Echinopericlimenes dentidactylus ( Bruce, 1984 ) Bruce, 1984

Marin, Ivan & Chan, Tin-Yam, 2014, Deep water echinoid-associated pontoniine shrimp “ Periclimenes hertwigi Balss, 1913 ” species group (Crustacea: Decapoda: Caridea: Palaemonidae): species review, description of a new genus and species from Philippines, Zootaxa 3835 (3), pp. 301-324 : 318-322

Echinopericlimenes dentidactylus ( Bruce, 1984) comb. nov.

( Figs. 7 )

Periclimenes dentidactylus Bruce, 1984: 7 , figs. 1–6 [type locality—Borneo, Indonesia, 592-595 meters]. — Chace & Bruce, 1993: 108, fig. 22.

Material examined. Philippines: 1 male (pcl 6.5 mm) ( NTOU M01749 ), PANGLAO 2005, stn. CP 2362, 8854.69N, 123833.79E, off Cebu Island, depth 679–740 meters, sandy bottom, 26 May 2005.

Diagnosis. Large-sized species with subcylindrical body ( Fig. 12 ). Carapace smooth, non pitted, swollen, with antennal and hepatic teeth; hepatic tooth larger than antennal, situated close to pterygostomial margin of carapace with the tip overreaching it ( Fig. 13 b). Rostrum long, slender, compressed, turned forward, overreaching antennular peduncle; dorsal carina with 6–7 large dorsal teeth, 2 proximal teeth situated posterior to the level of orbit; ventral margin feebly developed, with 2 large teeth situated at the distal third of the length of rostrum; distal ventral tooth situated slightly anterior the level of the most distal dorsal tooth, the second ventral tooth situated slightly anterior to the level of the second dorsal tooth; proximal lateral rostral lamina feebly developed ( Fig. 13 a); pterygostomial angle rounded. Abdominal somites smooth; pleurae of abdominal somites I–V rounded ( Fig. 12 ). Telson ( Fig. 13 c) stout, about 3 times longer than proximal width, narrowing distally, with 2 pairs of small dorsal marginal spines situated at 0.45 and 0.75 of telson length; distal margin of telson armed with 3 pairs of spines. Eyes ( Fig. 13 a, b) large, with large oval cornea and relatively stout conical eyestalk. Antennula well developed, compressed; basal segment with distolateral angle armed with large tooth and medial rounded projection, with small ventromesial tooth. Antenna normal, basicerite armed with large lateral tooth, overreaching the segment, with long slender carpocerite and well developed wide scaphocerite bearing sharp distolateral tooth slightly overreaching the blade. Mouthparts characteristic for the genus, without specific features. Pereiopod I with slender segments; palm ( Fig. 13 e) about twice longer than wide, equal to fingers; dactylus and fixed finger simple, with entire cutting margins and simple tips; polex furnished with several tufts of simple setae along ventral margin. Pereiopods II (chelipeds) similar in shape and slightly unequal in size ( Fig.13 f–i); major pereiopod II ( Fig. 13 f, d) with slender merus and ischium bearing small teeth along ventral margin, smooth dorsally; carpus small, triangular in shape, slightly overlapping carpo-propodal articulation, with straight margins; propodus cylindrical, covered with small blunt tubercles, about 3 times as long as wide; fixed finger (polex) about 2.5 times as long as wide, about 2.5 times shorter than palm, covered with blunt tubercles along ventral margin, with large triangular tooth proximally and well developed slightly convex cutting edge distally, with curved and simple tip; movable finger (dactylus) relatively stout, equal to polex, with large triangular tooth proximally and well developed slightly concave cutting edge distally, tip curved, simple; minor pereiopod II ( Fig. 13 h, i) generally similar to major one but smaller. Pereiopod III relatively slender, with unarmed proximal segments; carpus slender, unarmed, with produced distodorsal margin overlapping carpo-propodal articulation; propodus slender, about 7 times as long as wide, with straight lateral margins, with 5 single slender spines situated along ventral margin and several slender spines, which about half of the length of the dactylus, situated at distoventral angle ( Fig. 13 j), with tuft of stout flattened setae at dactylo-propodal articulation; dactylus ( Fig. 13 j) relatively slender, about 3.5 times as long as wide, with straight ventral margin, with several strong teeth at distoventrally ( Fig. 13 k); unguis small and curved, proxy-ventrally serrated, with distal part smooth, unarmed. Uropods normal, well developed; distolateral angle of exopod sharply produced, with single movable spine.

Remarks. The examined male specimen is identical to holotype male from Indonesia described by Bruce (1984) and female specimen from Philippines described by Chace & Bruce (1993). The species clearly separates from the congeners by having long rostrum armed with well developed dorsal and ventral teeth, which are stronger than in any other species within the genus. For other morphological differences see the key presented above.

Coloration. The only known color photo of this species is presented in this paper ( Fig. 14 a), but the already dead shrimp specimen was photographed and the coloration mainly disappeared. General coloration of body and appendages is probably uniformly deeply red without any white pigmentation.

Host. Unknown. Possibly, similarly to other representatives of the genus the species is associated with deepwater venomous sea urchins (Echinodermata: Echinoidea).

Distribution. The species is presently known from Indonesia, 592–595 meters (the type locality; Bruce, 1984) and Philippines, 679–1280 meters ( Chace & Bruce, 1993; the present study).

Figures

FIGURE 7. Echinopericlimenes calcaratus (Chace & Bruce, 1993) comb. nov., male from Philippines, 100 – 140 m (NTOU M 01743) (a, d, e), ovigerous female from Philippines, 80 – 90 m (NTOU M 01745) (b), ovigerous female from Philippines, 194 m (NTOU M 01746) (c, g – l): a – c — rostrum and front of carapace, lateral view; d – g — pereiopods II, distal segments; h – i — pereiopods II; j, k — distal propodus and dactylus of pereiopod III; l — same, distal part of dactylus (without scale).

FIGURE 12. Echinopericlimenes dentidactylus (Bruce, 1984) comb. nov., male from Philippines, 679 – 740 m (NTOU M 01749), general lateral view.

FIGURE 13. Echinopericlimenes dentidactylus (Bruce, 1984) comb. nov., male from Philippines, 679 – 740 m (NTOU M 01749): a, b — rostrum and front of carapace; c — telson; d — distolateral angel of uropodal exopod; e — distal segments of pereiopod I; f, g — major pereiopod II; h, i — minor pereiopod II; j — distal propodus and dactylus of pereiopod III; k — same, distal part of dactylus.

FIGURE 14. Echinopericlimenes dentidactylus (Bruce, 1984) comb. nov., male from Philippines, 679 – 740 m (NTOU M 01749) (a); Echinopericlimenes calcaratus (Chace & Bruce, 1993) comb. nov., non-ovigerous female from Philippines, 80 – 90 m (NTOU M 01745) (b), non-ovigerous female from Philippines, 194 m (NTOU M 01746) (c); Ecinopericlimenes aurorae sp. nov., holotype male from Philippines, 336 m (NMCR) (d, e), male from Philippines, 273 – 302 m (NTOU M 01742) (f), non-ovigerous female from Philippines, 357 – 367 m (NTOU M 01748) (g, h).