15 October 1992 PROC. BIOL. SOC. WASH. 105(3), 1992, pp. 562-570 REDESCRIPTION OF THE HIPPOLYTID SHRIMP TRACHYCARIS R UGOSA (BATE) (CRUSTACEA: : ) FROM THE WESTERN ATLANTIC, WITH NOTES ON SEXUAL DIMORPHISM

Maria M. Criales

Abstract. - Trachycaris rugosa (Bate, 1888) is redescribed and figured based on specimens from the western Atlantic. This species shows a remarkable sexual dimorphism in size, shape and length of the rostrum, abdominal pleura, ven- tromedian abdominal spines, and antennular peduncle. Trachycaris rugosa differs from the eastern Atlantic Trachycaris restricta (A. Milne Edwards, 1878) in the absence of a palp on the mandible, the presence of two spines on the basal antennal peduncle, and a two-segmented palp on the first maxilliped.

While examining material of Trachycaris tus," "rugosa" and "restricta" will be used rugosa (Bate, 1888) from the National Mu- in this paper to agree with the feminine Tra- seum of Natural History, Smithsonian In- chycaris. stitution, Washington, D.C. (USNM), to de- termine the identity of some specimens of Trachycaris collected in Santa Marta, Co- Trachycaris rugosa (Bate, 1888) lombia, it was found that, with the excep- Figs. 1-5 tion of one specimen from Bermuda (USNM Platybema rugosus Bate, 1888:579, pl. 104, 35 963)' the IJSNM and Santa Marta spec- fig. 2. [type locality: off Culebra Island, imens represent the same species. The spec- Puerto Rico, depth 390 fm (7 13.3 m)]. imens agree with the original description of Trachycaris rugosus: Calman, 1906:33. Trachycaris rugosa (Bate, 1888), and differ Trachycaris restrictus: Holthuis, 1949:233, from the eastern Atlantic T. restricta Hol- figs. 2-3 (in part, see remarks). thuis (1949) in that in the former a palp is absent on the mandible, there are two spines Material examined. -Colombia: 2 6, Isla on the antennal peduncle, and the palp of de la Aguja ca. 1 1°18'N, 74"101W,25 m, 8 the first maxilliped is two-segmented. Also, Aug 1987, on calcareous algae, coll.: B. considerable sexual dimorphism was found Werding, USNM 252485; 1 P ovig., Santa in the specimens of T. rugosa, especially Marta, ca. 11°13'N, 74"9'W, 8 m, Feb 1980, reflected in size, shape of the rostrum, ab- sand, coll.: B. Werding, USNM 252485. domen and antennular peduncles. Barbados: 1 P ovig. Barbados-Antigua Exp., Total length (TL) of the specimens was English Harbor 8, USNM 125 144. measured from the anterior tip of the ros- Virgin Islands: 1 P juv. off St. Thomas, trum to the posterior median margin of the 20 ft (36.6 m), coral, Feb 1899, USNM telson, and carapace length (CL) was mea- 2469 1. sured from the tip of the rostrum to the Puerto Rico: 2 P ovig., off Culebra, R/V posterior median margin of the carapace. Fish Hawk 15 fm (27.4 m), coral sand, Feb Although the Trachycaris species are typ- 1899, USNM 24692, 24964; 2 P ovig., off ically designated as "rugosus" and "restric- Jallabor Bay, July 19 15, USNM 1135, 1179; VOLUME 105, NUMBER 3

