Salmoneus poupini Anker, 2011, n. sp.
Creators: name: Anker, Arthur
Publisher: name: Zenodo
Year: 2011
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Decapoda
Alpheidae
Salmoneus
Salmoneus poupini

description: Salmoneus poupini n. sp.
(Figs. 8–11)
Type material. French Polynesia, Society Islands, Moorea. Holotype: ovigerous specimen (CL 5.0 mm), FLMNH UF Arthropoda 28070, Moorea lagoon, public beach between Temae point and Sofitel, sand flat with coral “bommies”, depth 0.5–2 m, snorkeling, coll. A. Anker, 30 November 2010 [fcn BMOO-15433]. Paratypes: 1 ovigerous specimen (CL 3.7 mm), FLMNH UF Arthropoda 23307, Moorea lagoon at Pihaena, near broken stone jetty, sand and mud bottom with large coral “bommies” and coral rubble, adjacent to deep channel with fine sand bottom, deep under large pieces of rubble and corals, depth 0.5–1.5 m, snorkeling, coll. A. Anker, 23 October 2009 [fcn BMOO-06752]; 1 ovigerous specimen (CL 4.1 mm), FLMNH UF Arthropoda 23311, Moorea lagoon at Papetoai, shallow sand flat with abundant coral rubble and coral “bommies”, deep under rubble and massive corals, depth 0.5–1 m, snorkeling, coll. A. Anker, 3 November 2009 [fcn BMOO-08209]; 1 non-ovigerous specimen (CL 2.7 mm), FLMNH UF Arthropoda 23314, Moorea lagoon at Pihaena, near broken stone jetty, sand and mud bottom with large coral “bommies” and coral rubble, adjacent to deep channel with fine sand bottom, deep under large pieces of rubble and corals, depth 0.5–1 m, snorkeling, coll. A. Anker, 21 October 2009 [fcn BMOO-06473]; 1 ovigerous specimen (CL 4.9 mm), OUMNH.ZC 2011-03-171, Moorea lagoon, between Cook’s Bay and Hilton, off Pihaena, sand flat with corals and rubble, under large coral “bommies” on sand and loose rubble, depth 3–4 m, scuba diving, coll. A. Anker, 23 November 2010 [fcn BMOO-15434]; 1 non-ovigerous specimen (CL 2.6 mm), RMNH D 53396, Moorea lagoon, same collection data as previous specimen [fcn BMOO-15820]; 1 non-ovigerous specimen (CL 2.5 mm), FLMNH UF Arthropoda 28068, Moorea lagoon, Pihaena near broken pier, mud-silt flat with coral “bommies” and rubble, deep under large pieces of rubble or corals, depth less than 1 m, snorkeling, coll. A. Anker, 26 October 2010 [fcn BMOO-13077]; 1 non-ovigerous specimen (CL 3.6 mm), FLMNH UF Arthropoda 28069, Moorea lagoon, public beach between Temae point and Sofitel, sand flat with coral “bommies”, depth 0.5– 2 m, snorkeling, coll. A. Anker, 30 November 2010 [fcn BMOO-15432].
Additional material. 1 non-ovigerous specimen (CL 6.1 mm), ZRC 2011.0034, The Philippines, Bohol, Panglao Island, Panglao Marine Biodiversity Project Sta M7, Momo Beach, reef platform with sea grass depth 0–3 m, suction (yabby) pump, from Glypturus mound, coll. P.C. Dworschak, 1 June 2004 [fcn PD3].
Description. Medium to relatively large-sized species of Salmoneus (CL of adults CL 4.1–6.1 mm). Carapace more or less domed (more in larger individuals), sparsely covered with minute shallow pits and stubby setae; anterolateral region with faint suture (Fig. 8 A, B); cardiac notch deep. Rostrum moderately long, distinctly over-reaching distal margin of first article of antennular peduncle, subtriangular, longer than wide at base, horizontal to slightly descendant in lateral view, without distinct medio-dorsal carina; lateral margins faintly concave; tip acute, straight, not curved upwards; ventral margin unarmed (Fig. 8 A, B). Orbital teeth small compared to rostrum, subtriangular, acute distally, directed slightly anteromesially (Fig. 8 A, B). Pterygostomial angle broadly rounded (Fig. 8 B).
