^ L ^ U j U ^ ^ - j , / I . / ? 7 /

(J B i i W w u

Division of Crustade

MATERIALS FOR A REVISION OF THE FAMILY STYLODACTYLIDAE (CRUSTACEA DECAPODA: CARIDEA). JP^fiDHn

I. DESCRIPTION OF A NEW GENUS AND OF A NEW SPECIES

A R M A N D O J. G . F I G U E I R A

Crusin

"tmEBRAT ZOOLOGY

2.a Serie " ^ o ^ Publicagao do Museu e Laboraforio Zoologico e Anfropologico

1971 FACULDADE DE CIENCIAS DE LISBOA

Arq. Mus. Boc. (2.a serie)

vol. Ill n.° 1 pags. 1-8

/ J ( , c: A

A* 7) /L - C c^j,

MATERIALS FOR A REVISION OF THE FAMILY STYLODACTYLIDAE (CRUSTACEA DECAPODA: CARIDEA). I. DESCRIPTION OF A NEW GENUS

AND OF A NEW SPECIES

A B S T R A C T : In the present paper (the first of a small series pro-jected on stylodactylid shrimps) the genus Stylodactylus is redefined, a new genus Parastylodactylus proposed, and a key to the known stylodactylid genera provided; furthermore, it is shown that the Hawai ian stylodactylid referred to Stylodactylus discissipes by M. J. RATHBUN (1906) belongs to an undescribed species.

Described for the first time in 1881, the stylodactylid shrimps have remained until very recently among the least known of the carideans, due to their scarcity in collections and to the inadequacy of the descriptions of most of the recorded species.

A significant contribution to the knowledge of the family under con-sideration was made, however, by K . - I . HAYASHI and S. M I Y A K E with the publication, in 1968, of their partial revision of the Stylodactylidae, in which a new genus, Neostylodactylus, was proposed, and three new species described.

by

A R M A N D O J. G . F I G U E I R A ( I )

(1) Canadian Oceanographic Identification Centre, Nat ional M u s e u m of Natural Sciences, Ottawa, Canada.

2 Armando J. G. Figueira

The genus Neostylodactylus was proposed by HAYASHI and M I Y A K E for those stylodactylids that lack arthrobranchs and a mandibular palp; all the other species of the family were left by them in the old genus Stylodactylus, which they redefined. It must be pointed out, however, that the latter genus, as redefined by HAYASHI and M I Y A K E , contains species both with, and

Text-fig. 1 — Stylodactylus serratus A. MILNE-ED WARDS: Mandible of the holotype.

without a mandibular palp. For this reason, it is evident that it must be split up into two genera, one containing the species with a mandibular palp, and the other, the species without a mandibular palp.

At my request Dr. J. FOREST, of the Museum National d'Histoire Natu-relle, Paris, sent me a camera-lucida drawing of the mandible of the type--specimen of Stylodactylus serratus A. M I L N E - E D W A R D S , 1 8 8 1 (the type-species of the genus Stylodactylus). The drawing (reproduced above as text-figure 1) clearly shows a mandibular palp. For this reason a new genus, Parastylo-dactylus, is here proposed for reception of Stylodactylus bimaxillaris BATE, 1 8 8 8

which, according to HAYASHI and M I Y A K E , has no mandibular palp. A key to the three genera of the Family Stylodactylidae is included below.

A new genus and a new species of stylodactylid shrimps 3

Parastylodactylus gen. no v.

Diagnosis: No mandibular palp; arthrobranchs on pereiopods 1-4; arti-culated spines on both dorsal and ventral margins of rostrum.

Gender: Masculine.

Type-species: Stylodactylus bimaxillaris BATE, 1888.

Key to the known genera of the Family STYLODACTYLIDAE

1) Pereiopods without arthrobranchs; mandibular palp absent Neostylodactylus HAYASHI & M I Y A K E , 1 9 6 8

Pereiopods with arthrobranchs; mandibular palp present or absent 2

2 ) Mandibular palp present Stylodactylus A . M I L N E - E D W A R D S , 1 8 8 1

Mandibular palp absent Parastylodactylus gen. nov.

Several years ago, while attempting to identify a damaged stylodactylid found in a fish stomach at the Funchal fish market, Madeira Island, I asked for and received on loan, from the Smithsonian Institution, Washington, U.S.A., the Hawaiian stylodactylid referred by R A T H B U N ( 1 9 0 6 ) to Stylo-dactylus discissipes BATE, 1 8 8 8 . The Hawaiian specimen proved, however, to belong to a new species, which is described below.

