.1 

Celakovskyr, L. 

1889. Uber den Archenbau der Brasilianischen Grasgatung Streptochaeta 

Schrader. Sitzungsberichte der Koniglichen Bokchen Gesellschaflder 

Wbsenschafen. Mathematisch-natwwissenschaf liche Classe, 3 : 14- 

42, table 2. [Unpublished English translation by Mrs. Geti Saad, 

1974, for the Smithsonian Institution and National Science 

Foundation, Washington, D.C.; in the files of the McClure Bamboo 

Library, Department of Botany, Smithsonian Institution, Washington, D.C.1 

Clayton, D.K,. and S.A. Renvoize 

1986. Genera Graminum. 389 pages. London: Her Majesty's Stationary 

Office. 

Spikelet and Floral Morphology. In TR. Soderstrom, K.W. Hilu, 

C.S. Campbell, and M.E. Barkworth, editors, Grass Systematics and 

Evolution, pages 21-30, 1 figure, 2 tables. Washington, D.C.: 

Clifford, H.T 

1987. 

Smithsonian Institution Press. [Proceedings of the International 

Symposium Held at the Smithsonian Institution, Washington, D.C., 

27-31 July 1986.1 

Dahlgren. R.M.T., H.T. Clifford, and P.F. Yeo 

1985. The Families of the Monocotyledons. 520 pages, 225 figures. Berlin: 

Springer-Verlag. 

Karyotype Analysis of Diundrolyra bicolor Stapf (Gramineae). Kew 

Bulletin, 21:433434. 

Fruit Dispersal in the Poaceae. In T.R. Soderstrom, K.W. Hilu, C.S. 

Campbell, and M.E. Barkworth, editors, Grass Systematics and 

Evolution, pages 143-155, 2 figures, 4 tables. Washington, D.C.: 

Smithsonian Institution Press. [Proceedings of the International 

Symposium Held at the Smithsonian Institution, Washington, D.C., 

Daker, M.G. 

1968. 

Davidse, G. 

1987. 

27-31 July 1986.1 

de la CNZ, G.A. 

1985. Anatomia y morfologai del fruto y semilla de Olmeca. 59 pages, 

23 figures. Masters thesis, Institucion de Ensenanza e Investigaciones en Ciencias Agn'colas. 

Morfologicheskiye osobennosti lodikul u nekotorykh predstavitelej 

semejstva zlakovykh. [Morphological Peculiarities of Lodicules in 

Some Representatives of the Grass Family.] Trudy Botanischeskogo 

Institua im. V.L., Komarova Akademii Nauk SSSR, seriya 7 

(Morfologiya i Anatomiya Rastenii), 5:148-165. [Unpublished 

English translation by M. Kovanda, 1971, in the files of the McClure 

Bamboo Library, Department of Botany, Smithsonian Institution, 

Washington, D.C.] 

Tribes 1-2, Oryzeae and Phalarideae. In C.F.P. von Martius, editor, 

Flora Brasiliensis, 2(2):1-32, plates 1-1 1 (fascicle 51). Munich, 

Vienna. [14 volumes (in 40) published in 130 fascicles between 

1840-1906.1 

1877. Tribe 11, Bambusaceae. In C.F.P. von Martius, editor, Flora 

Brasiliensb, 2(3):161-220, plates 44-56 (fascicle 83). Munich, 

Vienna. 

A Taxonomic Revision of Buergersiochloa Pilger (Gramineae). 

Blumea, 22:415418. 

A New Genus and Two New Species of Cecidomyiidae Associated 

with Pariuna Species (Gramineae) in South America (Diptera). 

Proceedingsof the Entomological Society of Washington, 71 (1):108- 

111. 

1985. Systematic Significance of Mature Embryo of Bamboo. Plant 

Systematics and Evolution, 148:239-246. 

Hackel, E. 

1887. Gramineae. In A. Engler and K. Prantl, editors, Die Naturlichen 

Pflanzenfamilien, 2(2):1-97. Iipzig: W. Engelmann. 

1890. Eine zweite An von Streptochaeta; St. sodiroana sp. nov. 

Oesterreiche Botaniche Zeitschrifl, 4O:lll-114. 

1981. Index Herbariorum, Part I: The Herbaria of the World. 7th edition, 

452 pages. Utrecht: Bohn, Scheltema, and Holkema. 

Dobrotvorskaya, A.V. 

1962. 

Doell, J.C. 

1871. 

Fijten, F. 

1975. 

Gagnb, R.J. 

1969. 

Ghopal, B.H., and H.Y. Mohan Ram 

Holmgren, P.K., W. Keuken, and E.K. Schofield 

49 
50 SMITHSONIAN CONTRIBUTIONS TO BOTANY 

Hooker, W.J. 

