Fennerogalathea cultrata, Rodriguez-Flores, Paula C., Machordom, Annie & Macpherson, Enrique, 2017

Rodriguez-Flores, Paula C., Machordom, Annie & Macpherson, Enrique, 2017, Three new species of squat lobsters of the genus Fennerogalathea Baba, 1988 (Decapoda: Galatheidae) from the Pacific Ocean, Zootaxa 4276 (1) : -

Fennerogalathea cultrata n. sp.

( Figs 4 , 6 C, D)

Material examined. Holotype: Vanuatu, MUSORSTOM 8, Stn CP 1120, 15°07'S, 166°53'E, 282–321 m, 9 October 1994, M 5.8 mm (MNHN-IU-2013-17411).

Paratypes: New Caledonia. East Coast , BATHUS 1. Stn CP 712, 21°43' S, 166°35' E, 210 m, 19 March 1993: 1 F 4.8 mm (MNHN-IU-2013-17418).

New Caledonia. HALIPRO 1. Stn CP 863, 21°31'S, 166°20'E, 190–227 m, 22 March 1994: 1 M 4.6 mm (MNHN-IU-2013-17416).

Vanuatu. MUSORSTOM 8. Stn CP 1077, 16°04'S, 167°06'E, 180–210 m, 5 October 1994: 1 ov F 4.0 mm (MNHN-IU-2013-17419).— Stn CP 1086, 15°36'S, 167°16'E, 185–215 m, 5 October 1994: 1 M 4.2 mm (MNHN- IU-2013-17415).— Stn CP 1103, 15°03'S, 167°07'E, 163–165 m, 7 October 1994: 1 M 5.5 mm (MNHN-IU-2013- 17417).

Vanuatu. SANTO.— Stn AT 22, 15°32.3'S, 167°16.0'E, 180–227 m, 22 September 2006: 1 M 4.1 mm, 1 ov. F 3.7 mm (MNHN-IU-2013-17413).— Stn AT 24, 15°27.5'S, 167°16.2'E, 190–210 m, 23 September 2006: 1 F 4.8 mm (MNHN-IU-2013-17414).— Stn AT 69, 15°40.4'S, 167°17.3'E, 207–229 m, 5 October 2006: 1 M 3.2 mm (MNHN-IU-2013-17412).

Etymology. From the Latin cultratus, knife-shaped, in reference to the shape of the rostrum.

Description. Carapace: 1.3 times longer than broad, dorsally armed with scattered spines and setae and some short transverse ridges; cervical groove distinct. Gastric region indistinctly defined and armed with 3 transverse rows of small spines: anterior row epigastric composed of 4 spines; median row protogastric composed of 6 spines, and posterior row mesogastric composed of 2 spines on a medially interrupted ridge; one additional spine between protogastric and mesogastric rows on each side. Cardiac region with 2 spines distinctly defined. Anterior branchial regions each armed with 1 or 2 spines; 2 postcervical spines on each side. Front margin distinctly oblique; limit of orbit ending in small spine, one small spine between orbit spine and first anterolateral spine; 1 spine on ventral orbital margin. Lateral margins of carapace nearly parallel medially and slightly convex; carapace margin armed with 7 well-developed spines: 2 spines in front and 5 spines behind anterior cervical groove; first spine anterolateral, stronger than second spine, at level of epigastric row of spines; 2 spines on anterior branchial margin and 3 spines on posterior branchial margin; posterior transverse ridge spineless. Rostrum triangular, flattish dorsally, narrow and elongate, 1.6–1.9 longer than broad, 0.4 times of as long as remaining carapace; lateral margin armed with 3 incised teeth; distance between distalmost lateral incisions 0.4 distance between proximalmost lateral incisions.

Sternum: Plastron longer than broad, lateral limits divergent anteriorly. Third thoracic sternite nearly quadrangular, sternite 4 contiguous to entire posterior margin of sternite 3, and wider than sternite 5.

Abdomen: Somite 2 with anterior uninterrupted transverse ridge only on tergite, somites 3 or 4 smooth, with anterior uninterrupted ridge with median tuft of setae; somites 5 and 6 smooth; posteromedian margin on somite 6 straight. Males with G1 and G2.

Eyes: Eyes stalk subcylindrical, narrow and elongate, 0.7 times shorter than rostrum. Ocular peduncles 1.7–2.0 times longer than broad, maximum corneal diameter 0.8 rostrum width.

Antennule: Article 1 with well-developed distolateral and distodorsal spines on, distodorsal slightly overreaching distolateral, distomesial margin with 0–2 minute spines.