Stylodactylus kauaiensis sp. nov.

Stylodactylus discissipes RATHBUN, 1906, p. 927, fig. 75, pi. 23, fig. 1. [non] Stylodactylus discissipes BATE, 1888, p. 851, pi. 138, fig. 1.

One female, holotype, carapace length (without rostrum) 6.3 mm., Kauai Island, Hawaii, 230-253 fathoms.

Rostrum 1.4 times as long as carapace, armed dorsally with 31 movable spines (of which 7 are on carapace) and ventrally with 9, also movable.

4 Armando J. G. Figueira

Carapace lacking supra-orbital spine and bearing anteriorly antennal and branchiostegal spines (both well developed, antennal being larger of two) and minute pterygostomian spine. Small but distinct orbital furrow and hepatic groove present.

Abdominal somites dorsally rounded, without trace of dorsal carina. Pleura 1-5 broadly rounded and without posterior spine. Fifth abdominal somite (measured dorsally) slightly shorter than sixth; latter bearing pos-terolateral spine at articulation with telson.

Telson (including distal median spine) measuring about 0.6 of length of carapace without rostrum and about 1.5 dorsal length of sixth abdominal somite, ending posteriorly in acute median spine. Three movable spines on each side of median spine, outer one smallest and median one largest. Upper surface of telson broadly grooved from near base to apex. Borders of groove armed with 4 pairs of movable spines. Upper surface of telson, near proximal part, with small hairy protuberance.

Inner uropods attaining apex of telson; outer uropods sub-equal with inner ones and having outer margin distally armed with 2 spines, of which inner one movable and much longer than outer one. Protopodite of uropods armed with acute spine at origin of exterior margin of outer uropod.

Eyes well developed and attaining distal border of first antennular segment. Ocular peduncle narrower than cornea, latter being obliquely set on peduncle.

Antennular peduncle armed with long and acute stylocerite reaching, on left side, about middle of second antennular segment and, on right side, slightly beyond middle of second segment, but not reaching third; third segment shortest, first segment longest. Length of thick (hairy) part of outer antennular flagellum about 0.7 of length of carapace without rostrum.

Second segment of antennal peduncle bearing exteriorly small, very acute spine at base of scaphocerite. Fifth segment of antennal peduncle bearing exteriorly 2 small spinules on distal half; smaller, third spinule above most distal of these 2 spinules, and placed near upper border of segment. Antennal flagella lost. Scaphocerite (including distal spine) 0.5 of length of carapace without rostrum and extending slightly beyond apex of antennular peduncle. Three thin, long, movable spinules on proximal half of outer margin of right scaphocerite; 6 movable spinules (most proximal one smallest) along proximal 2/3 of outer margin of left scaphocerite.

Mandible bearing well developed palp. Maxillula, maxilla, first and second maxillipeds not dissected.

Antepenultimate segment of third maxilliped attaining distal extremity of scaphocerite. Length of distal, penultimate, and antepenultimate segments

A new genus and a new species of stylodactylid shrimps 5

of third maxilliped, sub-equal. Distal segment of left third maxilliped ending in minute spinule (apparently broken on right third maxilliped); distal segment of third maxilliped otherwise unarmed. Upper margin of penultimate segment armed with a series of spinules; additional spinules on outer surface. Distally, on upper and lower margins, penultimate segment bearing stronger spinule. Distal part of antepenultimate segment armed with strong spinules; a number of smaller spinules on outer surface of mentioned segment. Lower margin of distal, penultimate and antepenultimate segments bearing very long setae; numerous spinules among mentioned setae on penultimate and antepenul-timate segments.

Merus of first pereiopod extending slightly beyond apex of scaphocerite. Chela very slightly longer than carapace, about 1.2 times as long as carpus, and sub-equal with merus. Lower margin of fingers, carpus, and merus bearing long setae; lower margin of palm with group of much shorter setae; a few short setae distal part of lower margin of carpus, near articulation with chela. Fixed finger of chela extending very slightly beyond movable finger; both fingers bearing 2-3 extremely small spinules at apex, and armed dorsally with minute spinules, observable under strong magnification. Palm bearing dorsally small, acute spine, another similar spine near base of fixed finger. Upper margin and inner surface of carpus armed with many acute spinules; spinules also on lower margin, near base of setae. Distal border of upper margin, at articulation with chela, armed with quite strong spinule; another similar spinule on distal part of lower margin, very close to articulation with chela. Upper margin of merus unarmed, except for small spinule very close to articulation with carpus. Outer surface of merus densely covered with spinules (increasing in size toward distal part of segment) and also with 2 larger, distal spinules, placed together, and directed distally. Lower margin of merus with minute spinules near base of setae, and with larger distal spinule near articulation with carpus. Inner surface of merus with proximal 1/3 unarmed and distal 2/3 bearing irregular rows of minute spinules; inner surface additionally armed distally with 2 strong spinules near articulation with carpus, one near upper margin of segment, other near lower margin.

