Galathea eulimene, 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 : 111-114

Galathea eulimene n. sp.

( Figs 36 , 116 G)

Galathea spinosorostris . — Laurie, 1926: 124 (Providence, Seychelles, Amirante, Saya de Malha Bank, Cargados Carajos, Chagos, 13–81 m).—Baba, 1990: 959 ( Madagascar, 14–340 m).— Tirmizi & Javed, 1993: 59, fig. 26 (Andaman Sea and N Madagascar, 1.5–772 m).— Macpherson & Cleva, 2010: 62, color fig 3F ( La Réunion, Mayotte, 10–30 m). Galathea longimana .— Lewinsohn, 1969: 107, fig. 20 (Red Sea, 0–3 m).

Dubious identifications:

Galathea spinosorostris .— Miers, 1884: 560 (Marie-Louise des Neufs, and Providence Islands, 27–35 m).— Tirmizi, 1966: 181, figs 4B, 5 ( Zanzibar, 73–165 m).— Lewinsohn, 1969: 110 (no record).— Lewinsohn, 1981: 184 (compilation). Galathea algae . — Baba, 1977a: 248 (Obi latoe, Ternate, and Seychelles, 0–4 m).

Material examined. Holotype: Scattered Islands. Glorieuses, 11.5813°S, 47.3413°E, 13–14 m, 8 May 2009: M 3.2 mm (UF21038).

Paratypes: Red Sea. Sudan, Al Bahr al Ahmar. Sanganeb, SAN31, 70 m, 1 July 1991: 1 juv. 1.8 mm ( SMF).

