Desmodium subsericeum Malme, Ark. Bot., Spec. Nov.
Creators: name: Lima, Laura Cristina Pires
name: Queiroz, Luciano Paganucci De
name: Tozzi, Ana Maria Goulart De Azevedo
name: Lewis, Gwilym Peter
Publisher: name: Zenodo
Year: 2014
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Magnoliopsida
Fabales
Fabaceae
Desmodium
Desmodium subsericeum

description: 28. Desmodium subsericeum Malme, Ark. Bot. 18(7): 4. 1922. Meibomia subsericea (Malme) Schindl., Repert. Spec. Nov. Regni Veg. 20: 145. 1924. Lectotype (designated here):— BRAZIL. Paraná: Capão Grande, 23 February 1910, P. Dusen s.n. (lectotype S!, isolectotypes BM![2 sheets], E!, G!, K!). Remaining syntypes: Brazil. Minas Gerais: Caldas, 23 February 1859, A.F. Regnell I: 89 (K!, S!); loco haudo indicato, J.F. Widgren s.n. (LE!, S!); São Paulo: Serra de Caracol, 18 March 1874, C.W.H. Mosen 1207 (S!). Fig. 30.   
 Meibomia malmei Schindl., Repert. Spec. Nov. Regni Veg. 20: 144. 1924. Lectotype (designated here):— BOLIVIA. Tarija, R.E. Fries 1163 (lectotype S!, isolectotype G!). Remaining syntypes: Bolivia. Tarija, K. Fiebrig 2274 (BM!, E!, G![2 sheets], GOET!, HBG!, K!, M!, P!, S!, U!, W!); Argentina. Jujuy: Rio Grande, Él Volcan ad. Fluv., Herb. F. Kurtz 11767, F. Claren s.n. (CORD*! S!).   
Prostrate, ascendent or decumbent, branched subshrub, lacking stolons rooting at the nodes, without a xylopodium; stems virgate, not slender, tetragonal, sulcate, sparsely or densely sericeous and uncinate, not glaucous; internodes 1.8–4.2 cm long. Stipules 2.5–5 × 1.5–2 mm, ovate, not auriculate, not amplexicaul, free from each other, apex acute, margin ciliate, glabrescent, veins conspicuous, caducous. Leaves trifoliolate; petiole 12–48 mm long, cylindrical, sulcate, sparsely or densely uncinate; rachis 4–12 mm long; stipels ca. 1 mm long, subulate, margin ciliate, sparsely or densely uncinate on the outer surface, caducous; leaflets discolorous, chartaceous, venation craspedodromous, primary and secondary veins prominent, tertiary veins flush with the abaxial surface, indumentum densely velutinous on the primary, secondary and tertiary veins on the abaxial surface, adaxial surface puberulous or sericeous, uncinate hairs covering both surfaces, terminal leaflet 4.5–6.2 × 3.4–3.8 cm, ovate or broadly elliptic, base oblique or obtuse, apex subacute, acuminate, mucronate, lateral leaflets 3.2–4 × 2.5–2.8 cm, the same shape as the terminal leaflet. Inflorescence a terminal or axillary pseudoraceme or paniculate; the main axis longer than the adjacent leaves, 15.5–25 cm long, sparsely or densely uncinate and tomentose, 2 flowers per node; primary bract 7–8.5 mm long, ovate, margin ciliate, puberulous-uncinate and tomentose on the outer surface,  
 84 • Phytotaxa 169 (1) © 2014 Magnolia Press   
 LIMA ET AL.   
caducous, veins slightly conspicuous on the outer surface; secondary bract 1.5–3 mm long, linear, margin ciliate, hirsute on the outer surface, caducous, veins inconspicuous on the outer surface; pedicel 7–10 mm long, sparsely or densely puberulous-uncinate and hispid. Flowers 8–11 mm long; calyx bilabiate, tube campanulate, 1.5–2 mm long, puberulous-uncinate and tomentose on the outer surface; upper lip bifid, broadly elliptic, the 2 teeth joined for ca. ¾ of their length, apex acute, ca. 0.5 mm long; lower lip trifid, lateral tooth lanceolate, 2–2.5 mm long, central tooth lanceolate, 3–3.5 mm long; corolla lilac, standard 7–8.5 × 5–7 mm, obovate, apex obtuse, maculate at the base, claw 1–2 mm long; wing petals 7–8.5 × 0.5–1 mm, oblong, apex obtuse, without callosities, claw 0.5–1 mm long; keel petals 7–9 × 2.5–3 mm, narrowly obovate, apex acute, with callosities, claw 2.5–3 mm long; androecium monadelphous, 8–11 mm long, vexillary stamen partially fused with the other from the base 3.5–4.5 mm long; ovary 3–5 mm long, villose, stipe 0.8–1.5 mm long, glabrous. Loment 2.3–4.2 cm long, stipe 1.5–2 mm long, uncinate, isthmus marginal, upper suture straight or arcuate, lower suture crenate; articles uniform 4–9, 3.5–5 × 2–3 mm, triangular or subtriangular, not tortuous, indehiscent, subcoriaceous, veins insconspicuous, densely uncinate. Seed ca. 2.7 × 1.2 mm, oblong, hilum central.  
