425 

NOAA Technical Report NMFS Circular 425 

Marine Flora and Fauna of 

the Northeastern United States. 

Arthropoda: Cirripedia 

Victor A. Zullo 

April 1979 

u.s. DEPARTMENT OF COMMERCE 

National Oceanic and Atmospheric Administration 

National Marine Fisheries Service 
NOAA TECHNICAL REPORTS 

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NOAA Technical Report NMFS Circular 425 

Marine Flora and Fauna of 

the Northeastern United States. 

Arthropoda: Cirripedia 

Victor A. Zullo 

Apri l 1979 

u.s. DEPARTMENT OF COMMERCE 

Juan la tv' Kreps Secretar 

National Oceanic and Atmospheric Adm inistration 

R L r,ar" A Fran" A.c11"'"' n st a 

Terry L Leltze A.ssistan' Ad'T1 n s rator or s res 

National Marine Fisheries Service 
FOREWARD 

This issue of the "Circulars" is part of a subseries entitled "Marine Flora and Fauna of the 

Northeastern United States." This subseries will consist of original, illustrated, modern 

manuals on the identification, classification, and general biology of the estuarine and coastal 

marine plants and animals of the northeastern United States. Manuals will be published at irregular intervals on as many taxa of the region as there are peciaJists available to collaborate in 

their preparation. 

The manuals are an outgrowth of the widely used "Keys to Marine Invertebrate of the 

Woods Hole Region," edited by R. 1. Smith, published in 1964, and produced under the au pi ces 

of the Systematics-Ecology Program, Marine Biological Laboratory, Woods Hole, Mass. Instead of revising the "Woods Hole Keys," the staff of the Systematics-Ecology Program decided 

to expand the geographic coverage and bathymetric range and produce the keys in an entirely 

new set of expanded publications. 

The ":\larine Flora and Fauna of the ::.Iortheastern United States" is being prepared in collaboration with systematic specialists in the United States and abroad. Each manual will be 

based primarily on recent and ongoing revisionary systematic research and a fresh examination 

of the plants and animals. Each major taxon, treated in a separate manual, will include an in -

troduction, illustrated glossary, uniform originally illu trated keys, annotated checklist with 

information when available on distribution. habitat. life history. and related biology, reference 

to the major literature of the group, and a sy tematic index. 

These manuals are intended for use by biology students. biologists, biological ocea nographers, informed laymen. and others wishing to identit) coastal organisms for this region. In 

many instances the manuals will serve as a guide to additIOnal information about the species or 

the group. 

Geographic coverage of the ":\lanne Flora and Fauna of the ~ortheastern United State" i 

planned to include organisms from the headwaters of estuanes seaward to approxImately the 

:WO-m depth on the continental shelf from ~aine to \'irginia, but rna, vary somewhat with each 

major taxon and the interests of collaborators. Whenever possible representative specimens 

dealt WIth in the manuals will be deposited in the reference collections of major museum in the 

region. 

After a sufficient num bel' of manuals of related taxonomic groups have been pubJi hed. the 

manuals will be re\'ised, grouped, and issued as special volumes. These volumes will thus consist 

of compilatIOns ot indIvidual manuals within phyla such a the Coelenterata. Arthropoda, and 

fl.lollusca. or of groups of phyla. 
CONTENTS 

Page 

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

General biology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 

General characteristics .......................................... ................... 2 

Reproduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 

Development .... . ............ . ................................................... 2 

Adult arthropodal morphology ....................................................... 3 

Classification. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 

Order Acrothoracica ............................................................... : 3 

Order Apoda ............................................................ : . . . . . . . . . 3 

Order Ascothoracica . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 

Order Rhizocephala . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 

Order Thoracica . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 

l\Iorphology of Thoracica ................ .. ...... .. ..................................... 4 

Lepadomorpha, or "goose barnacles" .................................................. 4 

Balanomorpha, or "acorn barnacles" .................................................. 5 

Verrucomorpha, or asymmetric barnacles. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 

Study methods for Thoracica ..... . ................................. ,.................... 6 

Glossary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 

Key to thoracican Cirripedia of the northeastern coast of North America .. .............. ... .. ..... 9 

Annotated systematic list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 

Selected bibliography. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 

Systematic index. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 

Acknowledgments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 

Coordinating Editor's comments ......................................................... 29 

The National Marine Fisheries Service (NMFS) does not approve, recommend or endorse any proprietary product or proprietary material 

mentioned in this publication. No reference shall be made to NMFS, or 

to this publication furnished by NMFS, in any advertising or sales promotion which would indicate or imply that N:YIFS approves, recommends 

or endorses any proprietary product or proprietary material mentioned 

herein, or which has as its purpose an intent to cause directly or indirectly 

the advertised product to be used or purchased because of this NMFS 

publication. 

III 
Marine Flora and Fauna of the Northeastern 

United States. Arthropoda: Cirripedia 1 

VICTOR A. ZULL02 

ABSTRACT 

T his manual treats the estuarine and coastal marine barnacles of the northeastern Atlantic from 

the Gulf of St. Lawrence to Cape Hatteras, N.C. The introduction includes a review of the general 

biology, classifi cation, and diagnostic features of the five orders of Cirripedia, and an annotated ,pe- cies list covers those cirri peds reported from the region. The bulk of the manual is devoted to aid in 

the identification of barnacles (Order Thoracica), and includes an illustrated sy~tematic key to 

species augmented by a discussion and glossary of morphologic terms, and a guide to study method~ . 

INTRODUCTION 

The objectives of this manual are to provide the nonspecialist with a summary knowledge of Cirripedia and 

the means to locate and identify those species of barnacles encountered along the coast from the Gulf of St. 

Lawrence to Cape Hatteras, N.C. The barnacles of the 

Atlantic coast of North America have not been studied as 

a faunal unit and, as a consequence, most of the records 

of morphologic variation, ecology, and geographic distriution have come from scattered observations contributed by a number of investigators. The closest approach 

to a systematic survey was that of Pilsbry (1907, 1916) 

who monographed the American thoracican cirripeds 

based on museum collections. However, these early collections often were not representative either of the geographic area or of the range of environments in which individual species occur. 

Cirri peds are seldom adequately represented in faunal 

surveys, partly because they are adapted to a wide 

variety of habitats, of which many are likely to be overlooked by the casual observer. For example, the diminutive burrowing acrothoracican Trypetesa lampas is found 

only in the floor and sides of the interior of the body 

whorl of the shells of such gastropods as Lunatia heros 

and Polinices duplicatus, and only when these shells are 

inhabited by hermit crabs. Anyone who has seen a 

marine turtle has probably noticed large barnacles attached to its carapace, but the same turtle may be hosting two or three additional species of as many genera 

embedded in the gullet, flippers, and plastron. 

Another factor involves the difficulty of distinguishing cirriped taxa in the field. Many barnacles bear superficial resemblance to one another and cannot be 

separated without extended experience in identification 

or laboratory examination. Some species exhibit widely 

varying growth forms dependent upon such factors as 

Contribution :-"0. ,90 to '-lanne SCIences at the Cmversity of '\ortb 

Carolina at \\ilmlllg'ton. 

Department of Earth Sciences, Cniyersitv of :-':orth Carolina at Wil1l111l!!hltl. \\,ilmlllg'ton. ,C 2"403. 

crowding and substratum. Growth form were otten 

regarded as separate species in earlier surveys, thus multiplying the problems involved in the evaluation of past 

distributional records. 

This manual draws on data available in the literature 

and on personal field observation. Emphasis i placed on 

the "true" barnacles (Order Thoracica), which are the 

most commonly encountered cirripeds. Regional representatives of the Orders Acrothoraclca and Rhizocephala are included in the Annotated Sy tematic List 

and in the general discussion. 

Zoogeographic considerations. The cirriped fauna of 

the Atlantic coast is depauperate relative to tho e of 

other coastlines at similar latitudes, and is characterized by species having broad distributional range!>. In the 

area under consideration only nine balanomorph 

("acorn") barnacles of self-determined di tributlOn have 

been recognized, and only three of the e (33 0 are 

endemic to the western AtlantiC region. Within the arne 

latitudinal range on the Pacific coast of North America 

(lat. 35° to 50°", ) there are at lea t 19 pecie • of which 9 

(4To) are confined to the ea tern Pacific. 

The Atlantic coast has been divided mto four faunal 

provinces. These include a tropical province (Floridian) 

in southernmost Florida, a ubtropical pr vmce arolinian) north to Cape Hatteras, a warm temperate pro\'-

mce (Tran ition or Virginian) between ape Hattera 

and Cape Cod, Mass., and a cold temperate province 

(Boreal) north of Cape Cod. Thus in the area here conidered, two fauni tiC regions and a major pro\,ncial 

boundary are included. 

The m hore fauna can be divided convenientio,; into 

two part based on mode of di~tribution a r lated to 

habitat. The permanent tauna i. found in the relnon 

throughout the year and i dep ndent almo t entlTel on 

larval di persal for it: di. tribution. a the adul ttl 

primarily on fixed sub trata In the mter Idal nd ubtidal. The tran ient fauna, on the other hand, 0 cu onh 

;;eaonall\' (u~ually during the .ummer), and includ 

tho~e ~pecie. which normall' ettle on pela IC or mool 

object;. and or ani m. a::- adul • nd th r tor contmu 
the opportunity for dispersal throughout their adult life. 

The distribution of species in the permanent fauna is 

determined by the barnacle, whereas that of transient 

species is, at least during adult life, determined by the 

wanderings of the object to which it is attached. 