Red Sea. Gulf of Aqaba, Ferry Port, 5 m, 12 July 1995: 1 M 3.0 mm, 1 F 2.6 mm ( SMF).— 5–10 m, 22 July 1995: 1 M 3.4 mm, 1 ov. F 3.0 mm ( SMF). Marine Science Station, AQ44, 5 m, 9 July 1995: 1 ov. F 2.6 mm ( SMF).—AQ55, 13 m, 11 July 1995: 1 ov. F 2.7 mm, 2 F 2.5–2.6 mm ( SMF).— 8 m, 19 July 1995: 1 F 2.7 mm ( SMF). Sudan, Al Bahr al Ahmar. Sanganeb, SAN17, 20 m, 29 March 1991: 1 F 2.0 mm ( SMF).—SAN21, 20 m, 29 March 1991: 2 M 2.2–2.6 mm, 1 ov. F 3.0 mm ( SMF).—SANGANEB, 0 m, 29 March 1991: 1 M 1.8 mm ( SMF).—SAN33, 20 m, 30 March 1991: 2 M 2.6–3.0 mm, 1 ov. F 3.0 mm, 1 F 2.4 mm ( SMF).—SAN51, 1 m, 30 March 1991: 1 M 2.7 mm, 1 F 2.8 mm ( SMF). SAN52, 12 m, 1 April 1991: 3 M 2.6–3.0 mm, 1 ov. F 2.8 mm, 1 F 3.0 mm ( SMF).—SAN42, 12 m, 2 April 1991: 3 M 2.2–2.5 mm, 1 ov. F 3.1 mm, 1 F 2.4 mm ( SMF).—SAN34, 13 m, 3 April 1991: 1 F 2.4 mm ( SMF).—SAN1, 15 m, 4 April 1991: 2 F 2.0– 2.1 mm ( SMF).—SAN25, 11 m, 8 April 1991: 3 M 2.0– 2.5 mm, 1 ov. F 3.1 mm, 2 F 2.0– 2.1 mm ( SMF).—SAN26, 12 m, 9 April 1991: 2 M 2.5–3.2 mm ( SMF).—SAN45, no depth, 15 April 1991: 4 M 2.4–2.8 mm, 3 ov. F 2.3–2.7 mm ( SMF).—SAN170, 20 September 1992: 1 M 2.6 mm ( SMF).—SAN114, 50 m, 25 September 1992: 6 M 1.8–2.4 mm, 1 ov. F 2.5 mm, 4 F 1.6–2.4 mm ( SMF).—SAN128, 30 m, 26 September 1992: 1 M 1.8 mm ( SMF).—SAN117, 14 m, 27 September 1992: 3 M 2.3–2.6 mm, 2 ov. F 2.2–2.6 mm, 2 F 2.0– 2.2 mm ( SMF).—SAN113, 30 m, 27 September 1992: 2 M 2.1–2.6 mm, 1 ov. F 2.5 mm, 1 F 2.0 mm ( SMF).—SAN135, 10 m, 28 September 1992: 1 F 2.1 mm ( SMF).—SAN111, 6 m, 29 September 1992: 1 M 1.8 mm ( SMF).—SAN118, 12 m, 29 September 1992: 10 M 2.4–3.4 mm, 4 ov. F 3.1–3.5 mm, 2 F 2.5–2.6 mm ( SMF).—SAN139, 30 m, 29 September 1992: 2 ov. F 2.3–2.4 mm ( SMF).—SAN125, 14 m, 30 September 1992: 11 M 1.6–2.1 mm, 9 F 1.4–2.2 mm ( SMF).—SAN144, 8 m, 1 October 1992: 3 M 2.1–2.6 mm, 2 F 2.0– 2.3 mm ( SMF).—SAN146, 6- 10 m, 1 October 1992: 1 M 3.2 mm ( SMF).—SAN105, 1 m, 2 October 1992: 5 M 2.1–2.5 mm, 1 ov. F 2.3 mm, 1 F 2.1 mm ( SMF).—SAN110, 31 m, 2 October 1992: 2 M 2.0– 2.2 mm, 1 ov. F 2.1 mm ( SMF).—SAN124, 41 m, 2 October 1992: 1 ov. F 2.8 mm ( SMF).—SAN106, 6– 10 m, 3 October 1992: 2 M 3.0– 3.2 mm, 2 ov. F 2.9–3.1 mm, 3 F 2.8–3.2 mm ( SMF).—SAN47, no depth, 1991: 4 M 2.1–2.4 mm, 3 ov. F 2.5–2.8 mm, 4 F 2.0– 2.3 mm ( SMF). Port Sudan, Wingate Reef. SAN166, 5 m, 21 September 1992: 2 ov. F 2.3–2.5 mm ( SMF).—SAN169, 4 m, 22 September 1992: 4 M 2.0– 2.8 mm, 1 ov. F 2.4 mm, 1 F 2.2 mm ( SMF). Red Sea. Djibouti. Gulf of Tadjoura, 11.5515°N, 42.7006°E, 1-8 m, 29 September 2012: 1 F 3.4 mm (UF32841). Red Sea. Saudi Arabia. Thuwai. Al-Fahal reef, 1–37 m, 8 October 2012: 1 F 2.1 mm (UF33083).— 22.2741°N, 39.0512°E, 5 m, 10 October 2012: 2 M 1.7–2.2 mm (UF33063).—Shark reef, 22.4268°N, 38.9963°E, 18 March 2013: 1 M 1.9 mm (UF36029); 1 M 4.1 mm (UF36057); 1 ov. F 3.3 mm (UF37112); 2 M 1.7–2.8 mm (UF37130).— 22.2227°N, 38.9677°E, exposed side of reef, 19 March 2013: 1 ov. F 2.8 mm (UF37135); 1 ov. F 2.5 mm (UF37136).—Abu Shosha Reef, 22.2044°N, 39.047°E, 7–8 m, 23 March 2013: 1 M 1.9 mm (UF37403). Farasan Banks, Pelican Island, 18.6595°N, 40.827°E, 1–2 m, 5 March 2013: 1 ov. F 2.0 mm (UF36540); 1 M 2.2 mm (UF36551).—Farasan Banks, Dolphen Lagoon, 19.0053°N, 40.1482°E, 1–7 m, 4 March 2013: 1 ov. F 2.4 mm (UF36589); 1 ov. F 2.3 mm (UF36604). Shib Radib, 18.0731°N, 40.8859°E, 7–9 m, 8 March 2013: 1 F 3.3 mm (UF36735); 5 M 2.4–3.2 mm, 4 ov. F 2.6–3.9 mm, 1 F 1.8 mm (UF36821). Marca Is., 18.0731°N, 40.8859°E, 7–9 m, 8 March 2013: 1 M 2.7 mm (UF36820). Shi'b Ammar, 19.5707°N, 40.0088°E, 2–20 m, 3 March 2013: 1 M 3.1 mm (UF35961). Red Sea. Al Lith, 20°15.554'N, 39°56'E, 4–5 m, 8 March 2012: 4 M 2.3–3.2 mm, 1 ov. F 2.4 mm ( SMF). Red Sea. Saudi Arabia, Al Wajh, 25.3919°N, 36.6839°N, 10-30 m, 25 September 2013: 1 ov. F 3.0 mm (UF36349), 2 M 2.7-3.6 mm, 1 ov. F 2.0 mm, 1 F 2.0 mm (UF36350), 1 ov. F 3.0 mm (UF36360). Jaz'air, 27.6384°N, 35.3062°E, 10 m, 27 September 2013: 1 M 2.7 mm, 1 ov. F 3.4 mm (UF36438). Gulf of Aqaba, 28.4039°N, 34.7407°E, 10 m, 29 September 2013: 1 ov. F 2.9 mm (UF38054), 1 ov. F 2.2 mm (UF38067).— 28.4039°N, 34.7407°E, 20 m, 29 September 2013: 1 F 1.8 mm (UF38088).— 28.4039°N, 34.7407°E, 20–25 m, 30 September 2013: 4 M 2.0– 2.4 mm, 1 ov. F 2.2 mm, 3 F 1.8–2.0 mm (UF38101). Yanbu, 24.4427°N, 37.2477'E, 3–22 m, 4 October 2013: 1 ov. F 2.3 mm (UF38289).

