Galathea latirostris Dana, 1852

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 : 155-157

Galathea latirostris Dana, 1852

( Fig. 54 )

Galathea latirostris Dana, 1852: 480 ( Fiji Islands, from coral rock).— Dana, 1855: pl. 30, fig. 8.—Baba et al., 2008: 71 (in part, compilation).

Dubious identifications.

Galathea latirostris Lenz, 1902: 742 (Juan Fernandez Island).— Yokoya, 1933: 57 (Vicinity of Tanabe, E of Kagoshima, coast of Miyazaki, near Omae-zaki, S coast of Atsumi, and between Iki and Goto Islands, 18–190 m).— Boone, 1935: 50, pl. 12 (Ingram Island (Queensland), Samoa, Tahiti (Society Islands), Raiatea Island (Society Islands).— Poupin, 1996: 20 (compilation of French Polynesia records).— Davie, 2002: 61 (no record).

? Galathea cf. latirostris .— Jones & Morgan, 2002: 132, color figure (no record).

Material examined. Fiji. 16°45'S, 179°06'W, 14 May 1965: 1 ov. F 2.7 mm, 1 F 1.6 mm ( ZMUC CRU- 11222).

Description. Carapace: Slightly broader than long; transverse ridges with dense very short setae, without long setae; cervical groove barely distinct. Gastric region with 4 transverse ridges: 1 epigastric ridge medially interrupted, medially convex, unarmed; 1 protogastric uninterrupted ridge, without parahepatic spines; 1 mesogastric ridge uninterrupted and extending laterally to anteriormost of branchial marginal spines; 1 metagastric ridge uninterrupted, not continuing laterally to anteriorbranchial ridges. Hepatic region unarmed. Anterior branchial region with a few distinct ridges. Mid-transverse ridge uninterrupted, preceded by shallow cervical groove. Posterior branchial region with 5 transverse ridges, 2 ridges uninterrupted. Lateral margins slightly convex, with 5 spines: 1 spine in front of and 4 spines behind anterior cervical groove; first anterolateral, well-developed, at same level of lateral limit of orbit, with spine ventral to between first and second spines; 2 spines on anterior branchial region, and 2 spines on posterior branchial margin, last small. Small spine between lateral limit of orbit and anterolateral spine; infraorbital margin with strong spine. Rostrum as long as broad, length 0.6 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 some short setae; lateral margin with 4 shallowly incised sharp teeth.

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

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

Abdomen: Somites 2–4 with 2 uninterrupted ridges; somites 5 and 6 smooth.

Eyes: Ocular peduncles 1.3 times longer than broad, maximum corneal diameter 0.7 rostrum width.

Antennule: Article 1 with 3, distodorsal larger, distomesial spine clearly smaller than others. Ultimate article a few fine setae on distodorsal margin.

Antenna: Article 1 with ventral distomesial spine barely reaching distal margin of article 2. Article 2 with 2 subequal distal spines, reaching midlength of article 3. Article 3 with distomesial spine; article 4 unarmed.

Mxp3: Merus as long as ischium; flexor margin with 2 well-developed spines, distal spine smaller than proximal spine; extensor margin with small distal spine. Carpus unarmed.

P1: 1.7 times carapace length, somewhat depressed on palm, more so on fingers, covered with finely setiferous scales, with scattered long setae. Merus 0.8 times length of carapace, 1.8 times as long as carpus, with some spines arranged roughly in rows, dorsomesial spines stronger; distal spines prominent. Carpus 1.1 length of palm, 1.9 times as long as broad; dorsal and lateral surfaces with some spines; mesial margin with 3 spines (second strong). Palm 1.5 times longer than broad, lateral and mesial margins slightly convex; spines arranged roughly in dorsolateral and dorsomesial rows, dorsal side with some scattered spines. Fingers slightly longer than palm, unarmed; each finger distally with two rows of teeth, spooned.

P2–4: moderately slender, with setose striae and sparse long plumose setae. P2 2.6 times carapace length. Meri successively shorter posteriorly (P3 merus 0.9 length of P2 merus, P4 merus as long as P3 merus); P2 merus 0.7 carapace length, 3.1 times as long as broad, 1.2 times longer than P2 propodus; P3 merus 3.0 times as long as broad, 1.2 times longer than P3 propodus; P4 merus 3.0 times as long as broad, 1.1 times longer than P4 propodus. Extensor margin of P2–3 meri with row of 4 proximally diminishing spines, 3 spines on P4; ventral margins distally ending in strong spine followed proximally by 0–1 spines and several eminences; lateral sides unarmed. Carpi with 2 spines on extensor margin on P2–3, 1 distal spine on P4; lateral surface with 2 small spines or granules sub-paralleling extensor margin; flexor distal margin blunt. P2–4 propodi 3.5–3.7 times as long as broad; extensor margin unarmed; flexor margin with 4 slender movable spines. Dactyli distally ending in well-curved strong spine, length 0.6–0.7 that of propodi; flexor margin with 4 proximally diminishing teeth, terminal one prominent.

Epipods present on P1.

Remarks. The type material of Galathea latirostris was collected from Fiji, but unfortunately it is no longer extant (destroyed by the Great Chicago Fire in 1871, see also Evans 1967). The present two female specimens from Fiji agree quite well with the short description and illustrations provided by Dana (1852, 1855). The closest relative is G. spinimanus Borradaile, 1900 from Lifou, New Caledonia. Unfortunately, additional material of G. spinimanus Borradaile, 1900 was not available for study, and thus sufficient comparison between the two species is not easy. After the illustrations of both species, however, the two species can be easily distinguished by the size of the lateral teeth of the rostrum. These teeth are shallowly incised in G. latirostris , whereas they are deeply incised in G. spinimanus .

No genetic data are available for G. latirostris .

Distribution. Fiji Islands, shallow waters.

Figures

FIGURE 54. Galathea latirostris Dana, 1852, female, 1.6 mm, Fiji (ZMUC CRU- 11222). A, carapace, abdomen, and pereiopods, dorsal view; B, nostrum, dorsal view; C, thoracic sternites 3, 4, and 5; D, left ptrygostomian region; E, left part of cephalothotax, showing antennular and antennal peduncles; F, left Mxp 3, lateral view; G, left P 1, dorsal view; H, P 1 fingers, ventral view: I, right P 3, lateral view; J, right P 4, lateral view. Scales = 1 mm.