CRUSTACEAN RESEARCH. NO. 34: 4n--52. 2005 Description of Coutieralpheus setirostris, new genus, new species, an infaunal alpheid shrimp (Crustacea: 1 Decapoda) from Florida, U.S.A. -I .I ~ Arthur Anker* and Darryl L. Felder* * Abstract.- Coutieralpheus, new objects of num erous taxonomic and ecolog i­ genus, is established for C. setirostris, cal studies that reveal their surprisingly high new species, on the basis of two speci­ morphological and phylogen etic diversity. mens, a complete male and an incom­ Twelve alpheid genera tLeptalbh eus plete female, collected from burrows Williams, 1965 (s. I.), Fenneralph eus Feld er on the tidal flats bordering Fort Pierce & Manning , 1986, Amphibetaeus Coutiere, Inlet on the Atlantic coast of Florida, 1896, Salmon eus Holthuis, 1955, Deioneus U.S.A. The new genus belongs to a large Dworschak, Ank er & Abed-Navandi, 2000, group of alpheid genera characterized Orygmalpheus De Grave & Anker, 2000, I by the presence of a posteroventral Betaeus Dan a, 1852, Athanas Leach, 1814, articulated plate on the sixth abdomi­ Athanopsis Coutiere , 1897 . Stenalpheops I nal pleuron. The holotype male bears Miy a, 1997 (= Chelomalpheus Kim, 1998, = i J robust, subsymmetrical and equal-sized Ca uipelta Hayashi, 1998), Automate de Man , I cheIipeds. The mesial side of the che­ 1888 and Alpheus Fabricius, 1798) include ~ I liped carpus bears several rows of about 20 species reported as obligate or fac­ short setae, which are present in only ultative assoc iates of burrowing animal s three other, non-related alpheid gen­ suc h as th alassinidean mudshrimps, larger era. The two thickened terminal setae burrowing alpheids, crabs. sto matopo ds, on the rostrum are also diagnostic. echiura ns, acorn worms, mud gobles and Coutieralpheus appears to combine mudskippers (e.g., Couti ere, 1899: Schmitt, 1 primitive and highly evolved features 1926; Hart, 1964; 'Williams, 1965; Dawson , and is presumably related to the mono­ 1967; Salornan, 1971: Chace & Abbott, 1980; typic genus Deioneu s Dworschak, Miya, 1980, 1984; Felder & Manning, 1986; 1 Anker & Abed-Navandi from the Berggren , 1991: Branch et al., 1994; Feld er Eastern Atlantic. However, in some et al., 1995, 20m; De Grave & Wilkin s, 1997; characters the new genus also resem­ Felder & Manning, 1997; F roglia & bles the genera Sod.mone u.s Holthuis, Atkin s on , 1998; Hayashi, 1998, 2002 ; Atpheopeis Coutfere and Parabetaeu... Dworschak & Coelho, 1999; Dworsch ak et Gou t.Ier e. The host of C. setirostris al., 2000;De Grave & Anker, 2000; Nomura, r emains unknown, although both the 2000: Anker et al., 2001 ; Anker, 2003a; holotype and paratype w ere collected Sillima n et al. , 2003; Itani, pers. corn m.: from substrates richly burrowed by tha­ Anker, pers, obs.). lassinidean shrimp, stomatopods, and S ha llo w marine waters of sou thern large polychaetes. Florida harbor a rich assemblage of infaunal alpheids . w ith three d escrib ed s pe cies, Leptalph eus forceps William s , 196 5, Introduction Feiineralpheus chacei Feld er & Manning, Infaunal alpheid s h r im ps h ave be en 1986 and Salmo ne us cauicolu s Felder & 1• NEW ALPHEID GENUS FROi\·1FLORIDA 4 1 Manning , 1986 (Salom an , 1971, Fe lde r & Museum of Natural History, Sm ithsonian Manning , 1986; Feld er et al., 2003) and at In stitution , Wash ington D.C ., U.S .A. least five more kn own but as ye t unde­ (USNM). scribe d species, three putatively assignable or very closely relat ed to Lepialpheus and two assignable to Salmoneus aft cauicolus Taxonomy (Felder & Manning, 1997; Felder et al., 2003; Alphe idae Rafinesque, 1815 Felder, pers. obs.; Anke r, pers. obs.) . In Co u riera lp h.eue, new genus addition to the aforementi oned undescrib ed Diagnosis.-Carapace glabrous, with forms is also a very peculiar undescrib ed very fine ly mar ked anterolateral suture; alpheid collecte d fro m burrows of an branchiostegial margin of carapace without unknown host on intertidal sand flats bor­ pro nounced ventra l lip; frontal region with dering Fort Pierce Inlet on the Atlanti c coast rostrum bearing 2 th ickened setae, orbital of Florid a. Because of the unique combina­ teeth absent; pterygostomial angle produced tion of morphologi cal feature s th is new ante riorly, rounded ; eyes co mp lete ly co n­ s pecies could not be a s si gned to any cea led in dorsal view, partly visible in lateral pre sentl y kn own genus of th e fa m ily and frontal view, eyestalk without anterome­ Alp heida e . T h is s pecies is herewith sial process or tubercle; antennular pedun­ describ ed and placed in a new ge nus. cle robust, first segment with ventromesial tooth; s ty locerite short, robust, not appressed; second segment not elongated; Mate rials and Me thods o ut er a n tennular flagellum biramous; Specimens were collected by sieving sed­ ma nd ible typical fo r