Galathea paleroi, 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 : 207-209

Galathea paleroi n. sp.

( Fig. 74 )

Material examined. Holotype: Vietnam. Gulf of Tonkin, 110 m, 9 February 1960: ov. F 4.0 mm ( OIRAS).

Etymology. This species is dedicated to Ferran Palero of the University of Valencia, for his support in my work and his contributions to crustacean research.

Description. Carapace: As broad as long; transverse ridges with dense short setae, and numerous long and thick iridescent setae; cervical groove distinct, laterally bifurcated. Gastric region with some transverse ridges: 1 epigastric ridge with 2 median spines and medially interrupted, some small scale-like ridges between epigastric and anterior protogastric ridges; 2 protogastric ridges, anterior ridge medially interrupted, without parahepatic spines, posterior ridge scale-like; 1 mesogastric ridge uninterrupted and not extending laterally to anteriormost of branchial marginal spines; 2 metagastric ridges, anterior ridge uninterrupted, not continuing laterally to anteriorbranchial ridge, posterior ridge scale-like. Hepatic region unarmed. Anterior branchial region with distinct ridges. Mid-transverse ridge uninterrupted, preceded by shallow cervical groove. Posterior branchial region with 5 transverse ridges. Lateral margins well convex medially, with 5 spines: 1 spine in front of and 4 spines behind anterior cervical groove; first anterolateral, well-developed, slightly behind of lateral limit of orbit, without spine ventral to between first and cervical groove; 2 spines on anterior branchial region, and 2 spines on posterior branchial margin. Small spine on lateral limit of orbit; infraorbital margin with strong spine and additional acute granules. Rostrum 1.6 times as long as broad, length 0.7 postorbital carapace length and 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 small scale-like setose ridges; lateral margin with 4 deeply incised teeth.

Pterygostomian flap rugose, unarmed, ridges with short setae, anterior margin blunt.

Sternum: As long as broad, lateral extremities gently divergent posteriorly.

Abdomen: Somites 2–4 each with 2 or 3 uninterrupted transverse ridges on tergite; somites 5 and 6 each with 2 medially interrupted ridges, posteromedian margin of somite 6 slightly convex.

Eyes: Ocular peduncles 1.4 times longer than broad, maximum corneal diameter 0.6 rostrum width.

Antennule: Article 1 with 3 well-developed distal spines, distodorsal larger. Ultimate article moderately elongate, twice longer than broad, with a few short fine setae not in tuft on distodorsal margin.

Antenna: Article 1 with ventral distomesial spine not reaching distal margin of article 2. Article 2 with 2 subequal distal spines, and not exceeding midlength of article 3. Article 3 with small distomesial spine. Article 4 unarmed.

Mxp3: Ischium with flexor margins ending in small spine, extensor margin ending in acute angle; crista dentata with 20 denticles. Merus shorter than ischium; flexor margin with 2 spines, proximal spine much longer than distal; extensor margin ending in small spine. Carpus unarmed, extendor border with some prominences.

P1: 2.4 times carapace length, with numerous setiferous scales, and some scattered long setae. Merus 0.8 times carapace length, 1.3 times as long as carpus, with some spines, dorsomesial and distal spines stronger than others. Carpus as long as palm, 2.3 times as long as broad; dorsal surface with some small spines; mesial margin with row of spines, distal second much stronger than others. Palm 1.9 times longer than broad, lateral and mesial margins subparallel; small spines arranged roughly in dorsal, dorsolateral and dorsomesial rows. Fingers as long as palm, unarmed, each finger distally with two rows of teeth, spooned.

P2–4: long and slender, with some setose striae and numerous long iridescent setae. P2 2.1 times carapace length. Meri successively shorter posteriorly (P3 merus 0.8 length of P2 merus, P4 merus 0.7 length of P3 merus); P2 merus 0.8 carapace length, 4.5 times as long as broad, 1.5 times longer than P2 propodus. P3 merus 3.5 times as long as broad, 1.3 times longer than P3 propodus. P4 merus 3 times as long as broad, as long as P4 propodus. Extensor margin with row of 9 or 10 proximally diminishing spines on P2–3, 5 spines on P4; ventral margins distally ending in strong spine, and 2 or 3 eminences, lateral sides unarmed on P2–3, 2 spines on P4. Carpi with 4 or 5 spines on extensor margin on P2–3, 3 or 4 small spines on P4; lateral surface with 3 or 4 spines or acute granules sub-paralleling extensor margin; flexor distal margin acute. Propodi 4.5 times as long as broad; extensor margin unarmed; flexor margin with 4–6 slender movable spines. Dactyli distally ending in well-curved strong spine, length 0.6 that of propodi; flexor margin with 5 or 6 proximally diminishing teeth, terminal one prominent.

Epipods absent on pereiopods.

Remarks. The new species is closely related to G. anepipoda Baba, 1990 , from Madagascar. Both species can be distinsguished by the following aspects:

- The carapace and abdomen have numerous, long and thick, iridescent setae in the new species, whereas these setae are very scarce in G. anepipoda .

- The anterior protogastric ridge is divided into some scale-like ridges, with the median scale moderately long and having numerous long iridescent setae in the new species. This ridge is represented by one short median scale with two long iridescent setae in G. anepipoda .

The specimens from the East China Sea, referred to G. anepipoda by Dong & Li (2010), it might belong to this new species. According to the illustrations provided by these authors, the long setae and transverse ridges on the carapace are less numerous in these specimens than in the new species. In order to establish the specific identity of Dong & Li’s (2010) specimens, direct comparison would be necessary. The material from Sagami Bay, Japan, and Kei Islands ( Baba 2005), and identified as G. anepipoda , could be also related to the new species. Additional material and a more complete comparison is needed to confirm the identity of these occurrences. No genetic data are available from G. paleroi .

Distribution. Vietnam, Gulf of Tonkin, 110 m.

Figures

FIGURE 74. Galathea paleroi n. sp., holotype, ovigerous female, 4.0 mm, Vietnam (OIRAS). A, carapace and abdomen, dorsal view; B, thoracic sternites 3 and 4; C, abdominal somite 6, dorsal view; D, left part of cephalothorax, ventral view, showing antennular and antennal peduncles, and anterior part of pterygostomian flap; E, ischium, merus and carpus of right Mxp 3, lateral view; F, right P 1, dorsal view; G, right P 2, lateral view; H, right P 3, lateral view; I, right P 4, lateral view. Scale: A, C, F, G, H, I = 1 mm; B, D, E = 0.5 mm.