Paramunida spica, Cabezas, 2010

Cabezas, P. E., 2010, Taxonomic revision of the genus Paramunida Baba, 1988 (Crustacea: Decapoda: Galatheidae): a morphological and molecular approach, Zootaxa 2712, pp. 1-60 : 44-46

Paramunida spica n. sp.

( Figs. 10, 15D)

Material examined. Holotype: Vanuatu. SANTO, Stn AT 34, 15°35.9'S, 167°17.1'E, 26 September 2006, 234– 270 m: ov. F 7.1 mm (MNHN-Ga7493).

Paratypes: Vanuatu. SANTO, Stn AT 34, 15°35.9'S, 167°17.1'E, 26 September 2006, 234– 270 m: 4 M 5.9–7.8 mm, 7 ov. F 6.2–8.6 mm (MNHN-Ga7494) .

Etymology. The name spica refers to one of the stars from the southern hemisphere (constellation of Virgo).

Description. Carapace: As long as broad. Spinules on gastric and hepatic regions usually not forming groups, lacking scaly striae and with few short uniramous setae. Epigastric region with 2 spines, each behind supraocular spine; with median row of small spines behind rostral spine. Mesogastric region with row of 3 or with row of spines near cardiac region. Frontal margin slightly concave. Some spines and iridescent setae on anterior half of frontal margin. Anterolateral spine small, nearly reaching sinus between rostral and supraocular spines. Rostrum triangular, slightly larger than supraocular spines, with thin dorsal longitudinal carina;

margin between rostral and supraocular spines straight or slightly concave ( Figs. 10A, B).

Sternum: Thoracic sternite 4 with few arcuate striae; sternites 5–7 smooth ( Fig. 10C).

Abdomen: Abdominal somites 2–3 each with 4 well-developed spines on anterior ridge, posterior ridge with 2 median spines. Abdominal somite 4 with 4 small spines on anterior ridge; posterior ridge with distinct median spine ( Fig. 10A).

Eyes: Maximum corneal diameter about one-third distance between bases of anterolateral spines.

abdomen, dorsal view. B, carapace, lateral view. C, sternum. D, left antennule and antenna, ventral view. E, right maxilliped 3, lateral view. F, right P1, merus and carpus, dorsal view. G, right P1, palm and fingers, dorsal view. H, right P2, lateral view. I, right P3, lateral view. J, right P4, lateral view. Scales: A–C, F–J = 1 mm; D–E = 0.5 mm.

Antennule: Segment 1 exceeding corneae, with distomesial spine small and slightly shorter than distolateral; about three times longer than wide and with fringe of long setae along lateral margin; lateral margin of antennular segment 1 with distal slender portion as long as proximal inflated portion ( Fig. 10D).

Antenna: Anterior prolongation of segment 1 clearly overreaching antennular segment 1 by about onefourth of its length. Segment 2 about twice length of segment 3 and twice longer (measured along lateral margin) than wide (measured at midlength of segment), ventral surface with scales; distomesial spine mucronated, overreaching antennal peduncle, overreaching midlength of anterior prolongation of segment 1, distolateral spine nearly reaching midlength of segment 3; segment 3 nearly twice longer than wide and unarmed ( Fig. 10D).

Maxilliped 3: Ischium about twice length of merus measured along dorsal margin, distoventrally bearing one spine; merus with small median spine on flexor margin; extensor margin unarmed ( Fig. 10E).

Pereopod 1: Long and slender, squamate, 4.5–6.3 times carapace length; carpus 0.9–1.0 times palm length, and 7–11 times longer than height; palm 1.4–1.8 times finger length. Base of carpus without bundle of setae ( Fig. 10F).

Pereopods 2–4: Long and slender, with numerous scales on lateral sides of meri, carpi and propodi; scales with short setae. P2 3.2–3.5 times carapace length, merus 1.3–1.4 times longer than carapace, about 12–15 times as long as high, 3.8–4.6 times as long as carpus and 1.7 times as long as propodus; propodus about 9–11 times as long as high, and 1.1–1.3 times dactylus length. Merus with well developed spines on dorsal border, increasing in size distally, ventral margin with few spines and one well-developed distal spine; row of small spines along ventrolateral margins. Carpus with some small dorsal spines, distal spine on dorsal and ventral margin. Propodus with small movable ventral spines. Dactylus compressed, slightly curved, with longitudinal carinae along mesial and lateral sides, ventral border unarmed. End of P2 carpus clearly not reaching end of P1 merus. P3 with similar spination and segment proportions as P2; merus slightly longer than P2 merus; propodus and dactylus slightly longer than those of P2. P4 slightly longer than P2; merus 1.3–1.5 times carapace length; propodus and dactylus slightly longer than those of P3; merocarpal articulation slightly exceeding end of anterior prolongation of segment 1 of antennal peduncle ( Figs. 10G–I).

Remarks. The new species is closely similar to P. belone from New Caledonia, Loyalty Islands, Vanuatu, Tonga, Fiji, Walis and Futuna. The two species can be easily differentiated by the following characters. The mesogastric region has only one (rarely 2) distinct spine in P. belone , whereas there is a row of 3 or 4 moderately-sized spines in P. spica ; the lateral margin of the antennular segment 1 has the distal slender portion as long as the proximal inflated portion in P.spica ; whereas this proximal portion is clearly longer than the distal portion in P. belone . The genetic divergences between P. belone and P. spica were 4.26% (16S rRNA) and 10.85% (ND1).

Distribution. Vanuatu, between 234 and 270 m.