family, with incisor iments ex tracted with a bait suct ion pump, process be aring tria ngular di stal tee th , also termed a "yabby pump" (see Manning, molar proc ess bearin g a row of lamellae and 1975), that was applied to burrow openings setae, and with short 2-seg mented palp; first o n an tida l mudflat of th e Indian River max illiped with caridean lobe expanded; sec­ Lagoon near the Fort Pierce Inlet, St. Lucie ond maxillip ed with epipod elongate; third Cou nty, Florida. Specimens we re initially max illiped pediform, lateral plate con spicu­ fixed in 10% buffered formali n solution and ously elongate, subacute, terminal segment subseq uent ly pre served in 70% e thanol. with rows of long, distally thickened setae, Drawings were made with the aid of a cam­ tip armed with 1 small su bdistal spine; first era lucida, and most were based on moulted pe re iopods (chelipeds) enlarg ed , equal in exuvia of the holotype specime n (thus avoid­ size and sha pe, ro bust, carried extended; ing the dissection of the appe ndages and the major che liped with ischium bearing 1 spine resulting unavoidable damage of th e unique on ventrolater al margin; merus robu st, ven­ complete spe cime n). An alcohol based solu­ trally not depressed or excavated; carpus tion of Chlorazole Black E s ta in (Sig ma s hort, robust , cup -s haped, mesially with Chemical Company®was used to enhance rows of setae; chela subcylindrical; palm visibility of fine sutures and artic ulations in smooth, lin e a impressa ab sent; cutting the integumen t pr io r to ill us trat io n. edges of fingers armed with irregular teeth, Carapace le ngth (Cl.) an d the total len gth snapping mechanism abs ent; adhesive discs (TL) were measured in ± O. l mm with a cali­ absent; second pereiopod with 5-segmented brated oc ular microm et er. Measure me nts carpus; third pereiopod ischi um and merus were made along the dorsomedial line from armed with spines on ventral margin, carpus the rostral tip to the posterior margin of the unarm ed; propodu s armed with small spines carapace (CL), or to the posterior margin of on ventral margin. dactylus s imp le; fifth the telso n (TL). The type specimens were pereiopod with ischiu m and meru s deposited in the collections of the National u narmed, propodus with well developed 42 A. ANKER & D. L. FELDER brush of setae; sixth abdominal segment Description.-Body relatively stout, slight­ with articulated plate at posterolateral angle; ly elongated (Fig. 1), not particularly com­ second male pleopod with appendix interna pressed laterally, carapace and abdomen and appendix masculina; uropod with exo­ glabrous. Carapace with distinct suture prox­ pod bearing lateral spine and diaeresis, lat­ imal to base of antenna (Figs. 1, 2a). ter without particular modifications; telson Rostrum triangular, broad at base, longer with 2 pairs of dorsal spines and 2 pairs of than wide, rostral carina very slight, termi­ posterolateral spines, posterior margin nus bearing 2 thick anteriorly directed setae rounded, anal tubercles absent; gill formula (Fig. 2a). Orbital teeth absent (Fig. 2a, b) . typical for family: 5 pleurobranchs (Pl-5), 1 Pterygostomial angle protruding anteriorly, arthrobranch (Mxp3), 0 podobranch, 2 rounded (Fig. 2b). Branchiostegial margin lobed epipods (Mxpl-2), 5 strap-like epipods with scant setae (Fig. 2g). Cardiac notch = mastigobranchs (Mxp3, Pl-4), 5 sets of well developed (Fig. 2g). Eyes completely setobranchs (Pl-5), 3 exopods (Mxpl-3). covered by carapace, not visible in dorsal view, exposed in lateral and anterior view, without anteromesial process or tubercle, Type species.-·Coutieralpheus setirostris, cornea well developed (Fig. 2a, b). Ocellar new species. beak not conspicuous. Epistornial sclerite with low, subacute process, without pro­ Gender.-Masculine. nounced acute tooth. Etymology.-This new genus is dedicated to Antennular peduncle stout (Fig. 2a, d), Professor Henri Coutiere (1869-1952), an second article not much longer than first or eminent French carcinologist, for numerous third; stylocerite almost reaching distal mar­ contributions to the knowledge of alpheid gin of first article, distally acute or subacute shrimps that included a major monograph of (Fig. 2a); ventromesial carina with blade-like the family Alpheidae (Coutiere, 1899). tooth as illustrated (Fig. 2d); lateral flagel­ Coutiere was the first author to report the lum biramous, with shorter ramus well association of an alpheid shrimp with cal­ developed, situated at 4th segment (Fig. 2d). lianassid ghost shrimp and other burrowing Antenna with basicerite bearing strong ven­ animals in Djibouti. trolateral tooth (Fig. 2b); scaphocerite broadly oval, anterior margin of blade con­ Relationships.-See remarks under vex, slightly protruding beyond distolateral Coutieralpheus setirostris, new species.