Triodonthea setosa, Macpherson, Enrique & Robainas-Barcia, Aymee, 2013

Macpherson, Enrique & Robainas-Barcia, Aymee, 2013, A new genus and some new species of the genus Lauriea Baba, 1971 (Crustacea, Decapoda, Galatheidae) from the Pacific and Indian Oceans, using molecular and morphological characters, Zootaxa 3599 (2), pp. 136-160 : 155-159

Triodonthea setosa n. sp.

(Figs 7, 8F)

Material examined. Holotype: Solomon Islands. SALOMON 1. Stn DW1840, 10°17.0'S, 161°43.0'E, 97–223 m, 6 October 2001: 1 M 3.2 mm (MNHN-IU-2010-5262).

Paratypes: New Caledonia. SMIB 5. Stn DW100, 23°22.90'S, 168°05.20'E, 80–120 m, 14 September 1989: 1 ov. F 4.8 mm (MNHN-IU-2010-5263). NORFOLK 2, Stn CP2141, 23°00.52'S, 168°19.80'E, 92–100 m, 3 November 2003: 1 M 3.5 mm, 1 ov. F 4.0 mm (MNHN-IU-2010-5264).

Etymology. From the Latin, setosus, bristly, in reference to the numerous long setae on the body.

Description. Carapace: as long as wide, dorsal surface covered with long and short fine setae, some of them plumose, arising from numerous short transverse ridges; 2 spines on epigastric region, (paratype with additional pair of epigastric spines and 1 postcervical spine on each side). Cervical groove indistinct. Lateral margins convex, with 6 or 7 small but distinct spines on each side, last spine sometimes absent or located mesial to lateral margin; first (anterolateral) small, remainder more or less distantly separated from one another; 1 small spine mesial to anterolateral spine. Rostrum sharply triangular, with 4 moderately incised lateral teeth; dorsal surface flattish, with numerous long setae; length (measured from the tip to level of orbital margin) 0.5 times carapace length, and 1.0–1.3 times width (measured at level of orbital margin); rostral spine and distalmost tooth pair with convex lateral margins.

Abdomen: somites with thick long coarse setae. Somites 2–4 with 2 transverse setiferous ridges each preceded by groove.

Sternum: sternite 3 with anterior margin produced, medially notched, 2.9 times wider than long; sternite 4 twice sternite 3, and 3.1 times wider than long.

Eyes: orbit not laterally produced, unarmed. Eyestalks moderately elongate, twice longer than wide, reaching end of antennal peduncle, proximally somewhat wider, distally with long setae directly proximal to cornea; cornea not swollen, length less than half that of remaining eyestalk.

setosa n. sp., 3.2 mm, SALOMON 1, Stn DW1840 (MNHN-IU- 2010-5262). A, carapace and abdomen, dorsal view; B, sternal plastron, sternites 3 and 4; C, left cephalic region, showing antennular and antennal peduncles, ventral view; D, right Mxp3, lateral view; E, right P1, dorsal view; F, right P2, lateral view; G, right P3, lateral view. Scale: A, B, E–H = 1 mm; C–D = 0.5 mm.

Antennule: article 1 with 3 distal spines: distomesial slender, distolateral well developed, dorsolateral larger than distolateral; 2 slender terminal segments, ultimate segment with tuft of pronounced setae on extensor distal margin.

Antenna: article 1 with ventromesial process ending in acute spine reaching distal end of article 2; article 2 with subequal distomesial and distolateral spines (distomesial spine reaching end of article 3), and additional spine on mesial margin; article 3 with minute distomesial spine.

Mxp3: ischium slightly longer than merus when measured in lateral midline, flexor margin with 2 spines, distal smaller; mesial ridge with 25–27 denticles. Merus with 2 subequal spines on flexor distal margin. Carpus unarmed on flexor margin.

P1: 2.9 times carapace length; very setose dorsally, scarcely setose or nearly glabrous ventrally; long setae mostly plumose, partly coarse. Merus 0.9 times carapace length, with row of spines along lateral, dorsal and mesial sides, mesial spines larger, distal ones prominent. Carpus 1.4 times longer than wide, equally wide as propodus, and 0.8 length of merus; scattered small spines on dorsal side, row of strong spines along mesial margin, small spines on ventral side. Palm 1.4–1.5 times as long as wide; dorsal surface unarmed, with long setae arising from numerous short striae, mesial margin with row of small spines, lateral margin with row of well-developed spines continued on to fixed finger. Fingers 0.8–1.2 times longer than propodus, not gaping and tips crossing when closed; terminating in sharp curved spine; movable finger with proximal spine on mesial margin; fingers unarmed dorsally.

P2–4: P2 about twice carapace length, very setose, setae very long and coarse, often plumose on extensor margin. P2–4 meri posteriorly diminishing in size, extensor margin moderately rounded, lateral side with long setae arising from numerous short striae, and 2 or 3 minute scattered spines; row of proximally diminishing spines on extensor margin, flexor margin with well-developed spines, and 1 extra spine on terminal margin close to distal flexor marginal spine; P2 merus 0.9 times carapace length, 4.0 times longer than wide, and 1.8 times longer than propodus. Carpi with small spines (3 or 4 on P2, 0–2 on P3–4) on extensor margin (distal one larger). Propodi with 4–8 (P2) or 0–5 (P3–4) proximal spines on extensor margin and 7–9 movable slender spines on flexor margin, pair of terminal spines included; P2 propodus 4.5 times longer than wide, and more than 2.5 times dactylus length. Dactyli curved, terminal claw strong, with 2 spines, proximal small.

Distribution. Solomon Islands and New Caledonia, between 80 and 223 m.