Pleura of first four abdominal somites rounded posteroventrally; fifth pleuron with posteroventral angle sharply projecting posteriorly (visible in Fig. 10 B); sixth somite without distinct articulated plate, with faint suture only; preanal plate rounded. Telson slender, widest at base, distally tapering; dorsal surface with two pairs of spiniform setae inserted at some distance from lateral margin, at about 0.5 and 0.75 telson length, respectively; posterior margin about half as long as anterior margin, truncate, with broad median emargination and two pairs of long spiniform setae, mesial being distinctly longer than lateral; margin between mesial spiniform setae furnished with one pair of plumose setae (Fig. 8 D).
Eyes partly concealed in dorsal view, anterior-most portion visible in both dorsal and lateral view; cornea slightly reduced; anterolateral margin not protruding anteriorly (Fig. 8 A, B). Epistomial sclerites with strong subacute processes.
Antennular peduncles stout, with second article about as long as wide; stylocerite with acute to subacute tip almost reaching distal margin of second article; ventromesial carina with small, anteriorly directed tooth; lateral flagellum biramous, fused portion very short; accessory ramus with three to five groups of aesthetascs (Fig. 5 A, B). Antenna with basicerite ending in stout tooth distoventrally; scaphocerite ovate, with broad, anteriorly rounded blade reaching well-beyond acute distolateral tooth, latter not reaching beyond end of antennular peduncle; carpocerite very short, stout, reaching half-length of scaphocerite (Fig. 1 A, B, D).
Mouthparts typical for genus. Third maxilliped slender; coxa with lateral plate above mastigobranch somewhat produced dorsally, subquadrate; penultimate article about three times as long as wide, widening distally, with one distinct transverse rows of dense serrulate setae on mesial side; ultimate article furnished with transverse rows of thick serrulate setae mesially, tapering distally, apical region with corneous tip and at least one stout subapical spiniform seta; arthrobranch well developed (Fig. 8 E–H).
Chelipeds unequal in size, asymmetrical in shape, minor cheliped ranging from 0.5 to 0.8 length of major cheliped, slightly more slender, with chela slightly smaller and with shorter fingers (Figs. 9 A, E, 10, 11); both chelipeds folded under cephalothorax when not in use. Major cheliped elongate, slender; ischium distally widening, with one small spiniform seta on ventrolateral surface; merus about four times as long as wide, smooth, depressed distoventrally, ventral margin somewhat convex; carpus elongate, more or less 0.7 length of merus, ventrally depressed, distally widening (Fig. 9 A, B); chela somewhat compressed, smooth, ventral margin strongly concave at pollex base; fingers distinctly longer than palm, with tips strongly curved and crossing; cutting edge of dactylus with three to five (usually four) widely spaced, small, subacute teeth; space between large teeth slightly convex, finely striated; cutting edge of pollex with three or four teeth similar to those of dactylus (Figs. 9 C, D). Minor cheliped slightly less robust than major cheliped, with palm more or less inflated (in some specimens palm about the same size as palm of major chela), however, fingers distinctly shorter and less slender than those of major cheliped; ischium with stout spiniform seta on ventrolateral surface; merus about four to five times as long as wide, smooth, depressed ventrally; carpus vase-shaped, somewhat elongate, distally widening (Fig. 9 E, F); chela smooth, simple, with fingers stout, about 0.6 length of palm; cutting edges serrated with at least three broadly rounded interdigitating teeth; tips moderately curved, not strongly crossing (Fig. 9 G).
Second pereiopod slender; ischium with two spiniform setae on ventrolateral surface; merus about the same length as ischium; carpus five-articulated, ratio of carpal articles (from proximal to distal) subequal to: 5: 1: 1: 1.3: 1.7; chela simple, slightly longer than most-distal carpal article (Fig. 8 I). Third pereiopod slender, compressed; ischium with two to three spiniform setae on ventrolateral surface; merus about seven times as long as wide, unarmed; carpus much more slender than merus, about 0.7–0.8 merus length, with small spiniform seta distoventrally; propodus with usually three spiniform setae along ventral margin and one pair of stouter and longer distal spiniform setae adjacent to dactylus; dactylus almost 0.5 propodus length, simple, moderately slender, gradually curving distally, with setae at about 0.7 dactylar length (Fig. 8 J, K). Fourth pereiopod similar to third pereiopod. Fifth pereiopod slender, slightly longer than third pereiopod; ischium unarmed; propodus with well-developed setal brush distolaterally (Fig. 8 L).
