Lauriea crucis, 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 : 141-143

Lauriea crucis n. sp.

( Fig. 2 )

Material examined. Holotype: Vanuatu. SANTO, Stn DB16, 15°35.5'S, 167°15.8'E, 32–40 m, 14 September 2006: 1 M 2.1 mm (MNHN-IU-2010-5291).

Paratypes: Vanuatu. SANTO, Stn DB16, 15°35.5'S, 167°15.8'E, 32–40 m, 14 September 2006: 1 ov. F 2.2 mm (MNHN-IU-2010-5259).

Wallis and Futuna. MUSORSTOM 7, Stn CP498, 14°18.9'S, 178°03.1'W, 105–160 m, 10 May 1992: 1 ov. F 2.0 mm (MNHN-IU-2010-5258).

Etymology. The name crucis refers to one of the constellations of the southern hemisphere (Crux, cross).

Description. Carapace: as long as wide, dorsal surface covered with long and short fine setae arising from numerous short transverse ridges; small spines scattered on dorsal surface, 2 largest spines on epigastric region, and 3 or 4 spines along transverse ridge anterior to posterior margin. Cervical groove indistinct. Lateral margins convex, with 7 small but distinct spines on each side, last spine sometimes absent or mesial to lateral margin; first (anterolateral) directly lateral to lateral limit of orbit, remainder more or less distantly separated from one another; 1 small spine mesial to anterolateral spine. Rostrum sharply triangular, with 4 moderately incised teeth, dorsal surface slightly concave, flatish on distal portion, with a few short setae; length (measured from the tip to level of orbital margin) 0.4–0.5 times carapace length, and 0.9 times carapace width (measured at level of orbital margin); rostral spine and distalmost lateral tooth with slightly convex lateral margins.

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

Sternum: sternite 3 with anterior margin medially produced, 3 times wider than long; sternite 4 nearly twice as long as sternite 3, and 4.5 times wider than long.

Eyes: orbit not laterally produced, unarmed. Eyestalks moderately elongate, 1.8 times longer than wide, slightly exceeding antennal peduncle, proximally somewhat wider, distally with long setae directly proximal to cornea; cornea not swollen, length less than that of remaining eyestalk.

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, not exceeding article 2, article 2 with distomesial spine exceeding article 3, distolateral spine reaching end of article 3, additional spine on mesial margin; article 3 unarmed.

Mxp3: ischium as long as merus when measured in lateral midline, flexor margin with short distal spine, mesial ridge with 26–29 denticles. Merus with 2 subequal spines on flexor margin, extensor border unarmed. Carpus with small distal spine on flexor margin.

P1: 2.6–2.7 times carapace length; very setose dorsally, scarcely setose or nearly glabrous ventrally; long setae mostly plumose. Merus 0.8–0.9 times carapace length, with row of spines along lateral, dorsal and mesial sides, mesial spines larger, distal ones strongest. Carpus 1.3–1.4 times longer than wide, more than half length of merus; some scattered spines on dorsal side, row of strong spines along mesial margin, some small spines on ventral side. Palm 1.3–1.5 times as long as wide; dorsal surface unarmed, with some long setae arising from a few short striae, mesial margin with row of spines, lateral margin with row of well-developed spines continued on to fixed finger. Fingers as long as palm, not gaping and tips crossing when closed; terminating in sharp curved spine, dorsal surface unarmed; movable finger unarmed on mesial margin.

P2-4: P2 1.5–1.8 times carapace length, very setose on margins, setae long and coarse, often plumose on extensor margin. P2–4 meri posteriorly diminishing in size, extensor margin sharply ridged, with row of proximally diminishing spines, well-developed spines on flexor margin, and 2 extra spines on terminal margin close to distal flexor marginal spine, lateral side with long setae arising from a few short striae, and 1 or 2 minute spines on P4; P2 merus 0.9 times carapace length, 3.8 times longer than wide, and 2.0–3.0 times longer than propodus. Carpi with small spines (4 on P2–3, 0–1 on P4) on extensor margin (distal one larger). Propodi with very small spines along extensor proximal margin and 4 or 5 movable slender spines on flexor margin, including pair of terminal spines; P2 propodus ca. 4.0 times longer than wide, and 1.9–2.0 times dactylus length. Dactyli sharply biunguiculate, terminal claw strongest.

Remarks. Lauriea crucis n. sp. is closely related to L. teresae n. sp. from French Polynesia (see the differences under the Remarks of L. teresae )

Distribution. Vanuatu, Wallis and Futuna, between 32 and 160 m.

Figures

FIGURE 2. Lauriea crucis n. sp., holotype, male, 2.4 mm, Vanuatu, SANTO, Stn DB 16 (MNHN-IU- 2010 - 5291). 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 Mxp 3, lateral view; E, right P 1, dorsal view; F, right P 2, lateral view; G, right P 3, lateral view; H, right P 4, lateral view. Scale: A, B, E – H = 1 mm; C – D = 0.7 mm.