1862. Anomochloa marantoidea. Maranta-like Anomochloa. In Curtis’s 

Botanical Magazine, series 3, volume 18, tabula 5331. 

Gramineae. In J. Hutchinson, The Families of Flowering Plants, 

2(Monocotyledons): 199-229. London: Macmillan. 

Chromosome Studies on the Bambusoideae (Gramineae). Brittonia, 

Kubbard, C.E. 

1934. 

Hunziker, J.H., A.F. Wulff, and T.R. Soderstrom 

1982. 

34( 1):30-35. 

Judziewicz, E.J. 

1987. 

Kunth, C.S. 

1833. 

Taxonomy and Morphology of the Tribe Phareae. 529 pages. 

Doctoral dissertation, University of Wisconsin, Madison. 

Enumeratio Plantarum. Volume 1,606 pages; volume 2,436 pages, 

39 plates. Stuttgart: J.G. Cottae. 

Anatomy of the Monocotyledons. I. Gramineae. lxi + 731 pages, 29 

figures. Oxford: Clarendon Press. 

Culture des Orchidees, contenant des instructions sur leur recolee, 

expedition et mise en etgetation avec une hte descriptive d’environ 

550 especes et varetets clasedes par ordre a2 eerite. viii + 196 

pages. Paris: Dusacq, Librairie Agricole de la Maison Rustique. 

The Herbarium of the “Centro de pesquisas do cacau” at Itabuna, 

Brazil. Brittonia, 31(2):177-196. 

Metcalfe, C.R. 

1960. 

Morel, C. 

1855. 

Mori, S.A., and L.A. Silva 

1979. 

h’ees von Esenbeck, C.G.D. 

1829. Gramineae, a Neesio ab Esenbeck expositae. [Alternate title: 

Agrostologia brasiliensis, seu descripto gramineae in imperio 

brasiliensi hucusque detectorurn.] In C.F.D. von Martius, Flora 

brasilienis. Volume 2, part 1, iii + 608 pages. Stuttgart and 

Tubingen: J.G. Cottae. 

Bambuseae Brasilienses. Recensuit, et Alias in India Onentali 

Provenientes Adjecit. Linnaea, 9:461-494. 

Genera [of Grasses]. In I. Lindley, A Natural System of Botany; or, 

A Systematic View of the Organisation, Natural Affinities, and 

Geographical Dirtribution, of the Whole Vegetable Kingdom .... xxvi + 526 pages. London: Longman, Rees, Orme, Brown, Green, 

and Longman. 

A Study of the Genus Joinvillea (Flagellariaceae), Journal of the 

Arnold Arboretum, 50:527-555. 

El problema de la palea de Oryza L. Boletin de la Sociedad 

Argentina de Botanica, 1257-97. 

Leaf Anatomy of Streptochaeta and the Relation of This Genus to 

the Bamboos. Bulletin of the Torrey Botanical Club, 74232-239. 

Morphology of the Spikelet of Streptochaeta. Bulletin of the Torrey 

Uotanical Club, 78(1):22-37. 

1835. 

1836. 

Newell, T.K. 

1969. 

Nuiiiz, 0. 

1968. 

Page, V.M. 

1947. 

1951. 

Parodi, L.R. 

1961. La taxonomii de las Gramiieas Argenthas a la luz de las 

investigaciones mas recientes. Recent Advances in Botany, 1: 125- 

130. 

Embryogenesis in Bambusa armdinacea Willd. and Structure of the 

Mature Embryo. Beitraa zur Biologie der Pflanzen, 52:83-100. 

[Embryogenesis of Arundinaria alpina K. Schumann also described.] 

Das System der Gramineae unter Ausschluss der Bambusoideae. 

Botanische Jahrbuuher fur Systematik, Pflanzengeschichte und 

Pflanzengeographie, 76(3):28 1-384. 

Chromosome Numbers of Costa Rican Grasses. Brittonia, 23:293- 

324. 

Philip, V.J., and B. Haccius 

1976. 

Pilger, R. 

1954. 

Pohl. R.W., and G. Davidse 

1971. 

Potztal, E. 

1957. Beschreibungen einiger systematischer Gruppen der Graser. Willdenowia, 1 :77 1-772. [Anomochloideae Pilger ex Potztal validated.] 

1866. Iconum Botanicarum IndexLocupletissimus. Edition 2; part 1,1184 

pages. Berlin: Effert and Lindtner. 

Reeder, J.R. 

1953. The Embryo of Steptochaeta and Its Bearing on the Homology of 

the Coleoptile. American Journal of Botany, 40:77-80. 

1957. The Embryo in Grass Systematics. American JOWMI of Botany, 

44:75&768. 