Male second pleopod with appendix masculina shorter than appendix interna, apex and distomesial margin furnished with stiff setae (Fig. 8 M). Uropod with lateral lobe of protopod bearing subacute tooth; endopod and exopod narrowly ovoid; diaeresis sinuous, with small distolateral tooth adjacent to slender spiniform seta (Fig. 5 O). Gillexopod formula typical for genus.
Colour in life: semitransparent, hyaline-whitish, with bright yolk-yellow gonads or freshly-laid eggs (Figs. 10, 11).
Variation. The eight type specimens from Moorea differ considerably in age and size, the smallest paratype (CL 2.5 mm) being half the size of the holotype, the largest specimen in the type series (CL 5.0 mm). Accordingly, they differ allometrically in the proportions of the carapace, the length of the rostrum, the relative eye size, the ratio of cheliped articles, and most conspicuously, in the size of the minor cheliped relative to the major cheliped (cf. Figs. 10 A, B, 11). There is also some variation in the number of teeth on the finger cutting edges of the major chela: most specimens have four teeth on the dactylus, the holotype has five teeth (Fig. 10 C), and one of the smallest specimens has only three teeth. The Panglao specimen (CL 6.1 mm) is larger than the holotype from Moorea, but otherwise quite similar (Fig. 11 C, D); like in most Moorea specimens, the cutting edges of the major chela fingers bear four teeth.
Etymology. Named after Dr. Joseph Poupin (Ecole Navale, Brest, France) for his significant contributions to the taxonomy of Decapoda, especially in French Polynesia.
Ecology. Moorea: lagoon and lagoon fringing reefs, sand and loose rubble with large coral “bommies”, depth range 0.5–4 m (most specimens in less than 1 m); deep in sand and loose rubble, under large pieces of coral rubble and coral “bommies”. Panglao: reef platform with sand and sea grass; possibly associated with a burrow of Glypturus sp. (Callianassidae).
Type locality. Moorea, Society Islands of French Polynesia, southwestern Pacific Ocean.
Distribution. Presently known only from Moorea lagoon (Papetoai, Pihaena, Temae) and Panglao, off Bohol, the Philippines.
Remarks. Salmoneus poupini n. sp. is undoubtedly closely related to both S. paulayi n. sp. and S. komaii n. sp., both assigned to the S. jarli species group (see above). The new species from Moorea differs from S. paulayi n. sp. by the longer rostrum; the dorsally partly exposed eyestalks; the presence of spiniform setae on the ischium of the second and third pereiopods; the narrower scaphocerite; the presence of less dense setal rows on the mesial face of the penultimate article of the third maxilliped; and the much less conspicuous lamellar convexities on the finger cutting edges of the major chela (cf. Figs. 1–3, 8, 9). Salmoneus poupini n. sp. appears to be more closely related to S. komaii n. sp., from which it can be separated by the much smaller teeth on the finger cutting edges of the major chela; the anterolaterally non-angular eyestalks; the absence of a minute ventral subapical tooth on the rostrum; the relatively longer carpus of the major cheliped; the narrower telson; and the mesial spiniform setae on the posterior margin of the telson being longer than the lateral ones vs. the opposite in S. komaii n. sp. (cf. Figs. 5, 6, 8, 9). Salmoneus poupini n. sp. can also be distinguished from S. sketi by a very differently shaped frontal margin of the carapace; the broader, distally more tapering telson; the shorter stylocerite; and several other features (cf. Fransen 1991).
description: Published as part of Anker, Arthur, 2011, Three new species of the alpheid shrimp genus Salmoneus Holthuis, 1955 (Crustacea, Decapoda) from the tropical western Pacific, pp. 67-84 in Zootaxa 2839 on pages 78-83, DOI: 10.5281/zenodo.208086