Galathea boucheti, 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 : 65-67

Galathea boucheti n. sp.

( Figs 17 , 116 A)

Galathea sp.— Poore et al., 2011: 334, pl. 12E (color photo, Vanuatu).

Material examined. Holotype: Madagascar. ATIMO VATAE, Stn TB2, 25°01.3'S, 47° 00.5'E, 18 m, 1 May 2010: 1 M 4.0 mm (MNHN-IU-2013-8110).

Paratypes: Red Sea. Djibouti. Moucha Island, Maskali Bank, 11.6992°N, 43.1432°E, 7–17 m, 27 September 2012: 1 ov. F 3.0 mm (UF32758), 1 M 2.5 mm (UF33346). Saudi Arabia. off Thuwai, Shark reef, 22.4268°N, 38.9963°E, sheltered side, 18 March 2013: 1 M 2.8 mm (UF37106).

Red Sea. Sudan, Al Bahr al Ahmar. Sanganeb, Stn SAN114, 50 m, 25 September 1992: 7 M 1.9–2.6 mm, 1 ov. F 2.5 mm, 4 F 1.6–2.1 mm ( SMF).—Stn SAN123, 20 m, 27 September 1992: 1 M 2.8 mm, 1 ov. F 2.3 mm ( SMF).—Stn SAN139, 30 m, 29 September 1992: 1 M 2.0 mm ( SMF).—Stn SAN125, 14 m, 30 September 1992: 1 M 2.4 mm ( SMF).—Stn SAN107, 10 m, 1 October 1992: 4 M 2.0– 2.5 mm, 6 F 2.0– 2.4 mm ( SMF).—Stn SAN129, 1 m, 1 October 1992: 1 M 2.2 mm ( SMF).—Stn SAN142, 50 m, 1 October 1992: 1 ov. F 2.2 mm ( SMF).—Stn SAN110, 30 m, 2 October 1992: 1 M 2.3 mm ( SMF).—Stn SAN124, 40 m, 2 October 1992: 2 M 3.0– 3.2 mm ( SMF).—Stn SAN120, 6– 10 m, 3 October 1992: 2 M 2.3–2.4 mm, 1 F 2.3 mm ( SMF).—Stn SAN32, 40 m, 2 April 1991: 1 M 3.5 mm ( SMF). Red Sea. Sudan, Al Bahr al Ahmar. Port Sudan, Stn SAN174, 20 m, 19 September 1992: 1 F 2.4 mm ( SMF). Red Sea. Gulf of Aqaba, Marine Science Station, Stn AQ80, 25 m, 14 July 1995: 1 F 3.4 mm ( SMF). Stn AQ103, 8 m, 19 July 1995: 1 M 2.8 mm ( SMF). Saudi Arabia, Al Wajh, 25.3919°N, 36.6839°E, 7 m, 25 September 2013: 1 F 3.0 mm (UF36334), 1 M 2.4 mm (UF36337).—Gulf of Aqaba, 28.4039°N, 34.7407°E, 20 m, 29 September 2013: 1 F 2.0 mm (UF38058).— 28.4039°N, 34.7407°E, 2 m, 30 September 2013: 7 M 1.8–3.1 mm, 3 ov. F 3.3–3.7 mm, 3 F 2.2–2.9 mm (UF38140).— 28.4039°N, 34.7407°E, 60 m, 30 September 2013: 1 M 3.0 mm (UF38158).

Madagascar. BENTHEDI, Stn 14R, 12°22’S, 46°23.7’E, 5–20 m, 21 March 1977: 2 M 2.0– 2.7 mm, 3 F 1.8–2.1 mm (MNHN-IU-2013-8120). ATIMO VATAE, Stn TB2, 25°01.3'S, 47° 00.5'E, 18 m, 1 May 2010: 2 juv. Broken (MNHN-IU- 2010-2737).— Stn CP3572, 25°11.7'S, 47°12.5'E, 75–77 m, 8 May 2010: 1 M 2.5 mm (MNHN-IU-2013-8113).—Stn CP3579, 25°54.5'S, 45°33.2'E, 65–66 m, 9 May 2010: 2 M 2.8–3.3 mm (MNHN- IU-2013-8116).—Stn DW3605, 24°54.5'S, 44°51.0'E, 56–57 m, 13 May 2010: 1 ov. F 2.2 mm (MNHN-IU-2013- 8111), 1 M 3.4 mm (MNHN-IU-2013-8117).— Stn DW3627, 25°29.4'S, 45°45.8'E, 37–38 m, 15 May 2010: 1 M 3.6 mm (MNHN-IU-2013-8115).