2 P, Mayaguez, on coral reef, 20 Jan 1899, apace similar, different from adults (Figs. USNM 24690. la, 2a); dorsal ridge rising behind eye and Mexico: 1 P ovig., Yucatan, off Cape Ca- sloping down to rostrum, more pronounced toche, 22'18'N, 87"04'W, R/V Albatross, 24 with size in females, tending to be flat in fm (43.9 m), USNM 23308. males (Figs. Ib, 2b). Carapace with several Cuba: 1 9, S. of Hicacos, Varadero, 2 Jan tubercles ending in anteriorly directed spines 1957, dredge haul, coll W. Schmitt, USNM variable in size and location but with fol- 213537. lowing general pattern: behind cervical Belize: 1 P ovig., Stann Creek District, groove a row of 3-4 spinules, and another Carrie Bow Cay, May 198 1, on the alga Rhi- 3 or 4 forward (absent in juveniles); row of pocephalus sp., USNM 1845 10. 4-5 tubercles beginning behind antennal Gulf of Mexico: 1 P ovig., off Charlotte spine and running along lateral surface; un- Harbor 26'33'N, 83'10fW, 28 fm (51.2 m), der this row another 3-6 tubercles near lat- 2 Apr 1901, sand, R/V Fish Hawk, USNM eral margin of carapace; near highest point 24693; 2 P ovig. 1 P juv., between of dorsal ridge there is another group of tu- 29'14'30"N, 85'32'W and 29'1 6'N, bercles variable in number. Adult females 85'32'W, R/V Albatross, 24-27 fm (43.9- with additional group of tubercles near pos- 49.4 m), 30 Jan 1885, USNM 23770,23771, terolateral margin of carapace. Juveniles 9599. with fewer and smaller tubercles. Upper Florida Keys: 3 P ovig., 1 P juv., Dry Tor- margin of orbit with distinct supraorbital tugas, 27 fm (49.4 m), Jan 1925, coll. W. L. spine, lower angle ending in sharp ptery- Longley, USNM 144662, 127956, 127957, gostomial spine; anterior margin with a 127958, 2 P, S. of Cape San Blas, strong antennal spine, below which are 3 29'1 1' 18"N, 85'29'32"W, R/V Albatross, other small spines on anterolateral angle of 25-27 fm (45.749.4 m), 7 Feb 1885, USNM carapace (Figs. la, b; 2a, b). 23769, 2374. Antennular peduncle with basal segment South Carolina: 7 8, off S. Carolina, between with distinct, large stylocerite, ending in 2 3 1'3 lf54"N, 78'39'42"W, and 32'49' 18"N, processes. Proximal process tapering into 78'49'18"W, between 33-68 m, Aug 198 1, sharp anteriorly directed tip, the other suction sampler, USNM 224965, 224966, rounded but with distinct spine at the top. 224967, 22070, 2207 1, 224989. Between 2 processes a deep, rounded notch. Redescription.-Carapace varying con- Ventral surface with strong curved spine di- siderably with size and sex (Figs. la, b; 2a, rected to outside of peduncle. In males, sec- b). Rostrum of adult females strongly com- ond segment robust and short about l/3 length pressed laterally, approximately as long as of third. Flagella short, consisting of about high, tip truncated with 5-6 small teeth; 6 articles (Fig. 2d). In females, second seg- lower margin with 3 large teeth, upper mar- ment slightly longer than third, flagella con- gin with 6 or 7 teeth (Fig. l b). Dorsomedian sisting of approximately 8 articles (Fig. Id). ridge of carapace sloping sharply down to Antennal scale overreaching antennular rostrum, with several teeth distinctly larger peduncle by about '/3 of its length, about than those of rostrum, unequal in size. Adult twice as long as broad; outer margin ending males with elongate rostrum, approximate- in distinct terminal tooth overreaching the ly twice as long as high, ending in 2 apical lamella. Antennal peduncle bearing 1 small teeth, tip truncated with 34small teeth; dorsal spine and 2 large ventral spines, larg- lower margin with 3 rather large teeth; up- est located near base of scaphocerite, small- per margin with 6 teeth, continuing in rel- est near distal border. Antennal flagellum atively straight line to dorsomedian ridge consisting of 15 or 16 articles (Fig. 3g). (Fig. 2b). Juveniles of both sexes with car- Mandible lacking palp. Molar process with PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON

Fig. 1. Trachycaris rugosa Bate, females from Puerto Rico (USNM 2469 1, 1135). a, carapace of juvenile female; b, carapace of adult female; c, abdomen of juvenile female, ventrolateral view; d, antennular peduncle of female, ventral view. strong conical tooth medially, and series of veloped exopod. First maxilliped with 2 en- small serrate teeth (Fig. 3a). dites separated by distinct notch. Palp dis- Maxillule with slender bilobed endopo- tinctly segmented, provided near the base dite; upper lacinia broad, distal margin with with accessory lobe. Epipod slender, dis- about 25 ,ines; lower lacinia with tinctly bilobed (Fig. 3d). few long distal setae (Fig. 3b). Second maxilliped with 5-segmented en- Maxilla with setose distal endite distinct- dopodite. Dactylus short, as long as broad, ly cleft, proximal endite setose with single with dense fringe of setae along dorsodistal lobe; palp short, thumblike, scaphognathite margin. Propodus slightly shorter than car- well developed (Fig. 3c). pus, also bearing numerous long simple se- Maxillipeds each provided with well de- tae (Fig. 3e). VOLUME 105, NUMBER 3

Fig. 2. Trachycaris rugosa Bate, males from South Carolina (USNM 224966) and Colombia (USNM 252485). a, carapace ofjuvenile; b, carapace of adult; c, abdomen of adult, ventrolateral view; d, antennular peduncle of adult, ventral view.