1962. The Bambusoid Embryo: A Reappraisal. American Journal of 

Botany, 49:639-641. 

A Survey of Leaf-blade Anatomy in Grasses, V: The Bamboo Allies. 

Kew Bulletin, 40(3):509-535. 

The Dispersal of Plants Throughout the World. 744 pages. Ashford, 

Kent, England: L. Reeve. 

Pritzel, G.A. 

Renvoize, S.A. 

1985. 

Ridley, H.N. 

1930. 

Roshevits, R. Yu. 

1937. Zlaki: Vvedenie v Izuchenie Kormovykh i Khlebnykh Zlakov. 

[Grasses: An Introduction to the Study of Fodder and Cereal 

Grasses.] vi + 635 pages. Moscow, Leningrad: Sel’khozgiz, 

Gosudarstvennoe Izdatel’stvo Kolkhoznoi i Sovkhoznoi Literatury. 

Agricultural Publishing House. [New Delhi: English translation 

published for the Smithsonian Institution and the National Science 

Foundation, Washington, D.C., 1980. NTIS no.: TTH 72-51033.1 

Uber die Morphologie der Grasblufe. 56 pages, 35 figures, 4 tables. 

Jena: Gustav Fischer. [This preprint was subsequently published in 

1910 in Flora, 100:213-266, plates 2-5. English translation 

prepared for the Smithsonian Institution and the National Science 

Foundation, Washington, D.C., by Saad Publications, Karachi, 

Pakistan, 1980. 69 pages. Housed in the Hitchcock and Chase 

Library, Department of Botany, Smithsonian Institution.] 

1980. A New Species of Lithachne (Poaceae: Bambusoideae) and Remarks 

on Its Sleep Movements. Brittonia, 32(4):495-501. 

1981a. Some Evolutionary Trends in the Bambusoideae (Poaceae). Annals 

of the Missouri Botanical Garden, 68:15-47, figures . 1981b. Sucrea (Poaceae: Bambusoideae), a New Genus from Brazil. 

Brittonia, 3 3 (2) : 198-2 1 0. 

Soderstrom, TR., and C.E. Calderon 

Schuster. J. 

1909. 

Soderstrom, TR. 

1971, Insect Pollination in Tropical Rainforest Grasses. Biotropica, 

1974, Primitive Forest Grasses and Evolution of the Bambusoideae. 

3(1):1-6. 

Biotropica, 6(3):141-153. 

The Position of Bamboo Genera and Allies in a System of Grass 

Classification. In T.R. Soderstrom, K.W. Hilu, C.S. Campbell. and 

M.E. Barkworth, editors, Grass Systematics and Evolution, pages 

225-238. Washington, D.C.: Smithsonian Institution Press. [Proceedings of the International Symposium Held at the Smithsonian 

Institution, Washington, D.C., 27-31 July 1986.1 

Soderstrom, TR., and R.P. Ellis 

1987. 

Soderstrom, TR., R.P. Ellis, and E.J. Judziewicz 

1987. The Phareae and Streptogyneae (Poaceae) of Sri Lanka: A 

Morphological-Anatomical Study. Smithsonian Contributions to 

Botany, 65:l-27. 

A Morphological Study of Alvimia (Poaceae: Bambuseae), a New 

Brazilian Bamboo Genus with Fleshy Fruits. American JOIUM~ of 

Botany, 75:819-839, 17 figures. 

Soderstrom, T.R., and X. Londono 

1988. 

Soderstrom, TR., and F.O. Zuloaga 

1985. Diandrolyra iatianoe (Poaceae: Olyreae), a New Herbaceous 

Bamboo from Brazil. Brittonia, 37(1):1-5, 1 figure. 
NUMBER 68 51 

Stapf, 0. 

1898-1900. Gramineae. In W.T. Thiselton-Dyer, editor, Flora Capensis, 

7(24):310-391. London: Lovell Reeve and Company, Ltd. 

[1898:3 10-383; 1899:385-576; 1900~577-79 1.1 

Steudel, E.G. 

1855 [1853-18551. Synopsis Plantarm Glumacearm, Part 1: Synopsis 

Plantarum Glumacearm. 475 pages. Stuttgart: J.B. Metzler. 

[Published in 1853, but dated 1855. This book was published 

between 1853 and 1855: pages 1-80in 1853; pages 81-400 in 1854; 

pages 401-475 in 1855.1 

Tateoka, Tuguo 

1962. Starch Grains of Endosperm in Grass Systematics. Botanical 

Magazine (Tokyo), 75(892):377-383. 

Notes on Some Grasses, M: Systematic Significance of Bicellular 

Microhairs of Leaf Epidermis. Botanical Gazette (Chicago), 

121(2):8&91. 