South China Sea. Macclesfield Bank, Stn 63, 15°37'2'"N, 114°28'42"E, 63 m, 3 May 1893: 1 M 3.2 mm ( NHMUK). 1 ov. F 3.6 mm ( NHMUK).—Stn 15, 15°37'N, 113°52'E, 67 m, May 1892: 1 M 3.5 mm, 1 F 4.1 mm ( NHMUK).

Vanuatu. SANTO, Stn DB61, 15°32.3'S, 167°16.9'E, 41 m, 25 September 2006: 1 M 2.4 mm (MNHN-IU- 2013-8114), 1 M 2.2 mm (MNHN-IU-2013-8118).—Stn ZB20, 15°36.1'S, 167°05.4'E, 15-20 m, 10 October 2006: 1 F 2.7 mm (MNHN-IU-2013-8119), 1 ov. F 3.0 mm (MNHN-IU-2013-8112).

Etymology. This species is dedicated to Philippe Bouchet of the Muséum nationale d’Histoire Naturelle, Paris, for his enormous support to scientific collection and marine research.

Description. Carapace: As long as broad; cervical groove distinct, but anterior cervical groove indistinct. Gastric region with 7 ridges: 1 epigastric ridge medially interrupted, with 2 submedian spines; 2 protogastric ridges, anterior ridge uninterrupted and medially convex, with 1 parahepatic spine at each side, posterior ridge short and placed medially; 2 mesogastric ridges, anterior ridge uninterruptedly extending laterally to anteriormost of branchial marginal spines, posterior ridge short; 2 metagastric ridges, anterior ridge uninterrupted and extending laterally to anterior branchial ridge. Mid-transverse ridge uninterrupted, preceded by cervical groove, followed by 5 ridges. Lateral margins medially convex, with 6 spines: 1 spine in front of and 5 spines behind anterior cervical groove; first (anterolateral) well-developed, at level of lateral limit of orbit; one small spine ventral to between first anterolateral spine and anteriormost branchial spine; 2 spines on anterior branchial margin, and 3 spines on posterior branchial margin, last small. External limit of orbit ending in small spine; infra-orbital margin with strong spine. Rostrum broadly triangular, 1.3 times as long as broad, 0.5 times of as long as carapace, breadth 0.4 of carapace breadth, distance between distalmost lateral incisions 0.25–0.3 distance between proximalmost lateral incisions, dorsal surface nearly horizontal in lateral view, with some setose scales; lateral margin with 4 deeply incised sharp teeth.

Pterygostomian flap rugose with sparse setae, unarmed, anterior margin spiniform.

Sternum: plastron nearly as long as broad, lateral limits divergent posteriorly.

Abdomen: Somites 2–3 each with 2 uninterrupted transverse ridges on tergite, somite 4 with posterior ridge medially interrupted; somites 5 and 6 each with 2 medially interrupted ridges; posteromedian margin on somite 6 straight. Males with G1 and G2.

Eyes: Ocular peduncles 1.3 times longer than broad, maximum corneal diameter 0.8 rostrum width.

Antennule: Article 1 with 3 well-developed distal spines, distodorsal larger. Ultimate article moderately long, twice longer than broad, with tuft of long setae on distolateral and distomesial margins.

Antenna: Article 1 hardly visible from dorsal view, with depressed distomesial spine reaching distal margin of article 2. Article 2 with distolateral and distomesial subequal, reaching midlength of article 3. Article 3 with small, distinct distomesial 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 2 strong spines on flexor margin, proximal spine located at midlength and clearly larger than distal spine; extensor margin with distal spine. Carpus spineless.

P1: 2.5 times postorbital carapace length, with short and long setae on dorsal surface and along lateral and mesial margins of all articles. Merus as long as carapace, 1.5 times as long as carpus, with numerous spines, stronger spines along mesial and dorsodistal margins. Carpus as long as palm, 1.7 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 1.5 times longer than broad, lateral and mesial margins subparallel; spines arranged in longitudinal rows; dorsolateral row continued onto whole lateral margin of fixed finger. Fingers 0.7 as long as palm, each finger distally with 2 rows of teeth, spooned; movable finger with row of some spines in proximal half of mesial margin, otherwise unarmed.

