Galathea crinita, Macpherson, Enrique & Robainas-Barcia, Aymee, 2015

Macpherson, Enrique & Robainas-Barcia, Aymee, 2015, Species of the genus Galathea Fabricius, 1793 (Crustacea, Decapoda, Galatheidae) from the Indian and Pacific Oceans, with descriptions of 92 new species, Zootaxa 3913 (1), pp. 1-335 : 94-96

Galathea crinita n. sp.

( Fig. 29 )

Material examined. Holotype: New Caledonia. BATHUS 4, Stn CP912, 18°55.61’S, 163°07.68’E, 690–702 m, 5 August 1994: M 6.0 mm (MNHN-IU-2008-15936).

Paratypes: New Caledonia. Chesterfield Islands. CORAIL 2, Stn DE 16, 20°47.75'S, 160°55.87'E, 500 m, 21 July 1988: 1 ov. F 6.2 mm (MNHN-IU-2013-13981).

New Caledonia. MUSORSTOM 4, Stn CC202, 18°58.00’S, 163°10.50’E, 560 m, 20 September 1985: 1 ov. F 7.2 mm (MNHN-IU-2013-15937).

Etymology. From the Latin crinitus, hairy, in reference to the numerous setae on the body and appendages.

Description. Carapace: As long as broad; transverse ridges with dense short setae, and some long nonplumose and non iridescent setae; cervical groove distinct, laterally bifurcated; most ridges on gastric region interrupted, with numerous scattered scale-like ridges; epigastric region with 8 small spines; 1 or 2 small hepatic and 1 or 2 small parahepatic spines on each side; 5 protogastric and 4 mesogastric small spines; anterior branchial region with scale-like ridges and 3 or 4 small spines. Mid-transverse ridge uninterrupted, with 1 or 2 small spines on each side, preceded by shallow cervical groove, followed by 6 transverse ridges, 1 ridge uninterrupted. Lateral margins slightly convex medially, with 7 spines: 2 spines in front of, and 5 spines behind, anterior cervical groove; first anterolateral, well-developed, slightly behind level of orbit, second small but distinct, located at midlength between first spine and anteriormost spine of branchial margin, with small 1 spine ventral to between first and second; 2 spines on anterior branchial margin, 1 spine ventral to each spine; 3 spines on posterior branchial margin, last small. Small 2 outer orbital spines; infraorbital margin with well-developed spine. Rostrum triangular, 1.7 times as long as broad, length 0.6 that of, breadth 0.3 that of carapace; distance between distalmost lateral incisions 0.25 distance between proximalmost lateral incisions, dorsal surface nearly horizontal in lateral view, with numerous setose scales; lateral margin with 4 deeply incised sharp teeth.

Pterygostomian flap rugose, with sparse short setae, anterior margin bluntly angular.

Sternum: About as long as broad; lateral extremities gently divergent posteriorly.

Abdomen: Somites 2–4 each with 4 uninterrupted transverse ridges on tergite, anterior ridge slightly more elevated than posterior ridges; somites 5 and 6 each with 2 medially interrupted ridges, posteriormedian margin of somite 6 straight. Males with G1 and G2.

Eyes: Ocular peduncles 1.5 times longer than broad, maximum corneal diameter 0.7 rostrum width.

Antennule: Article 1 with 2 well-developed distodorsal and distolateral spines, distodorsal larger; distomesial spine obsolescent. Ultimate article with a few short fine setae on distodorsal margin.

Antenna: Article 1 with distomesial spine barely reaching end of article 2. Article 2 with 2 subequal distal spines, reaching end of article 3. Articles 3 and 4 unarmed.

Mxp3: Ischium with well-developed spine on flexor distal margin; crista dentata with 20 or 21 denticles. Merus slightly shorter than ischium; flexor margin with 3 spines, proximal clearly stronger than median and distal; extensor margin with 1 distinct distal spine. Carpus unarmed.

P1: 3.4 times carapace length, with numerous finely setiferous scales, and some long thick setae. Merus 1.5 times length of carapace; twice as long as carpus, with spines arranged roughly in rows, dorsomesial spines stronger; distal spines prominent. Carpus 0.8 length of palm, 2.3 times as long as broad; dorsal surface with small spines arranged roughly in longitudinal rows; mesial row of well-developed spines. Palm 2.4 times longer than broad, lateral and mesial margins with small spines arranged roughly in dorsolateral and dorsomesial rows, a few small spines scattered on dorsal side. Fingers 0.7 length of palm, each finger distally with two rows of teeth, spooned; mesial margin of movable finger and lateral margin of fixed finger unarmed.

P2–4: Moderately long and slender, with setose striae and long plumose setae. P2 twice carapace length. Meri successively shorter posteriorly (P3 merus 0.8 length of P2 merus, P4 merus 0.8 length of P3 merus); P2 merus 0.8 carapace length, 4.0 times as long as broad, 1.2 times longer than P2 propodus; P3 merus 3.4 times longer than broad, 1.1 times longer than P3 propodus; P4 merus 3.0 times as long as broad, 0.9-1.0 length of P4 propodus. Extensor margins of meri with row of 7 proximally diminishing spines on P2–3, 5 spines on P4; flexor margins distally ending in strong spine followed proximally by 4–6 small spines and several tubercles or eminences; lateral sides with some spines on P2–4. Carpi with 5–7 spines on extensor margin; lateral surface with 4–5 small spines and acute granules sub-paralleling extensor margin on P2–4; flexor distal margin acute. Propodi 5.0–6.0 times as long as broad; extensor margin with 5–7 small proximal spines on P2–4; flexor margin with 6 or 7 slender movable spines on P2–4. Dactyli distally ending in well-curved strong spine, length 0.5 that of propodi; flexor margin with 6 or 7 proximally diminishing teeth, terminal one prominent.

Epipods on P1.

Remarks. Galathea crinita is closely related with G. villosa n. sp. from Madagascar, Mozambique, and Vanuatu (differentiating characters are discussed under Remarks of G. villosa ). The species also resembles G. caesariata n. sp. from Papua New Guinea, Vanuatu and New Caledonia (see above, under Remarks of this species).

Distribution. New Caledonia, Chesterfield Islands, 500– 702 m.

Figures

FIGURE 29. Galathea crinita n. sp., holotype, male, 6.0 mm, New Caledonia (MNHN-IU- 2008 - 15936). A, carapace and abdomen, dorsal view; B, sternal plastron; C, left part of cephalothorax, ventral view, showing antennular and antennal peduncles, and anterior part of pterygostomian flap; D, ischium, merus and carpus of right Mxp 3, lateral view; E, left P 1, dorsal view; F, right P 2, lateral view; G, right P 3, lateral view; H, right P 4, lateral view. Scale: A, F – H = 1 mm; E = 2.0 mm; B – D = 0.5 mm.