Third maxilliped robust, exceeding an- peds. Finger acute, about 3/, as long as palm, tennular peduncle by tip of ultimate seg- fixed finger ending in 2 black claws. Palm ment, endopodite well developed, 4-seg- somewhat swollen, produced posterior to mented. Ultimate segment about twice as articulation with carpus. Carpus short, long as penultimate segment, bearing 7 slightly longer than broad, about 2/3 the length strong dark spines. Penultimate segment ofthe chela. Merus and ischium slightly lon- slightly shorter than antepenultimate; on ger than carpus (Fig. 4a). dorsal surface bearing 3 rows of terminal Second pereiopods equal and slender. spines variable in number (first row 6-8, Finger nearly '/3 as long as palm. Carpus second 8-1 0, third 10-1 8). Antepenulti- about 1.5 times as long as chela, consisting mate segment bearing large spine on outer of 2 joints of equal length. Merus slightly anterolateral angle and 2 rows of setae on longer than chela (Fig. 4b). dorsal surface (first row 2-10, second 6-8). Last 3 legs robust, short. Third pereiopod Exopod long, slender, reaching anterolateral exceeding antenna1peduncle by entire length spine of antepenultimate segment (Fig. 30. of carpus. Posterior margin of dactylus with First pereiopods small, rather heavy, 3-5 teeth, distal one largest; propodus near- reaching middle of merus of third maxilli- ly twice as long as dactylus, posterior margin PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON

0.5 mm a-f - 0.5 mm g-h 7 Fig. 3. Trachycaris rugosa Bate, male from Colombia (USNM 252485). a-f, mouth parts, right external view: a, mandible; b, maxillula; c, maxilla; d, first maxilliped; e, second maxilliped; f, third maxilliped, dorsal view; g, antenna, ventral view; h, telson and sixth abdominal somite. bearing 4 spinules; carpus about half length fifth somites bearing only 1 ventromedian of merus, bearing 4 or 5 strong spines on spine. Females with pleura broadly round- dorsal surface, ventral margin with strong ed, also with minute denticles (generally 3 spine at anterior point (Fig. 4c, d); dorsal or 4). Juvenile females armed on first to surface of merus with 2 spines on inner mar- third somite with 2 small ventromedian ab- gin, and 2 spines near middle. Fourth and dominal spines, fourth and fifth with a sin- fifth pereiopods similar to third (Fig. 4e, f). gle spine. Immature females (LT 5 1 1.5 mm) Abdomen having anterior 2 somites with still having 1 ventromedian spine on both lateral, short grooves, third to sixth somites fourth and fifth somite (Fig. lc). Ovigerous smooth. Males with abdominal pleura large, females lacking all ventromedian abdomi- narrow (Fig. 2c). Apexes of first to fifth pleu- nal spines. Fifth abdominal somite in fe- ra ending in marginal teeth with minute males and males with large spine on lateral denticles (generally 2 or 3). First to third surface of pleura. Sixth somite with very abdominal somites armed with 2 strong narrow pleura ending in strong posterior ventromedian abdominal spines, fourth and spine without minute denticles and bearing VOLUME 105, NUMBER 3

Fig. 4. Trachycaris rugosa Bate, male from Colombia (USNM 252485) and female from Puerto Rico (USNM 1135). a, first pereiopod of male; b, second pereiopod of male; c, third pereiopod of male, dorsal view; d, third pereiopod of male, ventral view; e, fourth pereiopod of female, dorsal view; f, fourth pereiopod of female, ventral view. -- a-h - Fig. 5. Trachycaris rugosa Bate, female from Puerto Rico (USNM 1 135) and male from Colombia (USNM 252485). a, first pleopod of female; b, second pleopod of female; c, third pleopod of female; d, fourth pleopod of female; e, fifth pleopod of female; f, first pleopod of male; g, second pleopod of male; h, third pleopod of male.