P2–4: moderately setose, sparsely with long plumose setae on all articles. P2 1.8 times carapace length. Meri successively shorter posteriorly (P3 merus 0.9 length of P2 merus, P4 merus 0.9 length of P3 merus); P2 merus 0.7 of carapace length, 3.4 times as long as broad, 1.4 times longer than P2 propodus; P3 merus 3.2 times as long as broad, 1.3 times length of P3 propodus; P4 merus 3.0 times as long as broad, 1.2 length of P4 propodus; extensor margins each with row of 8-9 proximally diminishing spines in P2–3, unarmed or with 1 or 2 small spines in P4; lateral surfaces unarmed in all P2–4; flexor margins each with strong terminal spine and 1 or 2 additional spines in P2–3, unarmed in P4; ventromesial margins each with terminal spine in P2-4. Carpi each with 4 spines on extensor margin of P2–3, unarmed in P4; lateral surfaces each all with row of 2 or 3 small spines paralleling extensor row; flexor distal margins each with small spine. P2–4 propodi 4 times as long as broad; extensor margins each with 1 or 2 proximal spines in P2–4; flexor margins each with 4 or 5 slender movable spines. Dactyli subequal in length, 0.6–0.7 length of propodi, ending in incurved, strong, sharp spine; flexor margins each with prominent triangular terminal tooth preceded by 4 or 5 low teeth.

Epipods present only on P1.

Coloration. Base color of carapace and abdomen orange. Carapace with some blue spots on gastric region, each branchial region with blue whorl. Abdominal somites with some symmetrically arranged blue spots. P1 orange-reddish, base of fingers bluish. P2–4 with orange and bluish transverse bands or rings.

Remarks. The new species is closely related to G. amamiensis Miyake & Baba, 1966 known from Japan, Indonesia, and Madagascar. Both species have an uninterrupted ridge between the anteriormost branchial marginal spines, the rostrum has 4 deeply incised lateral teeth, 2 epigastric spines on the carapace, and epipods on P1 only. However, G. amamiensis and the new species can be separated by the following aspects:

- The proximal spine on the flexor margin of the Mxp3 merus is clearly larger than the distal spine in the new species, whereas these flexor spines are subequal in G. amamiensis .

- The P2–4 propodi are less than 5 times longer than broad in G. boucheti n. sp., whereas they are more than 5 times in G. amamiensis .

- The color patterns are quite different. The ground color of the carapace and abdomen is yellow-orange with some blue spots and one blue spiral on each branchial region in the new species, whereas the ground color is brownish (without spots), and the rostrum is sometimes reddish in G. amamiensis .

The genetic divergence between G. boucheti and G. amamiensis is 16.6% (COI) ( Tab. 1). Distribution. Red Sea, Madagascar, South China Sea (Macclesfield Bank), Vanuatu, on rocky and coral areas, 2– 77 m.

Figures

FIGURE 17. Galathea boucheti n. sp., holotype, male, 4.0 mm, Madagascar (MNHN-IU- 2013 - 8110). A, carapace and abdomen, dorsal view; B, thoracic sternites 3 and 4; C, left part of cephalothorax, ventral view, showing antennular and antennal peduncles, and anterior part of pterygostomian flap; D, ischium, merus and carpus of right Mxp 3, lateral view; E, right P 1, dorsal view; F, right P 2, lateral view; G, right P 3, lateral view; H, right P 4, lateral view. Scale: A, E – H = 1 mm; B – D = 0.5 mm.

FIGURE 116. Dorsal view. A, Galathea boucheti n. sp., Madagascar, holotype, male 4.0 mm (MNHN-IU- 2013 - 8110). B, Galathea caesariata n. sp., Vanuatu, holotype, male 5.0 mm (MNHN-IU- 2013 - 15938). C, Galathea celiae n. sp., Red Sea, male 2.8 mm (UF 32860). D, Galathea consobrina De Man, 1902, Vanuatu, female 3.2 mm (MNHN-IU- 2013 - 8386). E, Galathea cymo n. sp., Vanuatu, ovigerous female 4.0 mm (MNHN-IU- 2013 - 13343). F, Galathea erythrina n. sp., Red Sea, holotype, female 1.3 mm (UF 36824). G, Galathea eulimene n. sp., Red Sea, Saudi Arabia, male 3.1 mm (UF 35961). H, Galathea galene n. sp., ovigerous female 5.4 mm (MNHN-IU- 2013 - 9878). I, Galathea gladiola n. sp., Vanuatu, holotype, female 4.5 mm (MNHN-IU- 2013 - 8436).