Seychelles Islands. Aldabra Island. 42 m, 23 May 1954: 2 ov. F 2.5-2.7 mm (MNHN-Ga775, 771, MNHN-IU- 2013-14277).

Comore Island. BENTHEDI, Stn 32R, 12°45.1'S, 45°17.9'E, 15–20 m, 25 March 1977: 3 M 1.7–2.1 mm, 3 F 1.6–2.0 mm (MNHN-IU-2013-13967). Mayotte Island, 12.7605°S, 45.068°E, 3 m, 30 May 2008: 1 ov. F 3.4 mm (UF13580).— 12.8551°S, 45.2686°E, 6–9 m, 2 June 2008: 1 M 3.0 mm (UF13653).

Scattered Islands. Glorieuses, 11.5909°S, 47.2851°E, 7–14 m, 4 May 2009: 1 M 2.0 mm (UF21177); 1 ov. F 3.2 mm (UF21282).— 11.5916°S, 47.2853°E, 17 m, 5 May 2009: 1 M 2.5 mm (UF21270).

La Reunion. Pierre au Prefet, 10–19 m, 21.0625°S, 55.2128°E, 15 August 2007: 1 M 3.0 mm (UF12841).

Maldives Islands. Dhign Reef, 3.0803°N, 72.9827°E, 5 m, 13 May 2014: 1 ov. F 2.9 mm (UF39661), 1 ov. F 2.2 mm (UF39662). Magoodhoo Island, 3.077°N, 72.969°E, 12 m, 14 May 2014: 2 F 2.5–3.2 mm (UF39677), 1 M 2.7 mm (UF39703).

Chagos Islands. Diego Garcia, 8–12 m, February 2012: 10 F 1.3–1.5 mm ( OUMNH). Solomon, 8–12 m, February 2012: 4 M 1.8–3.5 mm, 3 ov F 2.4–4.2 mm, 15 F 1.4–2.5 mm ( OUMNH). Peros Banhos, 8–12 m, February 2012: 15 M 1.3–3.7 mm, 5 ov F 1.5–2.7 mm, 7 F 1.3–2.8 mm ( OUMNH). Great Chagos Bank, Brothers Island, 8–12 m, February 2012: 3 M 1.6–2.4 mm, 2 ov. F 3.3–3.6 mm, 4 F 1.2–2.3 mm ( OUMNH). Great Chagos Bank, Eagle Island, 8–12 m, February 2012: 1 ov F 2.8 mm, 12 F 1.2–2.0 mm ( OUMNH). Egmont Island, 8–12 m, February 2012: 6 M 1.5–3.6 mm, 8 F 1.3–1.5 mm ( OUMNH).

Etymology. The name Eulimene , good haven, refers to one of the Nereids of Greek mythology. The name is considered as a substantive in apposition.