The significance of this difference in habitat as related 

to distribution can be seen readily in the following summary of the distribution of the total fauna: 

Geographic range 

Confined to northwest Atlantic 

Confined to North Atlantic 

Confined to Atlantic and Indian Oceans 

Confined to Northern Hemisphere 

Essentiallv worldwide 

Total fauna 

Permanent 

fauna 

4 

2 

1 

3 

o 

10 

Transient 

fauna 

o 

o 

o 

3 

15 

18 

The distinction between permanent and transient 

components of this fauna is not always clear cut. Some 

permanent species can be included among those barnacles notable as fouling organisms. Balanus ebumeus is 

native to the tropical and warm temperate shores of the 

western Atlantic, but has been introduced primarily by 

shipping to widely scattered parts of the world. 

Conversely, some fouling barnacles native to other 

regions occasionally are encountered in the northeast 

Atlantic. Balanus amphitrite amphitrite, spawned from 

parents attached to the hulls of vessels brought north 

from Florida, has been found living in the Cape Cod 

region in the fall months before temperatures dropped 

below adult survival limits. The tropical and subtropical species B. calidus and B. trigonus have been found 

on turtle barnacles attached to migrating turtles in the 

Cape Cod region. Also, a few species included in the transient fauna are capable of living on fixed objects. Lepas 

anatifera and Conchoderma virgatum are often found on 

sea buoys off the northeast Atlantic coast throughout the 

year. 

GENERAL BIOLOGY 

The following discussions are intended purely as an 

introduction to the Cirripedia. Those interested in a 

more comprehensive treatment of these subjects are 

referred to the chapter on Cirripedia by Newman et a1. 

(1969), on which much of the following is based. 

General Characteristics 

Cirripeds are unique among Crustacea in having taken 

on an exclusively sessile habit either as free-living filter 

feeders or as highly sp~lized parasites. They are 

m;;irine' alld estuarine organisms that are found at all 

depths of the oceans in a wide variety of habitats, but it 

is in the intertidal and on the shelf that the cirri peds 

have achieved their greatest development. Cirri peds are 

of such abundance along many shorelines that paleontologists of future times might well regard the present as 

the "Age of Barnacles." 

2 

In basic body plan cirripeds resemble Branchiura, 

Copepoda, and Mystacocarida, and have been included 

with these groups in the Maxillopoda of Dahl (1956). The 

maxillopod plan is obscured in most adult cirripeds by 

major body modifications related to a sessile existence, 

but it can be reconstructed from larval stages and from 

the adults of a few phylogenetically primitive species. 

Fundamentally, the cirriped body consists of: 1) a head 

region of five segments bearing (from the anterior end) 

first and second antennae, mandibles, and first and second maxillae; 2) a thorax of six segments, each bearing a 

pair of biramous appendages; and 3) a five-segment abdomen without appendages, except for a caudal furca on 

the last. The female genital openings are near the bases 

of the first thoracic appendages, whereas the male apertures are located on the first abdominal segment, or the 

last thoracic segment in those that have lost the abdomen. 

Reproduction 

Cirripedia are either separate sexed or hermaphroditic. In those with separate sexes the male is greatly 

reduced, consists of little more than reproductive structures, and is attached in or about the external aperture of 

a normal size female or hermaphrodite. In all cirripeds, 

eggs develop external to the body, but within the mantle 

cavity (body chamber) enclosmg the animals. Eggs are 

usually depo:lted in sheets (lamellae) on either side of 

the body near the base of the mantle cavity. perm from 

a neighboring hermaphrodite or attached male is introduced into the body chamber by means of an extensible, 

muscular intromittent organ or penis, which is located in 

the midlme immediately posterior to the thoracic limbs. 

Development 

The eggs develop into free swimming, feeding, 

nauplius larvae, which are released into the water 

column. In a few species some or all of the naupliar stages 

are passed within the mantle cavity. The nauplius is 

characterized by frontolateral horns on the dorsal shield 

(except in Ascothoracica), a single eye, uniramous first 

antennae, and biramous, natatory second antennae and 

mandibles. The nauplius passes through six increasingly 

complex stages of development. 

The sixth naupliar stage metamorphoses into a cyprid 

larva. The cyprid possesses a bivalved carapace derived 

from the naupliar dorsal shield, prehensile first antennae 

(the second antennae are lost), compound eyes in addition to the naupliar eye, and six pairs of biramous, 

natatory thoracic appendages. Although the cyprid differs markedly from the nauplius, its body plan is foreshadowed in the sixth naupliar stage, which bears compound cyprid eyes and six incipient thoracic segments. 

The cyprid is short lived and does not appear to feed. 

Mter a period of site selection, it attaches to the substratum by means of cement glands on the first antennae 

and metamorphoses into the adult stage. In most endoparasitic Rhizocephala the cyprid stage is succeeded by 
an interual kentrogen stage which, in turn, metamorphoses into the adult. The calcareous plates characteristic of the adult shell in Thoracica may appear before or 

after t he bivalved cyprid carapace is cast. 

Adult Arthropodal Morphology 

Modifications of the maxillopod body plan take several 

different forms in the various groups of cirripeds. The 

adult rhizocephalan cannot be distinguished as either a 

crustacean or an arthropod. It lacks appendages and a 

digestive tract, and consists primarily of ramified nutritive tissues and reproductive structures. Only through 

larval development can the cirriped relationships of the 

Rhizocephla be deduced. 

The remaining groups are much more conservative in 

their modifications, and their structural homologies are 

more easily recognized. Here the head segments are fused 

to form an enlarged sac (prosoma) bearing the head 

appendages and, in most, the first pair of thoracic appendages. The first antennae form the basis of attachment, 

the second antennae are absent, and the mandibles and 

the first and second maxillae are grouped together about 

the mouth and enclosed by the labrum or upper lip. 

Mandibular palps are found attached to the mandibles 

in Acrothoracica or to the lateral edges of the labrum in 

Thoracica. 

These mouth parts or trophi are located on the true 

ventral side of the cirriped adjacent to the thorax, and 

serve to gather food or to handle and reduce food passed 

to the mouth. In the parasitic Ascothoracica, the trophi 

are modified to form an oral cone for piercing and sucking. In the free living Acrothoracica and Thoracica, the 

trophi transfer and comminute food particles gathered 

by the thoracic appendages. 

In the parasitic Ascothoracica, the thoracic appendages are not involved in feeding and retain the natatory 

appearance of their cy prid homologs. Those of 

Acrothoracica and Thoracica, however, are used in food 

gathering and transfer and are much modified in form. 

These appendages, termed cirri, are characteristically 

t1attened laterally, curled anteriorly, bear fine setae, and 

increase in length posteriorly. The first one to three pairs 

of cirri are usually further modified as mouth appendages and can be recognized by their shorter length , lesser curvature, and stouter appearance. In Acrothoracica, 

only the first pair serve as mouth appendages. They are 

situated on the prosoma with the trophi and are well 

separated from the terminal grouping of feeding cirri. In 

Thoracica, the anterior one to three pairs of cirri may be 

m.odified as mouth appendages, and there is no noti ceable sepa ration between these and the feeding cirri, 

which are arranged in linear fashion rather than as a terminal grouping. Cha racteristically, the feeding cirri expand into a broad fan and sweep the water in a rhythmic 

motion for food particles that become entrapped in the 

setae. As the feeding cirri are retracted, the mouth cirri 

remove these particles and transfer them to the trophi. 

Posterior of the thoracic appendages, many 

Acrothoracica and some Thoracica bear a pair of caudal 

3 

appendages. These appendages may range in size from 

barely observable nubbins to long, lender, multiarticulate limbs. The function of caudal appendages i not 

known, but personal observations on the feeding 

behavior of the British barnacle Verruca straemia (MulIer) suggest that they aid in environmental sensing. 

Caudal appendages are homologous to the caudal furca 

of larval stages and of adult Ascothoracia . 

The function of the intromittent organ or penis located 

in the midline immediately posterior to the thoracic 

appendages has been discussed. The penis is muscular, 

capable of great extension, and annulate, but not segmented. Usually it bears a few setae often arranged in 

longitudinal rows and a denser tuft at its tip, but in some 

species more complex armature is present. Mention must 

a lso be made of the filamentary appendages characteristic of one group (Lepadomorpha) of Thoracica. These 

filaments are soft, rather fragile extensions of the body 

located at or near the bases of the first cirri. They have 

been considered to be of respiratory function , but are 

more probably involved in the formation of egg lamellae. 

CLASSIFICATION 

The Subclass Cirripedia of the Class Crustacea is 

divided into the following five Orders based primarily on 

adult life habit and form. 

Order Acrothoracica 

Acrothoracicans are unshelled, nonparasitic cirri peds 

having separate sexes. The females live in self-excavated burrows in the shells of mollusks, in coral skeleton , and in limestone, and have a full complement of 

trophi and from four to six pairs of cirri. The first pair of 

cirri is a lways associated with the trophi as a mouth 

appendage, and is separated from the posterior group of 

from three to five pairs of feeding cirri . Minute males are 

found near or about the aperture of the female, are without feeding structures, and appear to consist of little 

more than reproductive material. Both naupliar and 

cyprid larval stages are present. 

Order Apoda 

This order was created by Darwin (1854) for a single 

specImen of an enigmatic crustacean parasitic on the cirriped Heteralepas carnuta (Darwin) from the West Indies. This curious animal, named Pratea/epas bivincta 

Darwin, has not been reported since, but as indicated by 

;--";ewman et al. (1969), its morphology is equally suggestive of either a copepod or an epicaridean, and its assignment to the Cirripedia must be regarded as tentative. 