Distal extremity of merus of second pereiopod extending very slightly beyond distal extremity of antennular peduncle and attaining apex of blade of scaphocerite. Chela about 1.3 times as long as carpus and about 0.9 length of merus. Apex of fixed finger, unlike first pereiopod, not extending beyond apex of movable finger. Spinulation and pilosity fairly similar to those of first pair.

Carpus of third pereiopod extending nearly to apex of 3rd antennular segment. Propodus very slightly more than 4 times as long as dactylus,

6 Armando J. G. Figueira

1.9 times as long as carpus, and about 0.6 length of merus-ischium. Dactylus armed ventrally with 4 spines increasing gradually in size toward distal part of segment. Small plumose hair dorsally, on proximal third of dactylus; tuft of small setae on the outer-lateral margin, near most proximal ventral spine. Proximal half of upper margin of propodus bearing 4-6 movable spinules; 14 similar spinules along whole length of lower margin. Upper margin of carpus bearing some movable spinules; distal 2/3 of lower margin with 5-6 movable spinules, much larger than those on upper margin, 2 most distal very close to each other. Upper margin of merus bearing about 12-13 movable spinules; stronger spinule on distal border, near carpus. Lower margin of merus armed with 12 spines, increasing in size toward dis-tal part of segment, most distal one pointing quite distally, not obliquely as the others. Inner side of lower margin of merus, at articulation with carpus, with movable spinule. Both propodus and carpus densely covered with long setae; setae also present on merus.

Merus of fourth pereiopod reaching about middle of scaphocerite. Pro-podus almost 5 times as long as dactylus, about 2.3 times as long as carpus, about 0.75 length of merus, and very slightly more than 4 times as long as ischium; latter fused with merus, but suture clearly visible. Armature and pilo-sity of dactylus similar to those of 3rd pereiopods. Propodus bearing 8 movable spinules on proximal 2/3 of upper margin and 13-14 ones along whole length of lower margin. Carpus bearing several movable spinules on upper margin; 5 movable spinules on lower margin (larger than those on upper margin), 2 most distal very close to each other. Upper margin of merus armed with about 9-10 movable spinules; much stronger one near carpus. Lower margin of merus armed with 12-13 spines, increasing gradually in size toward distal part of segment, most distal one pointing quite distally; a movable spine on inner side of lower margin near articulation with carpus.

Merus of fifth pereiopod reaching about to base of stylocerite. Propo-dus about 5 times as long as dactylus, slightly more than twice length of carpus, about 0.9 of length of merus, and about 4 times as long as ischium. Dactylus armed ventrally with 6 spines, increasing gradually in size toward distal part of segment. As in 3rd and 4th pereiopods, dactylus of 5th pereiopod bearing small plumose seta dorsally on proximal third, as well as tuft of small setae on outer-lateral margin, near most proximal of ventral spines. Proximal 2/3 of upper margin of propodus bearing 10-12 movable spinules; 16 movable spinules along whole length of lower margin of propodus, penul-timate much larger than others, and distal one placed close to dactylus. Upper margin of carpus bearing several movable spinules; five movable spinules (larger than those on upper margin) on distal half of lower margin, 2 most

A new genus and a new species of stylodactylid shrimps 7

distal ones placed close to each other and larger than remaining 3, most pro-ximal one of latter smallest. Merus bearing dorsally on distal third 2-5 minute, movable spinules, as well as much stronger one at articulation with carpus; lower margin bearing 10 strong spines, increasing gradually in size toward distal part of segment and placed obliquely, except most distal one pointing distally (although not as much as counterparts on 3rd and 4th pereiopods). Movable spinule on inner side of lower margin of merus, near articulation with carpus.

DISCUSSION

Stylodactylus kauaiensis, by possessing a series of spinules on the outer margin of the scaphocerite, differs from all known species of the genus, except S. rectirostris A . M I L N E - E D W A R D S , 1 8 8 3 and S. multidentatus K U B O , 1 9 4 2 .

