Galathea longioculata, 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 : 174-175

Galathea longioculata n. sp.

( Figs 62 , 117 I)

Material examined. Holotype: Vanuatu. SANTO, Stn AT41, 15°36.7–37.0'S, 167°02.7–02.8'E, 88–118 m, 28 September 2006: F 4.8 mm (MNHN-IU-2013-15979).

Paratypes: Vanuatu. SANTO, Stn EP35, 15°34.9–35.1'S, 167°13.9–14.1'E, 10–51 m, 15 October 2006: 2 M 2.1–2.2 mm, 4 ov. F 1.6–2.0 mm (MNHN-IU-2013-15977).

Vanuatu. SANTO. Stn AT41. 1 F 4.8 mm, holotype.

Etymology. From the Latin longus, long, and oculus, eye, in reference to the long eyes.

Description. Carapace: as long as broad; dorsal surface with some short, scale-like transverse ridges with short setae, and some thick and long plumose setae; cervical groove clearly distinct, laterally bifurcated. Epigastric region with 4 small spines and acute tubercles; 2 small parahepatic spines on each side; One strong postcervical spine on each side, 3 well-developed spines on transverse cardiac ridge. Lateral margins slightly convex, with 5 spines: 2 spines in front of and 3 spines behind anterior cervical groove; first anterolateral, well-developed, behind level of lateral limit of orbit; second, small, at midlength between anterolateral spine and anteriormost spine of branchial margin, with spine ventral to between first and second; 3 strong spines on branchial region. Lateral limit of orbit unarmed; infraorbital margin with strong spine. Rostrum 1.6 as long as broad, length 0.5 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 scale-like setose ridges; lateral margin with 4 shallowly incised teeth.

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

Sternum: 1.3 times as long as broad. Sternite 4 broader than sternite 3, and other sternites.

Abdomen: Somites 2–4 each with 2 uninterrupted transverse ridges on tergite; somite 5–6 with 2 scale-like ridges, posteromedian lobe indistinct, straight.

Eyes: Ocular peduncles 2.7 times longer than broad; eyestalk (other than cornea) with lateral margin slightly concave, dorsally with some long plumose setae; cornea not dilated, as broad as the peduncle.

Antennule: Article 1 with 2 well-developed distodorsal and distolateral spines, distodorsal larger; distomesial spine very small; 2 well-developed spines on lateral margin. Ultimate article with a few short fine setae not in tuft on distodorsal margin.

Antenna: Article 1 with distomesial spine nearly reaching distal margin of article 2. Article 2 with 2 welldeveloped distal spines, distolateral spine larger than distomesial and nearly reaching end of article 3. Article 3 with small distomesial spine; article 4 unarmed.

Mxp3: Ischium with well-developed spine on flexor distal margin; extensor margin unarmed; crista dentata with 18 denticles. Merus as long as ischium; flexor margin with 3 blunt protuberances; extensor margin with distal protuberance. Carpus unarmed.

P1 (right missing): 3.6 times carapace length, somewhat depressed on palm, more so on fingers, covered with finely setiferous scales, with numerous long plumose setae. Merus 1.4 times length of carapace, 2.4 times as long as carpus, with some mesial, dorsal and lateral spines, mesial spines stronger; distal spines more prominent. Carpus 0.9 length of palm, 2.4 times as long as broad; dorsal surface with a few small spines, mesial and lateral margins with some spines. Palm 2.8 times as long as broad, lateral and mesial margins slightly divergent; mesial and lateral margins with some prominent ridges. Fingers 0.8 length of palm, each finger distally with two rows of teeth, spooned; fingers unarmed.

P2–4: moderately slender, with setose striae and numerous long thick plumose setae. P2 1.7 times carapace length. Meri successively shorter posteriorly (P3 merus 0.8 length of P2 merus, P4 merus 0.8 length of P3 merus); P2 merus 0.7 carapace length, 3.4 times as long as broad, 1.5 times longer than P2 propodus; P3 merus 2.4 times longer than broad, 1.2 times longer than P3 propodus; P4 merus 2.3 times as long as broad, as long as P4 propodus. Extensor margin of P2–3 meri with row of 5 or 6 proximally diminishing spines, and 5 spines on P4; flexor margins distally ending in strong spine followed proximally by 2 or 3 spines and several eminences; lateral sides unarmed on P2 –3, and with 1 well-developed spine on P4. Carpi with 3 or 4 spines on extensor margin on P2–4; lateral surface with 2 small spines sub-paralleling extensor margin on P2–4; flexor distal margin acute. P2–4 propodi 3.3–4.0 times as long as broad; extensor margin with 3 or 4 proximal spines on P2–4; flexor margin with 4 slender movable spines on P2–4. Dactyli subequal in length, distally ending in well-curved strong spine, length 0.5–0.6 that of propodi; flexor margin with 4 proximally diminishing teeth, terminal one strong.

Epipods absent on pereiopods.

Coloration. Overall translucent whitish, with some scattered red spots on carapace, abdomen and pereopods. Plumose setae on carapace and abdomen reddish; those on pereiopods whitish.

Remarks. Galathea longioculata n. sp. is closely related to G. p a t a e Osawa, 2006, from Ryukyu Islands, Japan. The new species, however, has some strong postcervical and cardiac spines that are absent in G. p a t a e. Furthermore, the spines on the antennal articles are stronger in the new species; and the P2–4 meri are clearly more stouter in the new species than in G. p a t a e, e.g. the P2 merus is 3.4 times as long as broad in G. longioculata versus 5.0 times longer than broad in G. patae .

No genetic data are available for G. longioculata .

Distribution. Vanuatu, 10– 118 m.

Figures

FIGURE 62. Galathea longioculata n. sp., holotype, female, 4.8 mm, Vanuatu (MNHN-IU- 2013 - 15979). A, carapace and abdomen, dorsal view; B, carapace, lateral view; C, sternal plastron; 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, left P 1, dorsal view; G, right P 2, lateral view; H, right P 3, lateral view; I, right P 4, lateral view. Scale: A, B, G, H, I = 1 mm; F = 2 mm; C, D, E = 0.5 mm.

FIGURE 117. Dorsal view. A, Galathea halia n. sp., Vanuatu, ovigerous female 3.2 mm (MNHN-IU- 2013 - 8110). B, Galathea halia n. sp., Vanuatu, ovigerous female 3.2 mm (MNHN-IU- 2013 - 13528). C, Galathea imitata n. sp., Western Australia, ovigerous female 3.2 mm (UF 21915). D, Galathea imitata n. sp., Western Australia, male 3.6 mm (UF 22483). E, Galathea inconspicua Henderson, 1885, Vanuatu, male 5.1 mm (MNHN-IU- 2013 - 8507). F, Galathea inflata Potts, 1915, Papua New Guinea, ovigerous female 6.3 mm (MNHN-IU- 2013 - 509). G, Galathea lemniscata n. sp., New Caledonia, Chesterfield islands, holotype, female 4.8 mm (MNHN-IU- 2013 - 15873). H, Galathea leporis n. sp., Papua New Guinea, male 4.3 mm (MNHN-IU- 2013 - 370). I, Galathea longioculata n. sp., Vanuatu, holotype, female 4.8 mm (MNHN- IU- 2013 - 15979).