Order Ascothoracica 

The ascothoracicans, although highly specialized ectoand endoparasites of corals and echinoderms, retain 

many, presumably primitive features. Some have eparate sexes, but the majority are hermaphrodite . The 
adult body, can' ting of a pro oma. thorax, and abdomen, I hou ed in an uncalcified bivalved carapace. The 

pro oma bears prehen ile first antennae, a pair of filamen tou_ appendage that might repre ent the second 

antennae. and the trophi. which are modified to form an 

ural cone u .ed in ucking and piercing. The six pairs of 

blfamou, thoracic appendage are not involved in feedIDg nd retain a natatory appearance. The abdomen has 

fl\e egment _ The rna t anterior bears the penis, and the 

18: t a caudal furca. Both naupliar and cyprid larval 

tag-e~ are preent, but the nauplil differ from those of 

other cirri peds in lacking frontolateral horns on the doral hleld 

Order Rhizocephala 

The Rhizocephala are parasites of crustaceans, and 

(: artlcularly of decapods. Until recently rhizocephalans 

were thought to be wholly hermaphroditic, but a few 

pI.' Ie are now Known to have separate sexes. The adult 

I highly modified in bodv form and bears no resemblanc to other cirnpeds. The affinities of this group are 

l'xhlblted onlv hy the larval stages which include nauplii 

.... Ith charaden ·tic frontolateral horns (although lacking 

an hmentary canal) and a cyprid. In the majority of 

Pl'llf anut her larval stage, the kentrogen, composed of 

a rna of mesodermal cells surrounded by an ectodermal chitinous sac IS produced under the old cyprid 

c rapace. The kentrogen initiate penetration of the host 

ti ue" and is the precursor to the adult stage which conI t of internal nutritive structures and an external 

reprodUlti"e body. 

Order Thoracica 

Thi order encompasses the majority of cirripeds and 

includes the true barnacles. Thoracicans are 

predominantly free living or commensal forms which, as 

adults, live attached to a variety of substrata and are 

most notable for their development of external 

calcareous armature secreted by the carapace. Their life 

history and adult arthropodal morphology are similar to 

those described for Acrothoracica, but thoracicans differ 

in having a serial rather than grouped arrangement of the 

cirri, and in the association of the palps with the labrum 

rather than with the mandibles. In this regard 

acrothoracicans might be considered as modified 

thoracicans that seek protection by burrowing in calcareous substrata, rather than by secreting their own calcareous shell. Most thoracicans are hermaphroditic, but 

in some groups minute males are found in association 

with normal sized hermaphrodites or females. Although 

instances of self fertilization have been reported, cross 

fertilization, enhanced by the tendency of populations 

to be gregarious, is the rule. 

Ordinal characteristics are summarized in Table 1. 

MORPHOLOGY OF THORACICA 

Lepadomorpha, or "Goose Barnacles" 

The goose barnacle is divided into two parts: a fleshy, 

muscular stalk (peduncle), and a laterally flattened 

carapace (capitulum). The peduncle forms the attachTable I.-Summary of the general characteristics of the recognized orders of Cirripedia. 

Acrothoraclca Ascothoracica Rhizocephala Thoracica 

Larval .tages 6 nauplii 6 nauplii 6nauplii 6 nauplii 

without fronto- without alimenla teral horns tary canal 

cyprid cyprid cyprid cyprid 

kentrogen 

(in most) 

Adult 

Bod) prOBoma prosoma internal nutritive prosoma 

structures; 

thorax thorax external thorax 

reproductive body 

abdomen 

[ ruphi mouth parts for mouth parts formed none mouth parts for 

transfer and break- In to oral cone for transfer and breakup 

up oUood; palps piercing and of food; palps on 

on mandible. sucking labrum 

ThoracIc 4·6 pair. of clm 6 nonfeeding pairs. none 6 pairs of cirri used iii 

appenda e- u~d in food natatory food gathering 

gathenng In appearance 

rapace uncalcltied uncalclfied. none(?) armed with external 

bivalved calcified plates 

H.eprodUltl n eparate sexe moetly moetly many hermaphrohermaphroditic hermaphroditiC ditic. BOme separate 

sexed 

H bit fr~ lIV1n![K para81te of parasites of mostly free living and 

burro .... 'n In cnidanans and crustaceans commensals. attached 

calear WI echinoderm8 to various substrata 

ub !rata 
ment with. the substratum, is flexible to varying degrees, 

and , in some groups, is armed with spines or small calcareous plates. In all inshore lepadomorphs dealt with 

here, the peduncle is devoid of plates. The capitulum 

houses the body of the animal and usually bears external 

calcareous plates, whose number and arrangement are 

significant at the generic and, in some instances, at the 

specific level. 

The basic number of capitular plates in lepadomorphs 

appears to be five . A single elongate plate (carina) extends vertically along one edge as in the spine of a book. 

Two pairs of plates of dissimilar size and shape cover the 

flattened sides. The upper pair are the terga; the lower 

the scuta. The orifice is located on the edge opposite the 

carina and between the paired scuta and terga. An adductor muscle, connecting the scuta, regulates the 

opening and closing of the orifice. Among local lepadomorphs, Lepas and Trilasmis bear this basic complement of capitular plates. In Conchoderma, however, the 

plates are reduced or missing and do not cover the capitulum completely. 

The trophi of lepadomorphs include a large, tentlike 

labrum, and paired palps, mandibles, first maxillae, and 

second maxillae. The labrum is swollen (bullate) with a 

straight to gently concave cutting edge (crest) that may 

be lined with denticles or hairs (setae). The palps bear 

long, fine setae and are attached to the exterior-lateral 

margins of the labrum. The mandibles and maxillae are 

enclosed by the labrum. The pair of second maxillae are 

central in position and are flanked right and left by the 

paired first maxillae. The mandibles are situated between the first maxillae and the lateral margins of the 

labrum. The entire trophic complex stands above and 

surrounds the mouth. The shape and arrangement of 

teeth, denticles, and spines on the cutting edge of the 

mandibles, and the arrangement of spines and the shape 

of the cutting edge of the first maxillae appear to be 

related to feeding habits. These features have proven to 

be of systematic value at the generic and specific level. 

? 

U 

A 

PEDUNCLE 

5 

The first pair of biramous cirri are modified , at least 

slightly, as mouth appendages in all lepadomorphs. In 

most, both the first and second pairs serve as mouth 

appendages, with the first exhibiting a greater degree of 

modification than the second. 

Balanomorpha, or "Acorn Barnacles" 

Acorn barnacles differ basically from goose barnacles 

in lacking a peduncle. The balanomorph shell, which is 

homologous to the calcareous plated capitulum of the 

lepadomorph, is attached directly to the substratum. 

The shell is floored by membrane or by a calcareous disc 

(basis). The conical shell wall is formed primitively of 

eight plates, including a single rostrum and carina at 

either end and lateral pairs of rostrolaterals, laterals, and 

carinolaterals. The rostrum and carina are homologs of 

similarly named plates of lepadomorphs, and the laterals 

correspond to the rostral, median, and carinal latera of 

the basal whorl of plates in certain multiplated lepadomorphs. The paired terga and scuta (opercular plates) 

framing the aperture are removed from the plates of the 

shell wall and are arranged symmetrically within the 

dorsal orifice of the shell. The opercular plates are attached at their basal edges to an opercular membrane 

that extends across the dorsal orifice of the shell and is itself attached to the inner surface of the wall plates 

(sheath). Opening and closing of the aperture and movement of the opercular plates are effected by the adductor muscle connecting the scuta, and depressor muscles 

extending from the basal margins of the opercular plates 

to the base of the shell. 

The trophic complex is similar in arrangement to that 

of lepadomorphs. The labrum is bullate in Chthama100dea, weakly bullate in Coronuloidea, and non bullate 

with a median cleft in Balanoidea. Denticulation of the 

labrum, and the arrangement of denticles and spines on 

the cutting edges of the mandibles and first maxillae are 

useful systematic characteristics at the generic and 

specific level. 

B LATERAL 

Figure I.-External morphology: A. 

Lepadomorpha; B. Balanomorpha. 
articular 

furrow 

apex 

B 

articular 

furrow 

D 

apex 

spur 

baslcartnal 

angle 

Figure 2.-Marphology of opercular plates of Balanomorpha: A. (',,('rior or .cutum; B. ("tc ri or or 

tergum; C. interior of scutum; D. interior or tcrgum. 

In Chthamaloidea only the first and second cirri are 

modified as mouth appendages. In Coronuloidea the 

third cirrus is somewhat modified, and in Balanoidea the 

third cirrus is completely modified for use as a mouth appendage. 

Verrucomorpha, or Asymmetric Barnacles 

The shell of Verruca, the only extant verrucomorph 

genus, consists of four opercular plates, a rostrum, and a 

carina. Two of the opercular plates (paired tergum and 

scutum), together with the rostrum and carina, form an 

asymmetric, boxlike, rigid shell wall which is attached 

directly to the substratum. The other pair of opercular 

plates forms a movable lid to the box, occluding with the 

fixed pair in the shell wall. With rare exception the basis 

is membranous. The trophi and cirri are much like those 

of Lepadomorpha. With the exception of three species 

found in intertidal and subtidal waters, living verrucids 

are restricted to depths below the edge of the shelf. 

STUDY METHODS FOR THORACICA 

Barnacles are best preserved in 70-75 cc ethanol. Live 

specimens can be transferred directly to ethanol, but the 

preservative should be replaced in 24 to 48 h to offset 

dilution by body fluids. Fixing in Formalin or isopropyl is 

not recommended, because these preservatives harden 

the cuticle, making dissection difficult. Unbuffered For6 

malin softens or destroys calcareous parts. If Formalin is 

used, transfer the specimens to ethanol as soon as possible after thorough rinsing in water. 

In most cases, barnacles can be identified from shell 

and opercular plate morphology, but it also may be 

necessary to examine features of the trophi and cirri, and 

the body of the barnacle should be removed before disarticulation and cleaning of the calcareous parts are attempted. The body of a lepadomorph is readily removed 

with forceps by freeing the adductor muscle from the 

scuta at the base of the aperture and drawing the body 

out through the aperture. As an alternative , the cuticular membrane joining the scuta below the aperture and 

connecting the plates of the capitulum to the peduncle 

can be slit with a scalpel and the entire side of the capitulum laid back to expose the body. The body of balanomorphs and verrucomorphs either can be removed from 

the base (after chipping away the basis, if present), or 

can be lifted out of the orifice together with the opercular plates by cutting the opercular- membrane between the plates and the sheath. The body should be dissected under water. 