It can, however, be distinguished at once from those two species by the absence of a supra-orbital spine.

The holotype of the present species is deposited in the National Museum of Natural History, Smithsonian Institution, Washington, D.C., U.S.A., and bears the U.S.N.M. Catalogue No. 31009.

I wish to thank Dr. FENNER A. CHACE, JR., National Museum of Natural History, Smithsonian Institution, Washington, D . C . , U . S . A . , not only for being instrumental in arranging the loan of the specimen on which the description of Stylodactylus kauaiensis is based, but also for reviewing the present translation of my original Portuguese manus-cript. I a m also indebted to Dr. JACQUES FOREST, Laboratoire de Zoologie (Arthropodes), Museum National d'Histoire Naturelle, Paris, France, fo i dissecting and drawing, at my request, the mandibles of the holotype of Stylodactylus serratus A. MILNE-EDWARDS, and to Dr. KEN-ICHI HAYASHI, Zoological Laboratory, Faculty of Agriculture, Kyushu Univer-sity, Fukuoka, Japan, for the loan of a specimen of Stylodactylus major HAYASHI & MIYAKE.

8 Armando J. G. Figueira

REFERENCES

BATE, C. S. (1888) — Report on the Crustacea Macrura collected by H .M.S . Challenger during the years 1873-76. Rept. Voy. Challenger, Zool., 24, I-CX, 1-942, t e x t - f i g s . 1 - 7 6 , p i s . 1 - 1 5 0 .

HAYASHI, K.-I. & MIYAKE, S. (1968) — Notes on the Family Stylodactylidae with description of a new genus Neostylodactylus. J. Fac. Agric., Kyushu Univ., 14 (4), 583-611, text-figs. 1-7.

KEMP, S. (1925) — Notes on Crustacea Decapoda in the Indian Museum. XVII. On various Caridea. Rec. Indian Mus., 27 (4), 249-343, text-figs. 1-24.

KUBO, I. (1942) — On two new species of Decapoda Macrura. Annot. Zool. Jap., 21 (1), 30-38, text-figs. 1-5.

MAN, J. G. DE ( 1 9 2 0 ) — T h e Decapoda of the Siboga Expedition. Part IV. Families Pasiphaeidae, Stylodactylidae, Hoplophoridae, Nematocarcinidae, Thalassocari-dae, Pandalidae, Psalidopodidae, Gnathophyllidae, Processidae, Glyphocrango-nidae and Crangonidae. Siboga Exped., Monogr. 39a3, 1-318, pis. 1-25.

MILNE-EDWARDS, A. (1881) — Description de quelques Crustaces Macroures provenant des grandes profondeurs de la Mer des Antilles. Ann. Sci. Nat., ser. 6 , 1 1 (4), 1-16.

(1883) — Recueil de Figures de Crustaces Nouveaux ou Peu Connus. Pis. 1-44. Paris.

RATHBUN, M. J. (1906) — T h e Brachyura and Macrura of the Hawaiian Islands. Bull. U.S. Comm. Fish and Fisheries for 1903, pt. 3, 1906, 827-930, text-figs. 1-79, pis. 1 - 2 4 .

Os A R Q U I V O S D O M U S E U B O C A G E pub l i cam t r a b a l h o s or ig inais de Z o o l o g i a , A n t r o p o l o g i a e Biologia G e r a l , rea l izados ou n a o n o M u s e u e L a b o r a t o r i o Z o o l o g i c o e A n t r o p o l o g i c o da F a c u l d a d e de Ciencias da U n i v e r s i d a d e de L i s b o a . Os or ig inais devem ser env iados a o Ed i t o r e c a d a t r a b a l h o cons t i t u i r a u m fasc icu lo , q u e sera d i s t r i bu ido sepa-r a d a m e n t e . C a d a v o l u m e sera cons t i t u ido , e m pr inc ip io , p o r q u a t r o c e n t a s a q u i n h e n t a s paginas , inc lu indo as « N o t a s e S u p l e m e n t o s » e p o d e r a c o r r e s p o n d e r a u m ou ma i s a n o s civis.

O titulo dos or ig inais , d a c t i l o g r a f a d o s a dois espa<;os, deve ra ser conc i so e bem defi-n i d o e o(s) nome(s ) do(s) au to r ( e s ) v i rao seguidos pelo da Ins t i tu igao o n d e t r a b a l h a ( m ) .