Antenna: Article 1 hardly visible from dorsal view, without distinct distomesial spine. Article 2 slightly wider and longer than article 3, with short distolateral and distomesial spines subequal in size. Article 3 with 1 small distomesial and distolateral spine. Article 4 unarmed.

Mxp3: Ischium with well-developed distal spine on flexor margin; extensor margin unarmed; crista dentata with 25 or 26 denticles. Merus subequal in length to ischium, with 3 or 4 spines on flexor margin, proximal longer than others; extensor margin unarmed. Carpus spineless, or with rugosities along extensor margin.

P1: 5.3–5.5 (males), 6.2–6.7 (females) times postorbital carapace length, with some scattered short and long setae on dorsal surface and along lateral and mesial margins of all articles. Merus 2.3–2.5 longer than carapace, 1.8–2.0 times as long as carpus, with numerous spines, stronger spines along mesial and dorsodistal margins. Carpus 0.8–1.0 times as long as palm, 3.6–3.8 (males), 5.2–6.6 times longer than broad, lateral and mesial margins subparallel, dorsal surface with small spines; mesial surface with some strong spines; row of spines along lateral margin. Palm 2.7–3.2 (males), 5.4–6.0 times longer than broad, lateral and mesial margins subparallel; spines arranged in longitudinal dorsolateral and dorsomesial rows. Fingers 0.8–1.0 times palm length, each finger with minute proximal spines, distally with 2 rows of teeth, spooned.

P2–4: Slender, moderately setose, sparsely with long plumose setae on all articles. P2 2.7–2.8 times carapace length. Meri successively shorter posteriorly (P3 merus 0.7–0.8 length of P2 merus, P4 merus 0.8 length of P3 merus); P2 merus 1.1 of carapace length, 10 times as long as broad, 1.3 times longer than P2 propodus; P3 merus 6 times as long as broad, 1.1–1.2 times length of P3 propodus; P4 merus 2.5 times as long as broad, 0.4 length of P4 propodus; extensor margins each with row of 6 or 7 spines in P2–4; lateral surfaces unarmed in P2–3, 2 or 3 minute spines in P4; flexor margins each with strong terminal spine in P2–4, 3–5 additional spines in P2–3, unarmed in P4; ventromesial margins each with 1 or 2 spines in P2. Carpi each with 6–8 spines on extensor margin of P2–4; lateral surfaces each all with row of 2 or 3 small spines paralleling extensor row; flexor margins unarmed or with minute spine. P2–4 propodi 7.5 (P4)–10.5 (P2) times as long as broad; extensor margins each with 5 or 6 small proximal spines in P2–3, unarmed in P4; flexor margins nearly straight, each with 3 pair of terminal spines preceded by 8 or 9 slender movable spines. Dactyli subequal in length, 0.4–0.5 length of propodi, ending in incurved, strong, sharp spine; flexor margins each with prominent triangular terminal tooth preceded by row of 8 or 9 teeth.

Distribution. Vanuatu and New Caledonia, at 163– 321 m.

Remarks. Fennerogalathea cultrata n. sp. is closely related to F. ensifera n. sp. from Fiji (see below). Both species have one small spine on the frontal margin between the lateral orbital spine and the first anterolateral spine of the carapace. However, they can be differentiated by the length and shape of the rostrum (see below). Molecular divergence between F. cultrata n. sp. and F. ensifera n. sp. is 9.43% (COI) and 0.70 % (16S).

Figures

FIGURE 4. Fennerogalathea cultrata n. sp., holotype, male 5.8 mm (MNHN- IU- 2013 - 17411), Vanuatu. A, carapace and abdomen, dorsal view. B, sternal plastron. C, cephalic region, showing antennular and antennal peduncles, ventral view. D, right Mxp 3, lateral view. E, right P 1, dorsal view. F, right P 2, lateral view. G, dactylus of right P 2, lateral view. H, right P 3, lateral view. I, right P 4, lateral view. Scale: A, B, E, F, H, I = 1 mm; C, D, G = 2 mm.

FIGURE 6. Rostrum and right anterior part of cephalothorax, dorsal view, showing eyes and orbit. Fennerogalathea chani n. sp.: A, male 3.4 mm (MNHN-IU- 2013 - 503); B, male 3.6 mm (MNHN IU- 2014 - 13380). Fennerogalathea cultrata n. sp.: C, ovigerous female 4.0 mm (MNHN-IU- 2013 - 17419); D, male 3.2 mm (MNHN-IU- 2013 - 17412). Fennerogalathea ensifera n. sp.: E, ovigerous female 4.9 mm (MNHN-IU- 2013 - 17396); F, male 4.7 mm (MNHN-IU- 2013 - 17398). Scale = 1 mm.