Most of the important taxonomic features of lepadomorphs can be observed without further preparation, 

however, many of the features of balanomorphs and 

verrucomorphs are internal, and adherent tissues must 

be removed. Calcareous parts are cleaned by soaking in 

commercial bleach (Clorox is recommended). Cleaning 

can be hastened without ill effect by warming the bleach 

up to 90°C. Once cleaned, the plates are rinsed 
cirrus 

A body chamber basis 

tergum 

sheath 

Figure a.-Internal morphology of Balanomorpha: A. cuta "a\ 

view of shell showing position and major features of body ; B. 

biramous thoracic appendage (cirrus); C. mandible; D. maxilla I; 

E. maxilla II; F. palp; G. labrum. 
thoroughly in water, dried, and placed in convenient containers. Curtin deep hole paleontological slide mounts 

are recommended for small opercular and compartmental plates. Replace the plastic cover slip with glass to 

reduce static electricity. 

Gross characteristics of the body, such as arrangement of appendages and number and placement of filamentary appendages, are examined in water under a dissecting microscope. If dissection is required, prepare a 

standard microscope slide (or two if the specimen IS 

large) either with glycerin jelly or a 3:1 mixture of Turtox 

media CMC-10 to CMC-S. The dissected parts can be 

transferred to these media directly from water. Use # 5 

jewelers forceps to remove appendages from either side of 

the body and place in sequence (cirri I through VI) on the 

slide. It .s convenient to arrange those of one SIde with 

the inner surface up, and the other with the outer surface 

up. The trophi are more difficult to dissect and will require some practice. The mouth parts can be steadIed by 

grasping the base of the labrum with forceps at its juncture with the prosoma. Remove the mandibles and the 

first maxillae by pulling them out from underneath the 

labrum. The basally fused second maxillae are removed 

together and teased apart on the slide. The palps may be 

left on the labrum, but they often obscure the labral 

crest. It is best to remove at least one palp for separate 

moun·mg. The labrum is cleaned of attached musculature before mounting. A cover slip completes the preparation, although permanency IS enhanced by nnging 

with clear nail polish. 

GLOSSARY 

adductor pit pit or depression on interior of scutum for 

attachment of adductor muscle; located between adductor ridge and occludent margin. 

adductor ridge ridge on interior of scutum between tergal margin and adductor pit. 

ala; plural, alae that part of the side of the compartmental plate, triangular in shape and delimited from 

the paries, which is overlapped by a part (radius) of 

the adjacent compartmental plate. 

aperture opening into body chamber between paired 

scuta. 

apex upper angle of either scutum or tergum. 

articles individual segments of the thoracic limbs. 

articular furrow furrow on tergal margin of scutum, or 

scutal margin of tergum forming part of the articulation between tergum and scutum. 

articular ridge ridge on tergal margin of scutum, or 

scutal margin of tergum, adjacent to articular furrow, 

and together with articular furrow forming articulation between tergum and scutum. 

basal margin lower margin of either scutum or tergum. 

basicarinal angle angle formed by intersection of basal 

and carinal margins of tergum. 

basioccludent angle angle formed by intersection of 

basal and occludent margins of scutum. 

basis membranous tissue or calcareous plate attached 

to substratum; forms floor of shell. 

8 

baslscutal anNle angle formed by intersection of basal 

and scutal margms of tergum . 

baslterNal anMle angle formed by intersection of basal 

and tergal margms of scutum . 

beak, or beakpd apf'X apex of tergum produced mto 

long, narrow pomt. 

body cham bf'r lllterior of shell containing body of 

animal. 

carina smgle compartmental plate at end of shell where 

cirri are protruded, or adjacent to terga; carina has 

alae only. 

cannal towards or adjacent to carina. 

carinal marMIn margin of tergum adjacent to canna , 

and occluding with carinal margin of opposing tergum 

carinolaterol., compartmental plates on either ide of 

carma, having radii on cannal ide and alae on ro tral 

side. 

Cirrus; plural, Clrn biramous thoracic appendage, of 

whIch there areix pairs in Thoracica. 

compartmental platf'8, or compartments rigid, articulated plates forming wall of hell. 

cre.\t" for depressor muscle.~ crest or groove on inte rior 

of terg-um near basicarinal angle for attachment of depressor muscles; cre5b may extend apically. 

fllamentar.\ appendages tapering filament of ti ue attached to ba e of one or more cirri, or to pro oma; 

believed to be of repiratory function. 

Inner lamina or lamella Inner hell layer of com· 

partmental plate separated from outer lamina by 

parietal tubes. 

labrum "upper lip" of trophi. 

laterals compartmental plate on ro tral Ide of the 

cannolateral , having radii on carinal ide and alae on 

ro tral Ide 

longitudinal or panetalepta wall of parietal tube, 

normal to and eparatmg Inner and outer lammae. 

mandible antenormost mouth appendage. 

maxilla I, or Inner maxtlla a mouth appendage et 

parallel with and po terior to mandible. 

maXilla II. or outer maxtlla "lower lip" of trophi, et on 

a po terior protuberance facing labrum . 

occludent margm margin on rostral side of scutum, and 

occluding with same margin on oppo ing scutum. 

opercular plates movable plates in orifice of shell, 

consisting of a pair of terga and a pair of scuta joined to 

the sheath by the opercular membrane. 

onftce dorsal opening of shell of balanomorphs and 

verrucomorphs; contains opercular plates. 

palp an oval, setose appendage; one attached to either 

side of upper margin of crest of labrum. 

paries; plural, parietes central, triangular part of compartmental plate, basal margin of which is attached to 

basis, and the sides of which are furnished with radii 

and/or alae . 

parietal septa see longitudinal septa. 

parietal tubes (also: parietal pores, longitudinal tubes 

or pores) longitudinal tubes in parietes formed by 

longitudinal septa separating inner and outer laminae 

of compartmental plate. 
I" dlilu I, Ill.! h' t Ik b t \ (n hI II and ub r turn an 

I~ pHdfllTlllrph . 

{HI llir lalvmi (itpn or mlJ ti" 

t 'r~fli lingle III tilt UIll /<Jf It 

pn'" or Illll (Il' 

IJfr)MJf)W I!lr~'·. !lc-hke b< eI\ 01 b mil I, 

lral) t" thoruclc IIrIlb III I Itl<)f1 01 "h 

r b I 

r I dl 

radIUs. plural. radII t hat part 01 t he Ie! 01 lflrnpnrtIT! 'ntal plul('~. delinllt·d lrom the pun iJ:-. a lh Ing 

in dir'ctlOl1 o[ growth and a eI pre.,,·d l' (nor lrlu(l', 

""hirh O\:erlap" alae "I adjat' 'nt compand nWlltu) 

plate". 

ramus; plural. rami each 01 the branchl' of l)lru!lll)ll~ 

thoracic limb". 

m,slral towllrcL or adjacent to th . ro:-.trum. 

f(),slral pialI' a compound 'ompartmental plat' at rl)~­

(ral end of "hell lorm d by apparent lu"jon of t\\{) or 

three compartmental plates. and bearmg radii on 

either side 

f(),lmla[('rals compartmental plate, ()n either, ide 01 

the ro:"trum, havlf1g radii both on carinal and ro tral 

Side" 

f()slrum compartmental plate at end o! . hell 0Ppo Ill' 

canna and adjac nt to :"cuta; bear" alae only. 

sculal mar#ln margin of tergum adjacent to scutum 

pi t 

ulUral 

II Ir 1111 to b 

01 (I'll 

Crop/II thl' mout h p r In lu 

rn til I', nd p Ip 

KEY TO THORACICAN C1RRIPEDI \ Of TilT· '-.OHTIIE \. 'I EH ('() \. 'J (11 

Attached to substratum by 11 shy peduncle 

tttllhed dln~L't1\' to.,u ) ... tratum; pl'dun ab nt 

I I ·ur.· I 

dornorph 

h\ n. It\ 

nlch r 

(I\tllf \\U Hil \ 

r I 
2(1) Calcareous plate (basis) covering base of shell (NOTE : this plate may be left on substratum 

when barnacle is removed) ....... . .... . . . .. . ... ... .... . . . .... ....... . ..... .... ............ 12 

Figure 6.-A. Balanus improvisus, cutaway view of 

shell showing underlying calcareous basis; B. Balanus crenatus, dorsal view of ca lcareous basis. Scale 

in millimeters. 

2(1) No basal plate; base of shell covered by membrane ............. . ...... . ..... .. ...... . . .. . ..... . 3 

3(2) Opercular plates filling dorsal orifice of shell; scutum and tergum articulated . .. .... .... .... ... . ... .4 

5 

Figure 7.-Chirona ham eri: dorsal view 

showing articulated oper cula r pla tes filling 

orifice. Scale in millimeters. 

3(2) Opercular plates greatly reduced or absent, not filling dorsal orifice; orifice closed primarily by 

membrane which may be greatly produced to form false "peduncle" above shell; tergum and 

scutum not articulated; barnacles attached to marine mammals, turtles, some fish and crabs 

........................... ........... .......... ........ .. ... . . . .. . . . Family Coronulidae 5 

10 

10 

Figure 8.-Chelonibia testudinaria : dorsal view of shell showing r educed . un a rticulated opercular plates tha t do not fill 

orifice. Sca le in millimeters. 
4(3) End plates of shell wall (carina and rostrum) overlapped by adjacent lateral plates; adult 

shell usually dark colored; found only in upper intertidal . .... . ........... . ...... Chthamalus fragilis 

R 

c 

;J/ ...... . ",", 

.~' 

.;. ..... : . 

. . .. r:... .. . . ;;.' 

., 

. . 

5 

Figure 9.- Chthamalus fragilis: A. diagram of compartmental plate arrangement 

(R = rostrum; C = carina); B. latera l view of shell with opercular plates; C. interior 

of scutum; Q. interior of tergum. Scale in millimeters. 