R e c o m e n d a - s e q u e a o t i tu lo se siga u m «abstract» q u e n a o excedera as 50 pa lavras . O tex to d o a r t igo devera ser c o m p l e t a d o p o r u m resumo em F r a n c e s , Ingles o u A l e m a o . R e c o m e n d a - s e q u e a bibliografiu seja a p r e s e n t a d a c o m o a b a i x o se indica . A o s a u t o r e s se rao conced idas 100 s e p a r a t a s gra t is . P o d e r a o ser e n c o m e n d a d a s cop ias

ex t ra . O c o n t e x t o dos a r t igos e da intei ra r e sponsab i l i dade d o s respect ivos au to re s .

Les A R Q U I V O S D O M U S E U B O C A G E publ ien t des t r a v a u x su r Zoo log ie , A n t h r o p o l o g i c et Biologie Gene ra t e , realises soit p a r des a u t e u r s po r tuga i s , soit pa r des a u t e u r s e t r anger s . Les t r a v a u x do ivent e t re envoyes a l ' E d i t e u r et c h a c u n d ' eux c o m p o -sera un fascicule qui sera d i s t r ibue tou t de suite. Les vo lumes se ron t cons t i tues p a r un n o m b r e var iable de fascicules , y c o m p r i s « N o t a s e Sup len ien tos» , qui a u r o n t q u a t r e cents a cinc cents pages sans per iodic i te annuel le .

Le titre des t r a v a u x devra e t re concis et bien defini . Le n o m de l ' a u t e u r sera suivi pa r celui de I ' Ins t i tu t ion ou il t ravail le . Les ar t icles dev ron t e t re dac ty log raph i e s a d o u b l e interl igne. 11 est souha i t ab l e q u ' e n tete de Particle l ' a u t e u r fasse f igurer un «abstract» qui ne devra pas exceder 50 m o t s .

Le texte de Part icle devra e t re suivi d ' u n resume en f ranga is , angla is o u a l l e m a n d . La b ib l iographie devra e t re presentee selon l ' exemple d o n n e plus bas . L ' a u t e u r a u r a dro i t a 100 tires a par t g ra tu i t s . Des copies s u p p l e m e n t a i r e s peuven t e t re

c o m m a n d e e s . Le texte des ar t icles sera de la responsab i l i t e exclusive des a u t e u r s respectifs .

T h e A R Q U I V O S D O M U S E U B O C A G E c o n t a i n s or iginal pape r s , m a d e by Por tuguese o r fore ign a u t h o r s , within the genera l field of Z o o l o g y , A n t h r o p o l o g y a n d G e n e r a l Biology. M a n u s c r i p t s shou ld be sent to the Ed i to r . Each p a p e r will f o r m a sepa ra t e n u m b e r wich a p p e a r s , at i r regu la r in tervals , as it b e c o m e ready . Vo lumes will have a b o u t f o u r o r five h u n d r e d pages , i nc lud ing « N o t a s e S u p l e m e n t o s » , a n d will not necessarily be comple t ed within the c a l e n d a r year .

T h e title of the pape r s shou ld be concise a n d specific a n d the name(s ) of the au tho r ( s ) shou ld be a c c o m p a i n e d by that of the ins t i tu t ion to wich he be longs .

An abstract will be pr in ted at the head of all pape r s , tha t shou ld general ly no t exceed 50 words . A summary, in English, F rench or G e r m a n , shou ld give a succint a ccoun t of the subjec t , results a n d conc lus ions .

A u t h o r s a re reques ted to present the literature a r r a n g e d a lphabe t ica l ly a c c o r d i n g the s u r n a m e s of the a u t h o r s . Refe rences will be indicated as bel low.

O n e h u n d r e d repr in ts of each paper will be suppl ied f ree , add i t i ona l copies m ay be pu rchased . T h e text is of A u t h o r ' s exclusive responsabi l i ty .

COBOS, A. ( 1 9 6 8 ) — S e g u n d a especie n u e v a de Xenorhipis p a r a S u d a m e r i c a Arq. Mus. Bar. (2." ser.) , 2, n. s. 16: X X V I I - X X X I .

E d i t o r : P r o f . D r . G . F . SACARRAO

Direc to r , M u s e u Bocage

F a c u l d a d e de Ciencias R. Escola Pol i tecnica , 58 L I S B O A ( 2 ) PORTUGAL

I M 1> R F N S A

I)!•" C'OIMBRA,

I.IMI 1 ADA