Paramunida antares, 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 : 11-13

Paramunida antares n. sp.

( Figs. 2, 12C)

Paramunida luminata Machordom & Macpherson 2004: 262 (table) (not P. luminata Macpherson, 1996 ).

Material examined. Holotype: New Caledonia. NORFOLK 1. Stn DW 1694, 24°40'S, 168°39'E, 24 June 2000, 575– 582 m: M 9.0 mm (MNHN-Ga7470).

Paratypes: New Caledonia. NORFOLK 1. Stn CP 1670, 23°39'S, 167°59'E, 21 June 2000, 382– 384 m: 1 M 5.0 mm, 1 F 9.2 mm (MNHN-Ga7471) .

Etymology. The name antares refers to one of the stars of the southern hemisphere (constellation of Scorpius); used as a noun in apposition.

Description. Carapace: Slightly longer than 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 spines behind rostral spine. Mesogastric region with median Each branchial region with row of spines near cardiac region. Frontal margin slightly concave. Lateral margins convex, with some spines and iridescent setae on anterior half. Anterolateral spine well developed, slightly exceeding 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. 2A, B).

Sternum: Thoracic sternite 4 with few arcuate striae; sternites 5–7 smooth ( Fig. 2C).

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 spines on anterior ridge; posterior ridge with distinct single median spine ( Fig. 2A).

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

Antennule: Segment 1 slightly exceeding corneae, with distomesial spine small and shorter than distolateral; twice longer than wide, with fringe of long setae along lateral margin; lateral margin with distal slender portion about half as long as proximal inflated portion ( Fig. 2D).

Antenna: Anterior prolongation of segment 1 clearly overreaching antennular segment 1 by about onethird of its length. Segment 2 about 1.4 times length of segment 3 and 1.5 times longer than wide, ventral surface with scales; distomesial spine spiniform, reaching end of segment 3, not reaching midlength of anterior prolongation of segment 1, distolateral spine not reaching end of segment 3; segment 3 nearly twice longer than wide and unarmed ( Fig. 2D).

Maxilliped 3: Ischium about twice length of merus measured along dorsal margin, distoventrally bearing long spine; merus with well developed median spine on flexor margin; extensor margin unarmed ( Fig. 2E).

Pereopod 1: Missing chelipeds on type material.

Pereopods 2–4: Long and slender, with numerous scales on lateral sides of meri, carpi and propodi; scales with short setae. P2 3.3 times carapace length, merus 1.5 times longer than carapace, about 12 times as long as high, 4.4 times as long as carpus and 1.7 times as long as propodus; propodus about 9 times as long as high, and 1.6 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 margin. Carpus with some small dorsal spines, distal spine on dorsal and ventral margins. Propodus with some small movable ventral spinules. Dactylus compressed, slightly curved, with longitudinal carinae along mesial and lateral sides, ventral border unarmed. P3 with similar spination and segment proportions than P2; merus as long as P2 merus; propodus and dactylus slightly longer than those of P2. P4 as long as or slightly shorter than P2; merus about 1.4 times carapace length; propodus and dactylus slightly shorter than those of P3; merocarpal articulation clearly exceeding end of anterior prolongation of first segment of antennal peduncle ( Figs. 2F–I).

Remarks. Paramunida antares n. sp. from New Caledonia is very close to P. achernar n. sp. from Tonga. The two species can be distinguished by the following characters:

— The P2–4 propodi are more than 10 times longer than high in P.antares and less than 10 times in P. achernar .

— The merocarpal articulation of P3 clearly exceeds the anterior prolongation of the antennal segment 1 in P. antares , only slightly exceeding the anterior prolongation in P. achernar .

The genetic divergences between P. achernar and P. antares were 3.67% (16S rRNA) and 9.69% (ND1).

The new species is also related to P. luminata from Tuscarora Bank, Wallis Islands, Alofi Bank, Bayonnaise Bank and P. echinata from the French Polynesia (see under Remarks for those species).

The specimens identified as P. luminata by Machordom and Macpherson (2004) belong to the present new

0.5 mm; F–H = 2 mm.