4(3) One end plate (carina) overlapped by adjacent laterals, the other (rostral plate) overlapping 

adjacent laterals; adults often in dense columnar masses; usually white; in middle and lower 

intertidal ................................ ...................... ... .... Semi balanus balanoides 

RP 

5 

E 

11 

Figure IO.-Semibalanus balanoides: A. diagram of 

compartmental plate arrangement (RP = rostral 

plate ; C = carina); B. lateral view of shell with 

opercular plates; C. exterior of scutum; D. exterior 

of tergum; E. interior of scutum; F. interior of 

tergum. 
5(3) 

5(3) 

Plates of wall when viewed from base septate between an inner lind lJutN wall 

Shell plates solid when viewed trom ba e ... 

5 

I q(lJrI' II (orfJ"Ulll daHl/emu. 

h",,,1 ,It·" ur I'lntt' 1,,'11 ""II 

Se.dl' In ,,"l1lnHql'r~ 

. . . .. ..... . ....... fj 

hgun' I~. P/lIl)I.·,>o hexlI 1)/0 ' ba,al ,it'" ur 

,otid ,hell ""11 ,hu\\ Ing midrib, . "('!ill' in millimeter,. 

6(5) Shell low conic or dome shaped; each plate WIth a conspicuou dO .... 'T1ward projecting. internal 

midrib ; found primarily on sea turtles in the North Atlantic ...... '.... . ..... '. Plat) lepa, hexa t) 10 

A 5 

Figure 13.-PlatylepaB hexastyloB: A. lateral 

view of shell and projecting midribs; B. dorsal view of shell. Scale in millimeters. 

5 

6(5) Shell not conic, without internal midribs ., .................................. , ..... ,., ........ 7 

12 
7(6) Shell small (2-8 mm), bowl shaped (orifice much larger than ba al opening): urfa e of hell 

ornamented by numerous, small, overlapping" cales"; embedded in oft, kIn or III throat of a 

turtles ...................... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . ...... , 'tomatoi"'pa I aru 

5 

Figure 14.-Stomatolepas elegans: lateral \i~" of 

shell with opercular plates showIng "M·al('~." S('ale 

in millimeler~. 

7(6) Shell small (less than 10 mm), star shaped; located at base of greatly expanded opercular membrane that resembles a fleshy peduncle; attached to cetaceans ................ X nobalanu..~ ~1()biClPltl., 

(5) 

Figure 15.-XenobalanU8 g/obicipiliB: A. 

complete specimen with star shaped hell 

at base; B. basal vie" of detached hell. 

Scale in millimeters. 

5 

Shell conic or of low dome shape; septa of wall thin, clo ely paced, unbranched, dent! ulate at 

basal edge; chamber housing body of barnacle cylindric (ba al opening a WIde or wider than 

orifice); on turtles or crab ................................................ h 

(5) Shell globose or conic; septa of wall thicker, widely paced. branchmg toward ... out r \\all n 

denticulate at basal edge; chamber hou ing barnacle body bowlhaped ba_alop mall r 

than orifice); on whales . . . . . . . . . . . . . . . . . . .. . ................... . 

a 

_________________________ 13~ __________________________________________ __ 
9(8) Shell globose, with distinctly rounded external ribs; barely embedded in whale skin ... Coronula diadema 

9(8) 

10(8) 

10(8) 

10 

Figure l6.- Coronula diadema: lateral view of shell 

(see Figure 8 also). Scale in millimeters. 

Shell low conic, with flat ribs; at least half of the shell embedded in whale skin ....... . Coronula regmae 

f Figure l7.-Coronula reginae : lateral view of shell. 

Scale in millimeters. 

Thickness of dome shaped shell wall at base greater than two-fifths basal diameter of shell; radii 

narrow or barely discernable, deeply sunken; orifice small, with greatest diameter less than onehalf of basal diameter; attached to sea turtles ................... ...................... ....... 11 

Thickness of shell wall at base much less than two-fifths of basal diameter of shell; radii broad, 

only slightly depressed; orifice large, with greatest diameter at least one-half of basal diameter; 

attached to crabs or Limulus ............................................. .. .. Chelonibia patula 

B 

Figure l8.-Chelonibia patula: A. shell with opercular plates; B. diagram of base of s hell 

wall. Scale in millimeters. 

14 
11(10) Radii usually transversely notched; spaces between septa of wall not filled with shell material 

(NOTE: spaces will be filled with tissue which can be removed with bleach); on surface of sea 

turtle carapace .......... . .. ....... . ....... ...... . ........... . .... ... .. Chelonibia te tudmarLa 

10 

Figure 19.-Chelonibia testudinaria: A. dorsal view of s hell with opercular plates showing notched radii; B. diagram of base of shell wall. Scale in millimeters. 

11(10) Radii absent or very narrow, not notched; cavities between septa filled nearly to base with shell 

material; usually partially embedded in turtle carapace . . ........................ Chelonibia caretta 

10 

Figure 20.-Chelonibia caretta: dorsal 

view of shell with opercular plates. Scale 

in millimeters. 

12(2) Plates of shell wall, when viewed from base, septate between an inner and outer wall, forming a 

5 

single row of longitudinal tubes .... ........ . ................ ... ........... ....... Balanidae 13 

Figure 2 I.- Balanus eburneus: basal view of lateral 

compartmental plate showing septate shell wall and 

parietal tubes. Scale in millimeters. 

12(2) Plates of shell wall solid when viewed from base ....... ................ . ........... Chlrona hamer! 

15 
1 c 

A 

B 

Figure 22.-Chirona hameri: A. basal view of internally ribbed, but solid lateral compartmental plate; B. lateral view of shell with 

opercular plates; C. exterior of scutum; D. exterior of tergum; E. interior of scutum; F. interior of tergum. Scale in millimeters. 

13(12) Exterior of scutum lacking distinct longitudinal striae or rows of pits ..... ..... .. ...... . ........ .. 17 

13(12) Exterior of scutum distinctly striate longitudinally, or with one or more longitudinal rows of 

pits ...................... ... .... ............... . .............. ..... ... ....... ........ . 14 

14(13) Scutum with one or more rows of pits; shell wall red and white striped; orifice triangular Balanus trigonus 

A 

B 

16 

Figure 23.-Balanus trigonus: A. dorsal view of 

shell and triangular orifice; B. exterior of scutum; C. exterior of tergum; D . interior of 

scutum; E. interior of tergum. Scale in millimeters. 
c 

o 

14(13) Scutum with distinct longitudinal striae; shell white; orifice diamond shaped .. . ... ..... ........... 15 

15(14) Ribs at base of interior of shell wall more numerous than septa; basal plate solid; shell with 

15(14) 

several strong, sharp ribs ...................................................... Balanus balanus 

B 

Figure 24.-Balanus balanus: A. basal view of compartmental platl" ,ho"-

ing internal ribs and septa; B. lateral view of ribbed shell; C. e"tenor of 

scutum; D. exterior of tergum; E. interior of scutum: F. interior of 

tergum. Scale in millimeters. 

Ribs at base of interior of shell wall all continuous with septa; basis porou (see Fig. 1 

17 
16(15) Shell wall smooth; carinal side of basal margin of tergum deeply excavated ........... Balanus eburneus 

Figure 25.-Balanus eburneus: A. 

lateral view of shell; B. exterior of 

scutum; C. exterior of large, worn 

tergum; D . interior of scutum; E. 

interior of tergum. Scale in millimeters. 

16(15) Shell wall plicate or with low, broadly rounded ribs; carinal side of basal margin entire .. Balanus calidus 

A 

c 

Figure 26.-Balanus calidus: A. latera l view of shell; B. exterior of scutum; 

C. interior of scutum; D. interior of tergum. Scale in millimeters. 

18 
17(13) 

A 

Adductor ridge of scutum absent; radii usually narrow ....... . .................... Balanus crenatus 

B 

c 

Figure 27.- Balanus crenatus: A. lateral view of shell; 

B. exterior of scutum; C. exterior of tergum; D. interior of scutum; E. interior of tergum. Scale in millimeters. 

17(13) Adductor ridge of scutum well developed ..... . .. . ... .... . ................................... 18 

18(17) Tergal spur narrow, less than one-fourth width of basal margin; radii narrow, not extending to 

parietes of adjacent shell plate; usually found in waters of low salinity ............. Balanus improvisus 

Figure 28.-Balanus improvisus: A. lateral view of shell with narrow radii; B. exterior of tergum; C. interior of scutum; D. interior of tergum. Scale in millimeters. 

18(17) Tergal spur broader, at least one-fourth width of basal margin; radii narrow to broad .. ............. 19 

19 
19(18) 

A 

Shell usually white, without definite color pattern or color stripes; tergal spur about one-third 

width of basal margin and placed about two-fifths its own width from basiscutal angle; radii narrow in conic, wide in subcylindric specimens ... . .................. . ... ... ..... Balanus subalbidus 

B 

o E 

Figure 29.-Balanus 8ubalbidus: . dorsa l view of shell ; B. exterior of scutum; 

C. exterior of tergum ; D. interior of 

~cutum; E. interior of tergum. 

19(18) Exterior of shell with gray, purple, or reddish longitudinal stripes; tergal spur narrower, onefourth to one-third width of basal margm . . . . . . . . . . . . . . . . .. . ......... ....... ....... ......... 20 

20(19) Exterior of shell with narrow, regularly spaced, gray to purple longitudinal stripe ; tergal spur 

less than one-half its own width from basiscutal angle; labrum with no more than three teeth on 

A 

either side of central cleft; lowermost intertidal and subtidal ................. .. .... Balanus venustus 

F 

lj 

Figure 30.-Balanus venustus: A. lateral view of shell; 

B. exterior of scutum; C. exterior of tergum; D . interior 

of scutum; E. interior of tergum; F. labrum. Scale in 

millimeters. 