Description. Carapace: slightly broader than long; transverse ridges with dense very short setae, and a few scattered long plumose setae; cervical groove distinct, laterally bifurcated. Gastric region with 5 transverse ridges: 1 epigastric ridge medially interrupted, with 2 median spines; 2 mesogastric ridges, anterior medially uninterrupted (interrupted in some paratypes), posterior ridge scale-like; 2 scale-like metagastric ridges. One or two small parahepatic spines, and one hepatic spine, near anterolateral spine, on each side. Anterior branchial region with distinct ridges. Mid-transverse ridge uninterrupted, preceded by shallow cervical groove, followed by 4 ridges, 2 of them uninterrupted. Lateral margins slightly convex, with 7 spines: 2 spines in front of, and 5 spines behind, anterior cervical groove; first anterolateral, well-developed, at same level of lateral limit of orbit, second small, with spine ventral to between first and second spines; 2 spines on anterior branchial region, and 3 spines on posterior branchial margin, last small. Small spine on lateral limit of orbit; infraorbital margin with strong spine. Rostrum 1.2 as long as broad, length 0.6 postorbital carapace length and breadth 0.4 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 deeply 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 transverse uninterrupted ridges; somites 5 and 6 smooth; somite 6 with posteriomedian margin straight. Males with G1 and G2.

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

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

Antenna: Article 1 with ventral distomesial spine exceeding 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: Ischium with small spine on flexor and extensor distal margins; crista dentata with 20 or 21 denticles. Merus as long as ischium; flexor margin with 2 subequal well-developed spines; extensor margin with distal spine and 0–2 small additional spines. Carpus with 0–3 acute granules or spines along dorsal extensor margin.

P1: 2.5–3.0 times carapace length, covered with finely setiferous scales, with scattered long simple setae. Merus as long as carapace, 1.7 times as long as carpus, with spines arranged roughly in rows, dorsomesial spines stronger; distal spines prominent. Carpus as long as palm, twice longer than broad; dorsal and lateral surfaces with some spines; mesial margin with 5 spines (distal second strong). Palm twice longer than broad, lateral and mesial margins subparallel; spines arranged roughly in dorsolateral and dorsomesial rows; dorsolateral row continuing along entire fixed finger; row of spines along dorsal side. Fingers as long as palm, each finger with two rows of teeth distally spooned; movable finger unarmed.

P2–4: moderately slender, with setose striae and sparse long plumose setae. P2 2.1 times carapace length. Meri successively shorter posteriorly (P3 merus 0.9 length of P3 merus, P4 merus 0.8 length of P2 merus); P2 merus as long as carapace, 4.0 times as long as broad, 1.5 times longer than P2 propodus; P3 merus 3.2 times as long as broad, 1.3 times longer than P3 propodus; P4 merus 2.7 times as long as broad, as long as P2 propodus. Extensor margin of P2–3 meri with row of 8 or 9 proximally diminishing spines, 2 or 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 5 or 6 spines on extensor margin on P2–3, 0–3 spines on P4; lateral surface with 3 or 4 small spines or acute granules sub-paralleling extensor margin; flexor distal margin acute. P2–4 propodi 5.0 times as long as broad; extensor margin with 3 or 4 proximal spines on P2–4; flexor margin with 4 slender movable spines (6 in P 2 in only one specimen). Dactyli distally ending in well-curved strong spine, length 0.5 that of propodi; flexor margin with 4 proximally diminishing teeth, terminal one prominent.

Epipods present only on P1.

Coloration. Translucent reddish brown or whitish overall. Numerous minute red spots on carapace and abdomen. Carapace sometimes, with one greenish spot on each side of mid-transverse ridge. Abdominal somites 2–4 each with some white spots. P1 with reddish stripe on distal portion of merus, carpus, palm and proximal half of fingers; white stripe on median portion of palm and distal half of fingers; spines red. P2–4 with reddish band on distal part of merus, carpus and median part of propodus; white band on distal part of fingers.

Remarks. The new species is very close to G. algae Baba, 1969 . However, both species can be differentiated by the relative length of the articles of the walking legs. The P2–4 propodi are 3–4 times longer than broad in G. algae , instead of five times longer than broad in G. e u l i m e n e.

Galathea eulimene also resembles G. cephyra n. sp. from New Caledonia and G. spinosorostris Dana, 1852 from Hawaii and French Polynesia (see also Remarks of these species).

Distribution. Red Sea, Seychelles Islands, Scattered Islands, Comore Island, La Reunion, Maldive Islands, Chagos Islands; 0–50 m, on Pocillopora spp., Acropora spp., Stylophora spp., rocks.

Figures

FIGURE 36. Galathea eulimene n. sp., holotype, male, 3.2 mm, Scattered Islands (UF 21038). A, carapace and abdomen, dorsal view; B, sternal plastron; 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, abdominal somite 6, dorsal 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).