4 large, strong terminal spines similar in est in females, with narrow endopodite twice size; another 3 large spines are on dorsal as long as basipodite and longer than en- surface alternately placed between 4 ter- dopodite. First pleopods lacking appendix minal spines (Fig. 3h). interna (Fig. 5a). Second to fifth pleopods Telson broadly oval, with blunt apex. bearing a very small rounded appendix in- Lateral margin each bearing 4 movable terne ending in tiny curved hairs. Second spines. Anterior pair of spines located an- pleopods with broad discoidal endopod terior to middle of telson, second pair placed about 1.3 times longer than wide, exopodite midway between first spine and posterior narrow (Fig. 5b). Second to fifth pleopods end of telson (Fig. 3h). Two posterior pairs generally similar, third pleopod largest, de- smaller, similar in size near the apex. creasing in size posteriorly (Fig. 5b-e). In Uropods well developed. Exopodite dis- males, first to fifth pleopods biramous, all tinctly broad with outer margin slightly lacking appendices. First pleopods with very rounded and ending in tooth; inner side small and rounded endopodite and large and bearing movable spine often difficult to ob- narrow exopodite. Second to fifth pleopods serve in juveniles. Endopodite narrowly similar in shape and size (Fig. 5f-g). ovate, fringed with plumose setae (Fig. 3h). Measurements. -9 ovig. TL = 11.12-29.3 Pleopods biramous, first pleopods small- mm, CL = 5.7-12.5 mm; P non-breeding VOLUME 105, NUMBER 3 569

LT = 5.4-1 1.12 mm, LC = 2.57-5.70 mm. erous female of T. restricta. The main dif- 8 LT = 6.96-1 1.32 mm, LC = 3.03-5.65 ferences are: lack of a palp on the mandible; mm. two spines on the basal antennal peduncle Color. -In life, abdomen and carapace instead of three; two-segmented palp of the bright red with some white spots in distal first maxilliped; lower endite of the maxilla part of rostrum, orbit of eye, telson and out- present; ventral surface of the antennular er edge of pleura. Pereiopods with trans- peduncle with a large curved spine; and sev- verse irregular white and red bands, except eral rows of spines on the third maxilliped. on the second pair. This color pattern ap- These characteristics were shared by all pears to be mimicry, as the specimens were but one of the 19 females in the USNM found living on calcareous algae of a similar collection. The sole exception, a female from red-pinkish color. Color of preserved ma- Bermuda, showed the mandible, the anten- terial is variable, some specimens keeping nal peduncle, and the first maxilliped as in a dark brown color, while in others the color Holthuis's (1 949) description of T. restricta. disappears entirely. The other differences between Holthuis's Distribution. -Western Atlantic from description and the characteristics observed South Carolina through Gulf of Mexico and in the USNM material may be due to in- Caribbean Sea to Santa Marta, Colombia. accuracies in the description, because these Remarks. -The genus Trachycaris Cal- structures appear different when viewed man (1906) was founded to receive Platy- from ventral and dorsal perspectives. Until bema rugosus Bate, 1888, a species that un- it is possible to compare greater number of til 1940 was known only from the western specimens from the eastern and western At- Atlantic (Gurney 1940). Holthuis (1 949) lantic to determine the extent of variation compared material of T. rugosa from the of this species, it is best to separate the east Canary Islands and a single T. rugosa spec- Atlantic species, T. restricta, from the west imen from Curaqao with material of T. re- Atlantic species, T. rugosa. strict~A. Milne Edwards from the Cape Kemp (1 9 14) described variation in the Verde Islands, and concluded that the east- proportional lengths of the third maxilli- ern and western Atlantic forms should be peds and first pereiopods of males of the one species, T. restricta. The Cura~aoand hippolytids Saron marmoratus and Canary Island specimens differed in several australis from young adulthood to senility. significant details from Bate's figures, lead- In addition, females and males of Latreutes ing Holthuis to conclude that Bate's draw- mucronatus exhibited a remarkable diver- ings of the western Atlantic specimen were sity in the form of the rostrum as well as inaccurate, and that both forms should be the proportions of the antennal scale and considered as one species. Although Hol- the spinulation of the anterolateral margin thuis accurately described and compared the of the carapace. Sexual dimorphism in other specimens he observed, he may have hippolytids has been reported in Lebbeus wrongly assumed that Bate's descriptions of polaris, Spirontocaris liljeborgii and S. the mandible were inaccurate. phippsii, with differences found mainly in Noteworthy variations in morphology the shape and length of the rostrum, which were found among the specimens of T. re- become more pronounced with increasing strict~in the USNM collection, due in part age (Greve 1963, Squires 1965). Chace to sexual dimorphism and age. In addition, (1 972) reported a large difference in size be- significant differences were found between tween males and females of Thor dobkini. the ovigerous females in the USNM collec- Although some hippolytids, like Spironto- tion and Holthuis's description of an ovig- caris spp., possess ventral abdominal spines 570 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON

(Greve 1963), they are not considered to be support (NOAA #NA90RAH00075). This an indication of sexual dimorphism. Sexual research was supported by a short-term vis- dimorphism in the hippolytid Trachycaris itor grant from the Office of Fellowships and rugosa is based mainly on the presence of Grants, Smithsonian Institution. ventromedian abdominal spines in the males, lack of appendices in all the pleopods Literature Cited in the males, more rounded abdominal Bate, C. S. 1888. Report on the Crustacea Macrura pleura in females, different proportion of collected by H. M. S. Challenger during the years segments in the antennular peduncle, and 1873-76. Report on the scientific results of the different spination and shape of the cara- voyage of H.M.S. Challenger, Zoology, 24, xc pace. Similar features were reported by Goy + 942 pp., pls. 1-150. & Felder (1988) in the stenopodid Micro- Calman, W. T. 1906. Notes on some genera of the family Hippo1ytidae.-Annals and prosthema manningi. Magazine of Natural History, Series 7(17):29- Males of T. rugosa of the USNM collec- 34. tion, which are smaller and less abundant, Chace, F. A., Jr. 1972. The shrimps of the Smith- come from only two different localities: sonian-Bredin Caribbean Expeditions with a South Carolina (U.S.A.) and Isla de Aguja summary of the West Indian shallow-water spe- cies (Crustacea: Decapoda: Natantia). - Smith- (Colombia). The South Carolina specimens sonian Contributions to Zoology 98:i-x, 1-1 79. were collected by suction sampler between Goy, J. W., & D. L. Felder. 1988. Two new species 33-68 m in depth, and the Colombian spec- of Microprosthema from the western Atlantic imens were collected by hand in 25 m among (Crustacea: Decapoda: Stenopodidea). -Jour- calcareous algae. Females examined were nal of Natural History 22(5): 1277-1292. Greve, L. 1963. The genera Spirontocaris, Lebbeus, collected in different parts ofthe Caribbean, Eualus and Thoralus in Norwegian waters (Crust. Gulf of Mexico and Bermuda, in depths be- Dee.).-Sarsia 11:29-42. tween 8-20 m, on sand or coral. Based on Gurney, R. 1940. The larvae of the decapod genus this information, it is reasonable to con- Trachycaris Calman.-Proceedings of the Zoo- clude that males are more cryptic and live logical Society of London, Series B (1 10):121- 125, pls. 1-3. in deeper water than females, and that these Holthuis, L. B. 1949. The caridean Crustacea of the differences in habitats could possibly ac- Canary Islands.-Zoologe Mededelingen Uit- count for morphological differentiation. gegeven door het Rijksmuseum van Natuurlijke Historie te Leiden 30(15):227-325, 8 figs. Acknowledgments Kemp, S. 1914. IV. Notes on Crustacea Decapoda in the Indian Museum. V. . -Rec- I express my gratitude to Dr. F. A. Chace, ords of the Indian Museum 10 11, (4):81-128, Jr., USNM, for his kind advice, suggestions, pls. 1-6. Milne Edwards, A. 1878. Description de quelques and curatorial assistance; Dr. R. Lemaitre, esptces nouvelles de CrustacCs provenant du USNM, for providing the opportunity to voyage aux iles du Cap-Vert de MM. Bouvier visit the USNM; to Ms. K. Ryan, USNM, et de Cissac.-Bulletin de la SociCtC Philo- for assistance in the drawings; Dr. B. Werd- mathique de Paris, Series 7, 2:225-232. ing, Institute of General and Special Zool- Squires, H. J. 1965. Decapod of New- foundland, Labrador and the Canadian eastern ogy, University of Giessen, Germany, for Arctic.-Fisheries Research of Canada, Manu- providing the Santa Marta specimens. Also script Report Series (Biological) 8 10:1-2 12. thanks go to the staff of the Instituto de Investigaciones Marinas de Punta de Betin Rosenstiel School of Marine and Atmo- (INVEMAR), Santa Marta, Colombia, and spheric Science, Division of Marine Biology Dr. M. McGowan of the Southeast Florida and Fisheries, 4600 Rickenbacker Cause- and Caribbean Recruitment Project (SEF- way, Miami, Florida 33149-1098, U.S.A. CAR), University of Miami, for logistical