20(19) Exterior of shell with broad, irregularly spaced, red-purple stripes, except on central areas of 

larger plates which are free of striping, leaving a broad, white band; tergal spur more than onehalf its own width from basiscutal angle; labrum multidenticulate within and on either side of 

central cleft; usually midintertidal ........... ... ....... .... ... ..... . Balanus amphitrite amphitrite 

20 
F 

Figure 3 I.-Balanus amphitrite amphitrite: A. lateral view of shell; B. exterior of scutum; C. exterior of tergum; D. interior of scutum; E. interior of tergum; F. labrum. Scale in millimeters. 

21(1) No calcareous plates present on capitulum; attached to cetaceans (NOTE: this is not a lepadomorph barnacle. The apparent "peduncle" is a prolongation of the opercular membrane extending out of a minute, star-shaped shell at its base. The shell is embedded in the skin of the cetacean and may be lost on removal of the barnacle. See Figure 12) ............. Xenobalanus globicipitis 

21(1) Calcareous plates present on capitulum ................. .. ................... ................ 22 

22(21) Five calcareous plates on capitulum; plates in contact or separated by narrow interspaces . ... .... .... 23 

22(21) Two to five small, widely separated plates on capitulum ................... ........ .... ........ 28 

23(22) Carina not extending upward between tergal plates; shell in profile slightly skewed; on lobsters 

and crabs from deeper water ........................ .. .......... ........ Trilasmis inaequilaterale 

A B 

Figure 32.-TrilasmUi inaequilaterale: A. 

lateral view showing placement of carina; 

B. apertural view showing curvature of 

capitulum. Scale in millimeters. 

23(22) Carina extending upwards between tergal plates; shell not noticeably skewed in profile ......... ..... 24 

21 
24(23) Carina angulate, terminating below in a flat, oblong disc; plates thin, papery, slightly separated 

....................................................................... . IJosima fascLcularis 

A 

Figure 3.1. D08ima faHcicularis: A. carina; B. lateral vie" of capitulum showing angulation of carina. Scale in millimeter" 

24(23) Carina evenly arched, terminating below in a fork; plates well calcified " ... " ..... , ... , ... Lepas 2.5 

Figure :)1. Carina of Lepas ~p, 

Scale in mill,meter,. 

25(24) Plates radially furrowed or strongly striate .......... , ..... , ................. , .. , ... , ......... 26 

25(24) Plates smooth or minutely stnate; may have one or more rows of browlll h square 

spots diagonally across scutum and, rarely, across tergum ...... ,. .., .... , .......... ,.,' . , .... '27 

26(25) Occludent margin of scutum strongly arched; shelf between occludent margin and ridge from 

apex to basal margin broad; 5-6 filamentary appendages on either ide of body at ba e of first 

thoracic limb .................................................... " .... , .... Lepas ansenfera 

Figure 35.-Lepas anserifera: lateral view of capitulum. Scale in 

millimeters. 

26(25) Occludent margin of scutum evenly curved; shelf between occludent margin and ridge narrow; 

0-2 filamentary appendages on either side of body at base of first thoracic limb .. ,.,". Lepas pectinata 

22 

Figure 36.-Lepas pectinata: lateral view of capitulum. Scale in 

millimeters. 
27(25) One or two filamentary appendages on either side of body at base of first thoracic limb; often 

with diagonal row of spots on scuta ....... ' .......................... . ..... . ..... . Lepas anatifera 

Figure 37.-Lepas anatifera lateral view of capitulum showing 

rows of spots on scutum. Scale in 

millimeters. 

27(25) Three filamentary appendages; upper part of peduncle orange in live specimens ..... .. ...... Lepas hilli 

5 

A B 

Figure 38.-Lepas hilli: A. latera l view of capitulum; 

B. cutaway of capitulum showing body with three 

filamentary appendages at base of first thoracic 

limb. Scale in millimeters. 

28(22) Body traversed by dark longitudinal bands; calcareous plates small, but well developed .... 

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Conchoderma uirgatum 

Figure 39.-Concholkrma virgatum: 

lateral view. Scale in millimeters. 

28(22) Body not banded; terga and carina greatly reduced, sometimes absent in adults; a pair of large, 

tubular "ears" rising above capitulum behind terga . ..... . ........ . . ... . ... .. . Conchoderma auritum 

23 
ANNOTATED SYSTEMATIC LIST 

This check list is arranged in a systematic hierarchy 

from class to family level. Genera are listed alphabetically within families and species within genera. 1 otes on 

distribution, habitat, and general occurrence are included with each listing. References in parentheses at the 

end of each listing are to publications of local importance. The classification of the Suborder Balanomorpha 

follows the recent revision of Newman and Ross (1976). 

Cross references to traditionally employed generic and 

specific names are provided in the Systematic Index. 

Class CRUSTACEA 

Subclass CIRRIPEDIA 

Order RHIZOCEPHALA 

Suborder KENTROGONIDA 

Family PELTOGASTRIDAE 

Peltogaster naushonensis Reinhard 1946. Vineyard 

Sound, Cape Cod, Mass.; on Pagurus annulipes 

Stimpson. 3-15 m (Reinhard 1946). 

Peltogaster paguri Rathke 1843. (?)Labrador; Newfoundland to Cape Cod, Mass.; western North Atlantic; 

North Pacific; on Pagurus pubescens Kr~yer. Intertidal to 157 m (Reinhard 1946). 

Family SACCULINIDAE 

Loxothylacus panopaei (Gissler 1884). York River, 

Chesapeake Bay, Va., on Eurypanopeus depressus 

(Smith); Caribbean Sea; Gulf of Mexico; (?)southern 

California; British Columbia. Intertidal to 250 m (Van 

Engel et al. 1966). 

Family CLISTOSACCIDAE 

Clistosaccus paguri (Lilljeborg 1861). Off Newfoundland and Nova Scotia (Grand Banks) on Pagurus 

pubescens Kr~yer, in 64-66 m; Nort h Atlantic; Bering 

Sea; Pacific coast of Alaska (Boschma 1928, Reinhard 

1946). 

24 

Figure Hl.-Cortchoderma auritum: 

lateral \ ie~ sho",ing "ea rs." Scale 

in millimeters. 

Family SYLONIDAE 

.'l,Lun h.\ppulytes Sar 1870. Off Halifax, ~ova cotia, on 

!:Jplruntucanl) I)ptnUS (Sowerby); :\'orth Atlantic and 

northea·t Pacific coast of ~orth America (Eo chma 

192tl) . 

Order ACROTHORACICA 

Suborder APYGOPHORA 

Family TRYPETESIDAE 

Trypetel)a Lampal) (Hancock 1 49). Gulf of t. Lawrence 

to :\'orth Carolina, burrow of females in floor and 

side of Intenor of body whorl of shell of Lunatia heros 

(Say), PoLinLcel) dupltcatus ('ay), and Buccinum undatum Linnaeu inhabited by the hermit crabs 

Pagurus pollicans ay and P. longicarpus ay; western Sweden to Roscof!, France; Mediterranean. Inner 

and outer shelf region (Tomlinson 1969; Wei bord 

1975). 

Order THORACICA 

Suborder LEPADOMORPHA 

Family LEP ADIDAE 

Conchoderma auritum (Linnaeus 1767). Cosmopolitan ; 

attached to whale barnacles and occasionally to ships. 

Open surface waters (Pilsbry 1907). 

Conchoderma uirgatum (Spengler 1790). Cosmopolitan; 

on ships, offshore buoys, and fish; common in clusters 

attached to the copepod Penella that is parasitic on 

the sunfish Mala mala (Linnaeus) (Pilsbry 1907). 

Dosima fascicularis (Ellis and Solander 1786). Cosmopolitan; on floating seaweed and driftwood in open 

water; found throughout the summer months in inshore waters (Pilsbry 1907). 

Lepas anatifera Linnaeus 1758. Cosmopolitan; attached 

to floating seaweed and driftwood in open water; common inshore and on beaches during July and August 

(Pilsbry 1907). 

Lepas anserifera Linnaeus 1767. Cosmopolitan; attached 

to floating sargassum weed and driftwood and 
occasionally on whales in open water; rno t abundant 

in Gulf Stream waters (Pilsbry 1907). 

Lepas hilli (Leach 1818). North Atlantic and North 

Pacific on Hoating debris; rare inshore (Pilsbry 1907). 

Lepas pectinato. Spengler 1793. Probably cosmopolitan; 

on noating seaweed and driftwood; appears in mid-

.J uly inshore (Pilsbry 1907). 

Family POECILASMATIDAE 

Trilasmis (Poecilasma) inaequiloterale (Pilsbry 1907). 

Attached to crustacean carapaces, especially those of 

geryonid crabs and Homarus. Occurs mainly at slope 

depths (Pilsbry 1907). 

Suborder BALANOMORPHA 

Superfamily CHTHAMALOIDEA 

Family CHTHAMALIDAE 

Subfamily CHTHAMALINAE 

Chlhamalus fragilis Darwin 1854. Cape Cod, Mass., 

south to the West Indies. On hard substrata in the upper third of the intertidal zone (Pilsbry 1916). 

Superfamily CORONULOIDEA 

Family CORONULIDAE 

Subfamily CHELONIBIINAE 

Chelunibia caretta (Spengler 1790). Found on carapaces 

of loggerhead and green turtles in tropical and temperate seas. Reported as far north as Cape Cod, Mass., 

on loggerheads (Zullo 1963; Zullo and Bleakney 1966). 

Chelunibia patula (Ranzani 1818). Worldwide in warmer 

seas on crustacean carapaces; commonly on Callinectes sapidus Rathbun and Limulus polyphemus 

(Linnaeus) on the southeastern and gulf coasts of the 

United States; occasionally on aged female Callinectes in Chesapeake Bay (Van Engel 1972). 

