The sponge-dwelling snapping shrimps (Crustacea, Decapoda, Alpheidae, Synalpheus) of Discovery Bay, Jamaica, with descriptions of four new species Author Iii, Kenneth S Macdonald Author Hultgren, Kristin Author Duffy, Emmett text Zootaxa 2009 2199 1 57 journal article 10.5281/zenodo.189568 c668ee01-6eff-451a-9b96-be6f14b35edc 1175-5326 189568 Synalpheus plumosetosus , n. sp. Figures 17–21 Material examined. Jamaica : Holotype : non-ovigerous individual, CL: 2.55 mm , ( USNM 1126369, original VIMS 08JAM2706), Dairy Bull Reef, (18° 28.083΄ N, 77° 23.289΄ W), from canals of Auletta cf. sycinularia . Allotype: ovigerous female, CL: 2.62 mm , ( USNM 1126370, original VIMS 08JAM2704), Dairy Bull Reef, from canals same of same individual Auletta cf. sycinularia as holotype . Paratypes : non-ovigerous individual, CL: 2.59 mm , ovigerous female, CL: 2.47 mm , ( USNM 1126371,1126372, original VIMS 08JAM2705,07), Dairy Bull Reef, from canals same of same individual Auletta cf. sycinularia as holotype . MaxCL ovigerous female: 2.62 mm . MaxCL non-ovigerous individual: 2.55 mm . Description. Body form subcylindrical; carapace smooth, sparsely setose, posterior margin with cardiac notch distinct. Rostrum longer than ocular hood ( Fig. 17 , 18 ), distinctly narrower, distally upturned; margins in dorsal view, slightly concave. Ocular hoods dorsally convex; in dorsal view, blunt, separated from rostrum by deep adrostral sinus. Stylocerite acute, with blunt tip; mesial margin concave; reaching beyond midpoint of first segment of antennular peduncle. First antennular segment without ventromesial tooth, and with two basal ventral processes. Basicerite without tooth on dorsomesial corner, with longer ventrolateral spine, reaching distal end of third segment of antennular peduncle. Scaphocerite without blade, acute lateral spine robust, with lateral margin slightly concave, slightly shorter than basicerite spine, reaching almost to distal end of third segment of antennular peduncle. Third maxilliped with distal circlet of approximately six spines on distal segment, without ventrodistal spine on antepenultimate segment. Major first pereopod ( Fig. 17 , 18 ) massive, fingers clearly shorter than half length of palm; fixed finger slightly shorter than dactyl. Palm of chela with tapering acute distal protuberance on superior margin, directed slightly downward, towards dactyl. Minor first pereopod ( Fig. 19 ) with palm clearly less than two times longer than high; fingers clearly shorter than palm; dactyl with flexor margin concave, blade-like, with small but distinct second tooth basal to strongly curved tip; extensor surface of dactyl with thick brush of curved, plumose setae; fixed finger with flexor margin straight, blade-like, and small but distinct second tooth basal to strongly curved tip. Second pereopod ( Fig. 20 ) with carpus 5-segmented, subequal in length to merus. Both fingers terminating in a narrow, curved tooth. Third pereopod ( Fig. 20 ) slender; dactyl biunguiculate, with flexor unguis subequal in thickness to extensor, mesial margin of flexor unguis strongly convex; propodus with row of six movable spines on flexor margin and one pair of distal movable spines flanking base of dactyl; carpus with distal movable spine on flexor margin; merus 3 ½ times longer than wide, without movable spines on flexor margin. Fourth pereopod ( Fig. 20 ) similar to third, weaker, propodus with five spines on flexor margin. Fifth pereopod ( Fig. 20 ) weaker than fourth; propodus with only four spines on flexor margin, and four transverse combs of stout setae on ventral face; carpus without distal spine. First pleura ( Fig. 17 ) of male with posterior corner distinctly produced ventrally into short, blunt, downward directed point; second pleura of male broadly rounded. Third to fifth pleura of male with straight ventral margin, rounded anterior corner and subacute posterior corner. First pleopod ( Fig. 21 ) of male with 2 terminal setae on endopod; second pleopod of male with marginal setae on exopod originating in distal one-half; appendix interna present on second to fifth male pleopods. Second pleopod ( Fig. 21 ) of female with marginal setae on exopod originating in distal one-half; appendix interna present on second to fifth female pleopods. Telson ( Fig. 17 , 18 ) with convex lobe on distal margin; posterior corners adjacent to spines obtuse. Space between distal spines 25% of distal margin, lateral spines ~70% length of mesial. Distal margin ~30% width of proximal margin. Uropods ( Fig. 17 ) with a single