 Selected specimens examined:— BRAZIL. Distrito Federal: Brasília: Ca. 3 km oeste, de Goiás, limite com Distrito Federal, 9 April 1976, fl., C . Davidse et al. 12161 (SP). Espírito Santo: Venda Nova: rodovia BR-262, viaduto Venda Nova, 6 December 1984, fl., fr., G . Hatschbach & J. M. Silva 48661 (MBM). Goiás: Caldas Novas: Beira do rio Corumbá, próximo ao eixo da barragem de Corumbá II, 30 April 1993, fl., fr., R . F. Vieira et al. 1505 (CEN). Minas Gerais: Viçosa: Trilha perto da estrada no km 378, 12 April 1930, fl., Y . Mexia 4606 (BM, G, K, U). Paraná: Rio Branco do Sul: rio Abaixo, 25 March 1975, fl., E . Ferreira 212 (MBM, SPF). Rio de Janeiro: Nova Friburgo: Pico Nova Caledônea, 14 January 1985, fl., fr., H . C. de Lima et al. 2522 (RB). Rio Grande do Sul: Machadinho: área abrangida pela UHE-Machadinho, 20 December 2008, fl., fr., L . C. P. Lima et al. 502 (HUEFS). Santa Catarina: Lauro Miller: rio do Meio, 20 March 1959, fl., R . Reitz & R. M. Klein 8681 (B, BR, G, K, L, M, PACA). São Paulo: Ribeirão Grande: Parque Estadual Intervales, trilha da Caçadinha, estrada do Carmo, 15 April 2003, fl., fr., A . C. Aguiar et al. 119 (ESA).   
 Distribution and Ecology:— South America in Argentina, Bolivia, Brazil, Peru, and Uruguay (Schubert 1945, Izaguirre & Beyhaut 1998, Vanni 2001, Lima et al. 2010). In Brazil D. subsericeum occurs in the Distrito Federal, and in the States of Espírito Santo, Goiás, Minas Gerais, Paraná, Rio de Janeiro, Rio Grande do Sul, Santa Catarina, and São Paulo, in areas of Rain Forest and in Cerrado associated with gallery riparian forests.   
 Conservation Assessment:— Least Concern ( LC), not endangered (IUCN 2001).   
 Phenology:— flowering and fruiting from November to July.   
 Etymology:— from the Latin sub (= somewhat) + sericeus (= sericeous), in reference to the subsericeous indumentum of the whole plant.   
 Common Name:— carrapichinho; carrapicho; carrapicho-de-boi; fava azul; fucinho-de-boi; marmelada-decavalo; pega-pega.   
 Taxonomic notes:— sulcate tetragonal stems, leaflets with a velutinous abaxial surface and craspedodromous venation, ovate bracts more than 7 mm long, and triangular or subtriangular articles are diagnostic characteristics of D. subsericeum.   
 Desmodium subsericeum is similar vegetatively to D. affine in leaflet shape and venation, as well as in habit, but it can be differentiated by sulcate, tetragonal stems (vs. striate, cylindrical in D. affine), caducous stipules (vs. persistent), bracts more than 7 mm long (vs. to 3 mm long in D. affine), and triangular articles (vs. oblong).   
 The shape of the primary bracts, flowers more than 7 mm long, and triangular articles are characteristics exhibited by D. subsericeum and D. uncinatum. These species are distinguished by the striate stems and the leaflets with brochidodromous venation in D. uncinatum. The specimens cited by Bentham (1859) as Desmodium uncinatum correspond to D. subsericeum. Hoehne (1921) cited specimen “ Paraná, Piraquara, P. Dusén 3259 (R!)” as Meibomia uncinata (Jacq.) Kuntze, but this collection is correctly identified as D. subsericeum.   
 Desmodium subsericeum is similar to D. intortum with its subshrub habit, sulcate stems, ovate-rhombic leaflets, flowers 8–11 mm long, and subtriangular to triangular articles. Azevedo (1981) cited D. intortum as a possible synonym of D. subsericeum. These species are not recognised as synonyms in this study because D. intortum possesses substantial phenotypic plasticity and wide geographic distribution. It also occupies different habitats, occuring in a subspontaneous manner in tropical Central and South America, and has been introduced into the Old World. On the contrary, D. subsericeum has a well-defined vegetative morphology and occurs on the border of riparian or gallery forest, or in the Atlantic forest formations of subtropical South America.   
 DESMODIUM (LEGUMINOSAE, PAPILIONOIDEAE) IN BRAZIL   
 Phytotaxa 169 (1) © 2014 Magnolia Press • 85 86 • Phytotaxa 169 (1) © 2014 Magnolia Press   
 LIMA ET AL.   
 Schindler (1924) established the name Meibomia malmei based on specimens cited by Malme (1922) as Desmodiumsubsericeum var.?. Burkart (1939) synonymised Meibomia malmei with D. subsericeum because any morphological differences between the two are superficial (e.g., density of indumentum on the stem, and leaflet length and texture). We follow Burkart`s synonymy.   
 The specimens of “P. Dusen s.n.” (S!) and “R.E. Fries 1163” (S!) were selected as lectotypes of D. subsericeum and Meibomia malmei, respectively, because they better concord with the information presented in the protologue.
description: Published as part of Lima, Laura Cristina Pires, Queiroz, Luciano Paganucci De, Tozzi, Ana Maria Goulart De Azevedo & Lewis, Gwilym Peter, 2014, A Taxonomic Revision of Desmodium (Leguminosae, Papilionoideae) in Brazil, pp. 1-119 in Phytotaxa 169 (1) on pages 84-87, DOI: 10.11646/phytotaxa.169.1.1, http://zenodo.org/record/10089817