Chelunibia testudinaria (Linnaeus 1758). Worldwide in 

warmer seas on carapaces of marine turtles. Reported 

as far north as Newport, R.I., on a loggerhead (Pilsbry 

1916). 

Subfamily PLATYLEP ADIN AE 

Platylepas hexa '(vios (Fabriciu 1798). Worldwide in 

tropical and warm temperate seas on turtles, 

manatees, dugongs, and the gar Lepisosteus. Reported 

from loggerhead turtles from Delaware Bay, N.J. (Pilsbry 1916) and Cape Cod, ;\la s. (Zullo and Bleakney 

1966). 

Subfamily CORONl,lLINAE 

Coronula diadema (Linnaeus 1,6,), and 

Corunula reginae Darwin 1 5-l. The two specie of 

Curunula found in the North Atlantic occur primarily 

on the humpba k whale, but are known al 0 from 

:;perm and fin back whales. They attach primarily to 

the underlip, throat, lin. , and nu e . (orO/lUla r( ma 

i" otten a. "ociated \\ith C dwdf!ma, but 1 r r r nd 

more deeply em bedded in the kll1 \ Pil bn 1 1 ') 

_"tumotolepa, d(/~aTl' ICo ta 1,-3 ). \\ orld\\Id 10 

warmer "ea", embedded in the "oft . km nd ttlro t 01 

marine turtles. Reported a" lar north u 

on leatherbacb (Zullo and Hlenkne) 1 

XClwbalanu., Mlublup I" teen. trup 1 ,j} I>\n u\\n frum 

the :\orth and South Atlantic, .\Iecilterranl'an, ll1d 

South PaCIfic on L'a'll1g and hnback \\hllle ... .Ind purpoi::.e::.. Reported from the nipper ot the ('a 'Ing \\ hale, 

Glubwcephala intermedia, landed at • orth () nm 

and Wood" Hole, ;\la::.. (Pil"bry 1 ~1 Ill. 

Superfamily BALANOIDE \ 

Family ARCHAEOBALA'\'(D \E 

Subfamily ARCHAEOBAL\'\' 1,\ \E 

Chtnma hamert (Ascaniu~ 1,6,). :\orth Atlantic O( 'an, 

frum depth~ between 29 and ,3US m. :\\o"t abundant at 

depths bet ween .5.5 and 100 m on the ~hell" 01 large 

mollu:;k;;, such as J>lacupecten maRellallllU. (C;rnelinl. 

This is the largest :\orth AtlantiC barnacle, achie\ IT1g n 

height of 6, mm and a ba::.a! diameter of 6 mm. It ha~ 

been reported as far south as Chesapeake Bay (Pt!, br 

1916). 

Subfamily SE:vIIBALA:\'"J'\' \E 

0emibaianus balanoides (Lmnaeus 1,6,). Horeo-arl t it' 

regions of the Atlantic and Pacific Ocean . Fuund 

::.outh to Cape Hatteras, '\. C , in the middle and !mH-r 

intertidal zone. Thi::. I::' the rno~t commonl) encountered mtertidal barnacle along the northea t m 

Atlantic coat (Pilsbry 1916). 

Family BALA:\TIDAE 

Balanus amphitrtte amphitrite Darwm 1.54 0 mo· 

politan in tropical to warm temperate :-ea .. Hcproduc.-

ti\'e populatlUns along the Atlantic c )8. t of • orth 

America occur primarily in the middle and hmer Il1tertidal Zllne and appear to be restncted to regIOn outh 

of Cape Hatteras, ;-':.C. Rare indl\'ldual. pa .... ned 

from hip borne foulmg populallon ... can b found dur 

ing summer months north to l ape (od, . It! Thl 

~ubl:>pecles hal:> been conlu"ed \\ith R t lu ttl [Jam n 

(Henry 19,3; Henr\' and ;\IcLau hun Uri,"), Zull 

19(6). 

Balanus balanll~ lLinnaeul:> 175 . Arctl , 

and ~orth AtlantiC Ocean., .outh to 

Sound on the AtlantiC toa"t of . orth menc.a 

ll! Cape Cod, :\Ia~"., thi" pe Ie ran~e, up .... rd 

the lu \er third of the intertidal zone but t th 

it II:> re"tricted to .ubmer ed mner h II d pth 

br! 19161. 

Halmlll calrdu, Pibbr.\ 1 1 . Repr u t1H pop 

are not tound north ot l ap Hatter 

iona! II\€ indl\"idu I ... ha\C b n b n n 
mens of Chelonibia and Platylepas attached to marine 

turtles taken off Cape Cod, Mass. (Pilsbry 1916; Zullo 

and Bleakney 1966). 

Balanus crenatus Bruguiere 1789. This species has a 

distribution similar to that of B. balanus, with which it 

is often associated (Pilsbry 1916). 

Balanus eburneus Gould 1841. Natural distribution includes the Atlantic coast of the United States south of 

Salem, Mass., the Caribbean Sea, the Gulf of Mexico, 

and the northeastern coast of South America . In addition this species has been introduced to various parts 

of the Pacific Ocean, and the Mediterranean and 

Black Seas. Balanus eburneus is a euryhaline species, 

but north of Cape Hatteras, N.C., it predominates in 

the middle intertidal to immediate subtidal zones of 

estuaries. The species is rarely encountered in areas 

of normal marine salinities in this region, probably 

because of competition with the more successful 

Semibalanus balanoides (Henry and McLaughlin 

1975; Zullo et al. 1972). 

Belanus improvisus Darwin 1854. Apparently worldwide 

in tropical and temperate seas. Some of its present distribution can be attributed to introduction by man. 

This species occurs predominantly in estuaries in association with B. eburneus. It tolerates lower salinities 

than B. eburneus, but is generally less abundant 

(Henry and McLaughlin 1975; Carlton and Zullo 

1969). 

Balanus subalbidus Henry 1973. Ranges from Massachusetts south into the Gulf of Mexico. Often associated with B. improvisus with which it may be confused (Henry 1973; Henry and McLaughlin 1975). 

Balanus trigonus Darwin 1854. Worldwide in tropical 

and warm temperate seas. Reproductive populations 

are restricted to regions south of Cape Hatteras, N.C., 

but rare individuals have been found on specimens of 

Chelonibia and Platylepas attached to marine turtles 

taken as far north as Cape Cod, Mass. (Pilsbry 1916; 

Zullo and Bleakney 1966). 

Balanus venustus Darwin 1854. Worldwide, except eastern Pacific, in tropical and warm temperate seas; on 

the Atlantic coasts of the Americas from Cape Cod, 

Mass., south to Brazil. Ranges vertically from the 

lowermost intertidal through the inner shelf. This is 

the most common subtidal barnacle of the Virginian 

province, and has often been confused with B. 

amphitrite amphitrite. The color variants (described 

as subspecies) B. v. modestus, B. v. niveus, and B. v. 

obscurus do not warrant separation (Henry and 

McLaughlin 1975; Pilsry 1916; Zullo 1966). 

26 

SELECTED BIBLIOGRAPHY 

BOSCHMA, H . 

1928. Rhizocephala. Dan. Ingolf-Exped. 3(10), 52 p. 

CARLTON, J. T., and V. A. ZULLO. 

1969. Early records of the barnacle Balanu.9 ImprOU/.8u.9 Darwi

from the Pacific Coast of North America. Occas. Pap. Calif

Acad. Sci. 75, 6 p. 

DAHL, E. 

1956. Some crustacean relatIOnships. Hanstrom Festschrift

Lund Umv., Lund, p . 138-147. 

DARWIN, C. 

1854. A monograph on the sub-class Clmpedia, With figures of al

the species. The Balamdae, (or sessile clmpedes); the Verru

cidae Ray oc., Lond., 684 p. 

HE RY, D. P. 

1973. DeSCriptIOns of four new species of the Balanu.9 amphltnte

complex (Cirripedia, Thoracica). Bull. Mar. Sci . 23:964-1001. 

HENRY, D. P, and P A. McLA GHU~. 

1975. The barnacle of the Balanu.9 amphltnte complex (Cim

pedla, Thoraclca) Zool Verh. (Lelden) 141, 254 p. 

NEWMAN, W. A., and A. RO S. 

1976. Ren Ion of the balanomorph barnacles, including a catalo

of the species. ~an Diego ~oc. , at. Hlst. Mem. 9, 10 P 

;:";EW~IA:-" W A, V A ZCLLO, and T. H WITHERS. 

1969. Cimpedia. In R C Moore (editor), Treatise on mverte

brate paleontology, Part R Arthropoda 4.R206-R295 Geo!. oc

Am. and Univ Kansas. 

PIL BRi:', H. A. 

1907 The barnacles (Clrrlpedia) contamed in the collections of th

C .. '\'atlOnal ;vlu eum. U .. :--iatl. Mus. Bull. GO, 122 p. 

1916. The se slle barnacle (Cimpedla) contained In the collec

tion of the U '. :-'atlOnal ;vluseum, mcluding a monograph of th

American. pecies. U. . :--iatl. Mus. Bull 93, 366 p. 

REINHARD. E. G. 

1946. Rhizocephala from :--iew England and the Grand Banks. J

Wa h. Acad SCL 36:12,-131. 

TOMUNSO:-"-, J. T 

1969 The burrowing barnacles (Cirripedia: Orde

Acrothoracica). U. '. :-"-atl. Mus. Bull. 296, 162 p. 

Vftu"l ENGEL, W. A. 

1972. ubclas Cimpedia. In M. L. Wass (editor), A check list 0 

the biota of lower Chesapeake Bay. Va. Inst. Mar. ci. pec. Sci 

Rep. 65, 143 p. 

VAN ENGEL. W. A., W. A. DILLO:--i, D. ZWER"lER, and D. ELDRIDGE

1966. LoxothylacWi panopael (Cirripedia, Sacculinidae) an intro

duced para Ite on a xanthid crab in Chesapeake Bay, U .. A 

Cru taceana 10:110-112. 

,VEl BORD, N. E. 