fixed tooth on lateral margin of exopod distinctly removed anteriorly from the movable spine, the latter longer and thicker than adjacent posterior fixed tooth. Colot in life. Nondescript, translucent with dull gold tinge to thickened parts of cuticle; distal palm and fingers of major chela orange; ovaries and embryos drab green. FIGURE 17. Synalpheus plumosetosus n. sp. Holotype non-ovigerous individual CL: 2.55 mm (USNM 1126369, original VIMS 08JAM2706), from Auletta cf. sycinularia , Dairy Bull Reef , Jamaica: A, carapace, anterior region, and cephalic appendages, dorsal view; B, chela of major first pereopod, ventral view; C, telson and left uropods, dorso-lateral view. Allotype ovigerous female CL: 2.62 mm (USNM 1126370, original VIMS 08JAM2704) from Auletta cf. sycinularia , Dairy Bull Reef , Jamaica: D, carapace, anterior region, and cephalic appendages, dorsal view; E, chela of major first pereopod, anterior region, ventral view; F, telson, dorsal view. Scale bar = 0.4 mm for A, C, D, E, F; 0.75 for B. FIGURE 18. Synalpheus plumosetosus n. sp. Paratype ovigerous female CL: 2.59 mm (USNM 1126371, original VIMS 08JAM2705), from Auletta cf. sycinularia , Dairy Bull Reef , Jamaica: A, carapace, anterior region, and cephalic appendages, dorsal view; B, chela of major first pereopod, anterior region, ventral view; C, telson, dorsal view. Paratype non-ovigerous individual CL: 2.47 mm (USNM 1126372, original VIMS 08JAM2707), from Auletta cf. sycinularia , Dairy Bull Reef , Jamaica: D, carapace, anterior region, and cephalic appendages, dorsal view; E, chela of major first pereopod, anterior region, ventral view; F, telson, dorsal view; G, abdomen, lateral view. Scale bar = 0.4 mm for A, B, C, D, E, F; 0.5 for G. FIGURE 19. Synalpheus plumosetosus n. sp. Holotype non-ovigerous individual 2.55 mm (USNM 1126369, original VIMS 08JAM2706), from Auletta cf. sycinularia , Dairy Bull Reef , Jamaica: A, minor first pereopod, setae removed, mesial view; B, same, distal region. Allotype ovigerous female CL: 2.62 mm (USNM 1126370, original VIMS 08JAM2704) from Auletta cf. sycinularia , Dairy Bull Reef , Jamaica: C, chela of minor first pereopod, distal region, setae removed, lateral view. Paratype non-ovigerous individual CL: 2.47 mm (USNM 1126372, original VIMS 08JAM2707), from Auletta cf. sycinularia , Dairy Bull Reef , Jamaica: D, chela of minor first pereopod, distal region, lateral view. Scale bar = 0.33 mm for A; 0.2 mm for B, C, D. FIGURE 20. Synalpheus plumosetosus n. sp. Holotype non-ovigerous individual CL: 2.55 mm (USNM 1126369, original VIMS 08JAM2706), from Auletta cf. sycinularia , Dairy Bull Reef , Jamaica: A, second pereopod; B, same, detail of distal region; C, third pereopod; D, same, detail of distal region; E, fourth pereopod; F, same, detail of distal region; G, fifth pereopod; H, same, detail of distal region. Scale bar = 0.33 mm for A, C, E, G; 0.15 for B, D, F, H. Etymology. We have named this species for its distinguishing characteristic: the plumose setae making up the setal brush on the minor chela. Variation. There is variation in the relative lengths of the scaphocerite and basicerite among the four specimens examined. In the holotype and allotype (USNM 1126369,70), the scaphocerite is longer than the basicerite, while in the two paratypes (USNM 1126371,72), the scaphocerite is shorter. Hosts and ecology. All four individuals were collected from the canals of Auletta cf. sycinularia (Plate 7B). This sponge appears to be the same species from which all samples of Synalpheus irie , n. sp. were also collected. Distribution. Jamaica (this study). FIGURE 21. Synalpheus plumosetosus n. sp. Holotype non-ovigerous individual CL: 2.55 mm (USNM 1126369, original VIMS 08JAM2706), from Auletta cf. sycinularia , Dairy Bull Reef , Jamaica: A, first pleopod; B, second pleopod. Allotype ovigerous female CL: 2.62 mm (USNM 1126370, original VIMS 08JAM2704) from Auletta cf. sycinularia , Dairy Bull Reef , Jamaica: C, first pleopod; D, second pleopod. Scale bar = 0.2 mm. Remarks. Synalpheus plumosetosus n. sp. appears to be another member of the complex of morphologically similar species that includes S. brooksi , S. bousfieldi , S. chacei , S. corallinus n. sp. and S. thele n. sp. (see Table 3 ). Synalpheus plumosetosus can be easily distinguished from all of these by the setal brush on the dactyl of its minor chela, which consists of plumose setae rather than the simple setae found in all other examined Synalpheus species. In most other characters, S. plumosetosus resembles S. bousfieldi .