Notes on Some Grasses, XM: Systematic Significance of Microhairs 

of Lodicule Epidermis. Botanical Magazine (Tokyo), 80(952):394- 

403. 

1961. Anatomy of the Monocotyledons, 11: Palmae. xiii + 345 pages, 18 

figures, 45 plates. Oxford: University Press. 

Les “oreillettes” des Graminks. Bulletin de la Sociefte‘ Botanique 

de France, 119(7-8):441-462. 

Tateoka, Tuguo, S. Inoue, and S. Kawano 

1959. 

Tateoka, Tuguo, and T Takagi 

1967. 

Tomlinson, P.B. 

Tran Van Nam, Mme. (Tran Thi Tuyet Hoa) 

1972. 

Trinius, C.B. 

1830. Graminum genera quaedem speciesque complures definitionibus 

novus. Memoires de L’Academie Imperiale des Sciences de St. 

Petersbourg, 6(1):54-93. 

Study on the Embryos of Sasa nipponica and Pleioblastus chino. 

Journal of Japanese Botany, 32:193-200. 

Los cromosomas de Sfreplocheta spicata Schrad. (Gramineae). 

Darwiniana, 12379-383. 

Principles of Dispersal in Higher Plants. Third edition, 215 pages. 

Berlin: Springer Verlag. 

Watson, L., H.T. Clifford, and M.J. Dallwitz 

The Classification of the Poaceae: Subfamilies and Supertribes. 

Awfralian JOWM~ of Botany, 33:433-484. 

Struktura endosperma i zarodysha zlakov kak sistematicheskii 

priznak. [Endosperm and Embryo Structure of Grasses as a 

Taxonomic Feature.] Akademiya Nauk SSSR, Trudy Botanischeskogo Institutu im. V.L. Komarova, seriya 7 (Morfologiya i 

Anatomiya Rastenii), [Transactions of the V.L. Kornarov Botanical 

Institute of the Academy of Sciences of the USSR, series 7 

(Morphology and Anatomy of Plants)] 1:121-218, 91 figures. 

[Unpublished English translation for the Smithsonian Institution and 

the National Science Foundation, Washington, D.C., 1975, in the 

files of the Hitchcock and Chase Library, Department of Botany, 

Smithsonian Institution.] 

Usui, H. 

1957. 

Valencia, J.I. 

1962. 

Van der Pijl, L. 

1982. 

1985. 

Yakovlev, M.S. 

1950. 
Index 

Olyreae Kunth, 1,22, 41, 46, 47, 48 

Olyrodae Soderstrom and Ellis, 48 

Oryza Linnaeus, 27, 46 

Oryzanae Watson, Clifford, and Dallwitz, 48 

Oryzeae Dumortier, 46,47,48 

Aechmea pineliana Brongniart, 4 

Alvimia Soderstrom and bndoiio, 28 

Anomochloa Brongniart, 1,2,22-29,44,46 

A. macranfoidea A. Brongniart ex Pritzel, 5 

A. marantoidea Brongniart, 37,46,47,48 

Anomochloeae C.E. Hubbard in Hutchinson, 46, 47, 48 

Anomochlooideae Pilger ex Potnal, 46 

Arberella Soderstrom and CalderQ, 22,28,39 

Bambusanae Watson, Clifford, and Dallwitz, 48 

Bambuseae Kunth, 1,47 

Bambusoideae Nees von Esenbeck, 1,22,46,47,48 

Buergersiochloa Pilger, 41 

Buergersioch1oeaeS.T Blake, 1,41,47,48 

Crypfochloa Swallen in Woodson and Schery, 22,28 

Dendrocalamus Nees von Esenbeck, 28 

D. membranaceus Munro, 28 

Diandrolyra Stapf, 3,46 

D. bicolor Stapf, 47 

Froesiochloa G.A. Black, 40 

Gigantochloa Kurz, 41 

Guadua Kunth, 46 

Guaduella Franchet, 1, 44 

Guaduelleae Soderstrom and Ellis, 1, 47 

Ichnanthus grandijolius Doell in Martius, 22 

Joinvillea Gaudichaud, 47 

Joinvilleaceae Tomlinson, 47 

Lepideilema Trinius, 34 

L. lancijoliwn Trinius, 34 

Leptarpis R. Brown, 28 

Lithache Palisot de Beauvois, 22,28 

Lygewn befling ex Linnaeus, 27,28 

Maclurolyra Calder6n and Soderstrom, 47 

Melica Linnaeus, 27 

Olyra Linnaeus, 3.28 

0. caudata Trinius, 28 

Q U.S. GOVERNMENT PRINTING OFFICE: 1989 - 20 2 -41 6/600 3 2 

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