1975. Cirripedia of Florida and surrounding waters (Acrothoracic 

and Rhizocephala). Bull. Am. Paleont. 68:169-233. 

ZULLO, V. A. 

1963. A preliminary report on systematics and distribution of bar 

nacles (Cirripedia) of the Cape Cod region. Systematics-Ecolo 

Program, Mar. BioI. Lab., Woods Hole, Mass., 33 p. 

1966. Thoracic Cirripedia from the continental shelf off South 

Carolina, U.S.A. Crustaceana 11:229-244. 

ZULLO, V. A., D. B. BEACH, and J. T. CARLTON. 

1972. New barnacle records (Cirripedia, Thoracica). Proc. Cali 

Acad . Sci. 39:65-74. 

ZULLO, V. A., and J. S. BLEAKNEY. 

1966. The cirriped Stomatolepas elegans (Costa) on leatherbad 

turtles from Nova Scotian waters. Can. Field- at. 80:162-165
SYSTEMATIC INDEX 

Acrothoracica . .... ..... . .......... . ... 1, 3, 4, 24 Coronulidae ........................ ... ... 10, 25 

Apoda ...................................... 3 Coronulinae ..... ............................ 25 

Apygophora . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Coronuloidea ........................... ... 5, 25 

Archaeobalanidae ............................ 25 Dosima fascicularis ........................ 22, 24 

Archaeobalaninae ............................ 25 Heteralepas cornuta ........................... 3 

Ascothoracica .......................... .. 2, 3, 4 Kentrogonida .......................... ..... 24 

Balanidae .... . ................ .. ........ 15, 25 

Balanoidea ............................. 5, 6, 25 

Balanomorpha ...... . ....... . .... ....... . 5, 9, 25 

Balanus 

amphitrite .............. ....... 2, 20, 21, 25, 26 

balanoides ... ...... .. ......... see Semibalanus 

balanus ............... ... ............. 17, 25 

calidus ................ ... ............ 2, 8, 25 

crenatus ... . ........................... 19, 26 

eburneus ............................ 2, 18, 26 

hameri .. . . . . . . . . . . . . . . . . . . . . . . . .. see Chirona 

improvisus ............................. 19, 26 

niveus .............. ........... see B. venustus 

subalbidus ............................. 20, 26 

trigonus ............................. 2, 16, 26 

venustus ............................... 20, 26 

Chelonibia ............................ 13, 25, 26 

caretta ................................ 15, 25 

Lepadidae ................................. . 24 

Lepadomorpha ...................... 3, 4, 6, 9, 24 

Lepas .. . . . . .............................. 5, 22 

anatifera ............................ 2, 23, 24 

anserifera ........................ ...... 22, 24 

fascicularis ......................... see Doslma 

hilli . .......... . ...................... 23, 25 

pectinata ....................... ....... 22, 25 

Loxothylacus panopaei ............... ...... ... 24 

niveus, Balanus amphitrite ......... see B. venustus 

Peltogaster 

naushonensis ............................. . 24 

paguri . ................................... 24 

Peltogastridae ............................... 24 

Platylepadinae ................. . .. .......... 25 

Platylepas .................. ... ..... ........ 26 

hexas ty los ............................. 12, 2.') 

patula ..... . .......................... 14, 25 

testudinaria ............................ 15, 25 

Poecilasmatidae ............................. 25 

Proteolepas bivincta ........................... 3 

Chelonibiinae ..................... . ........ 25 Rhizocephala .......................... 1, 3, 4, 24 

Chirona hameri ........... . ............ 15, 16, 25 

Chthamalidae ................ .. ............. 25 

Sacculinidae ................................ 24 

Semibalaninae .............................. 25 

Chthamalinae ............................... 25 Semibalanus balanoides . ................ 11, 25, 26 

Chthamaloidea ............................ 5, 25 

Chthamalus fragilis ....................... 11, 25 

Cirripedia .......................... 1, 2, 3, 9, 24 

Clistosaccidae ............................... 24 

Stomatolepas elegans ...................... 13, 25 

Sylon hyppolytes ............................ 24 

Sylonidae ................................ ... 24 

Thoracica .......................... 1, 3, 4, 6, 24 

Clistosaccus paguri ........................... 24 

Conchoderma ................................ 5 

Trilasmis .................................... 5 

inaequilaterale .......................... 21, 25 

auritum .................... .... ....... 23, 24 Trypetesa lampas .......................... 1. 24 

virgatum ....................... .... . 2, 23, 24 Trypetesidae . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 

Coronula ..... .......................... . 13, 25 Verruca stroemw .......................... ... 3 

diadema ............................... 14, 25 Verrucomorpha ............................. 6, 9 

reginae ................................ 14, 25 Xenobalanus globicipitis .. ..... ......... 13, 21, 25 
ACKNOWLEDGMENTS 

Preparation of the "Marine Flora and Fauna of the Northeastern United States" is being coordinated by the following 

Board: 

Coordinating Editor: Melbourne R. Carriker, College of 

Marine Studies, University of 

Delaware, Lewes, DE 19958. 

Editorial Advisers: Marie B. Abbott, 259 High Street, 

Coventry, Conn. 

Arthur G. Humes, Boston University 

Marine Program, Marine Biological 

Laboratory, Woods Hole, Mass. 

Wesley N. Tiffney, Professor Emeritus, Boston University, 226 Edge 

Hill Road, Sharon, Mass. 

Ruth D. Turner, Museum of Comparative Zoology, Harvard University, Cambridge, Mass. 

28 

Roland L. Wigley, National Marine 

Fisheries Service, Northeast Fisheries Center, NOAA, Woods Hole, 

Mass. 

Robert T. Wilce, Department of 

Botany, University of Massachusetts, Amherst, Mass. 

The Board established the format for the "Marine Flora and 

Fauna of the Northeastern United States," invites systematists 

to collaborate in the preparation of manuals, reviews manuscripts, and advises the Scientific Editor of the National Marine 

Fisheries Service. 

Funds for this study were provided by the SystematicsEcology Program, Marine Biological Laboratory, Woods Hole, 

Mass. , the California Academy of Sciences, and the Program of 

Marine Sciences, University of North Carolina at Wilmington. 

Thanks are expressed to Melbourne R. Carriker whose continued support made the study possible. The illustrations were 

prepared by Susan P. Heller and Ruth L. von Arx. Eugenia L. 

Sick assisted in the final preparation of some of the illustrations. 
PuhllcatlOn of the "~larine Flora and Fauna of thl orlhl'lI, tern \ nlted ::,tllt ~ .. i mo,t lImel~ 10 \ lew 01 th Irro'" 109 

unive~al emphasl. on environmental work and the urg 'nt nel'd 

for 10m' precl~e and complete Idf.'ntillcatllm 01 t'oa lal 

CJrgllni~mb than ha~ been availahlc. It I mandalor', ",here\er 

po~sihle, that organi~m, bt' Identified accurately to peel Ac-

('uratt' bt'ientific namCh unlock the great quantltIe 01 blOlngiCli1 

IOformatlOn stored in lihrarie~, obvlat' duplication 01 rc earch 

IIlready done, and often make po~~ible prediction 01 attribute 01 

organisms that have been inadequlltcly ,tudled 

\lctor Zullo started re~eareh on barnacle- at the OIver~it~ of 

C'altforl1la at Berkeley where he received hi. doctoral degree 

l{esearch on the group wa~ continued in the ,y~tematlc . 

geology Program, VIanne Biological Laboratory, W(K)ds Hole, 

MasR" during the p nod 1 62-67, Emphasib ther wah on the 

taxonomy and dlstnbution of barnacles of the north"'e, tern 

. orth AtlantIc Ocean , He then accepted a pohition at the 

CalifornIa Academy of SCience, an Francisco, 1 hi~ po ition 

wa~ follow d 10 1971 by hiS pre ent one at the Olver, ity of 

North CarolIna at Wilmmg!on , r-." "where he completed the 

manual on barnacles, 

Pr paratlOn 01 this manual was supported in part by a grant 

from the EnVironmental Protection Agency to the Editonal 

Board of the " Manne Flora and Fauna of the :-':ortheastern 

Marine Flora and Fauna of the :-.Iortheastern LOlled tateb: 

port 

\liar 

.\Ian u II. an' not cop)n~ht~d, 

Irom thE' :--OAA I ('hnlcal Heport 

m<hl major IIhranl' 

The manual. 0 far puhh-btd In th 

• ' :\1 F. Cirt ular l'r! are II I d b lov. b\ 

Ir ul r 

• 0 

COOK, DAVID G" and RALPH 0, BRI KHUR 'T Annelida Oligochaela. 

BORROR, ARTHUR ', Protozoa: iliophora, 

MO L, EDWI T, Higher Plants of the Manne Fringe 

Ic LO' KE\, LA WRE CE R. Pycnogolllda , 

MA • I G, RAYMO. D B , Crutacea 'tomatopoda, 

WILLIAMS, AU 'TIN B, Crustacea Decapoda. 

POLLOCK, LELA D W, Tardigrada 

LAR ' 0 ,RONALD J, Cnidana' 'cyphozoa , 

CA VALIERE, A, R. Higher Fungi : As omycete , Deuteromyceotes, and Ha'ldlOm\ 

CO LL, BR CE C, Copepoda' Harpacticoida , 

CLrrLER. Em\ ARD B 'i puncula , 

PA \\,SO:-" , DAVID L, Echin dermata Holothuroldea 

"JU·SH£Y. Copepoda: Lernaeopodldae and 'ph~riidae 

0, ,JU- ' HEY, Copepoda, \'clopold~ Parasitic on Fi, he~ . 

(,RESSE't, ROGER F Crustacea Branchlura 

HO\E£, El GE. E C ,and THO~IA h A\\,YER Protozoa: :arl'odllla: Am b e 

~lLLO, \ICTOR A , Arthropoda Clfrlpedla. 

II