Galathea ternatensis De Man , 1902

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 : 307-310

Galathea ternatensis De Man, 1902

( Figs 109 , 121 E)

Galathea orientalis var. ternatensis De Man, 1902: 714 ( Ternate) .

Dubious identifications:

Galathea ternatensis .— Melin, 1939: 67, figs 39–42 (east of channel between Hahajima and Chichijima, Bonin Islands, 180–210 m).— Miyake & Baba, 1963: 405, fig. 1, 2 (Tomioka, Amakusa, Japan, 20–40 m).— Haig, 1974: 447 (Western Australia).— Baba, 1977a: 245 (Dutch New Guinea and Maldives, 33–46 m).— Baba, 1979a: 525 (Noumea, New Caledonia, 20–23 m).— Baba, 1988: 80 (Sulu Archipelago, Sibuyan Sea north of Cebu, 18–46 m).— Baba, 1989: 130 (Oshima Strait, Amami-oshima, 35 m).—Baba, 1990: 960 ( Madagascar, 25–115 m).— Tirmizi & Javed, 1993: 83, fig. 37 (stn AB43-63, AB-22A, and Mozambique Channel, 62–65 m).— Davie, 2002: 62 (no record).—Baba et al., 2008: 80 (in part, compilation).— Macpherson & Cleva, 2010: 63 , color figs 3I, J ( Madagascar, 24–25 m).— Dong & Li, 2010: 21 , fig. 13 (South China Sea, 21–92 m).— Poore et al., 2011: 334, pl. 12D (color photo, Madagascar).— Osawa & Safaie, 2014: 266 , fig. 1A (North of Lavan Island, Hormozgan Province, Iran, Persian Gulf, 30–50 m).

Material examined. Syntype: Indonesia. Moluccas. Ternate: 3 ov. F 2.8–3.6 mm ( SMF 4560).

Philippines. MUSORSTOM 2, Stn CP47, 13°33'N, 122°10’E, 81–84 m, 26 November 1980: 1 ov. F 3.7 mm (MNHN-IU-2013-13660). MUSORSTOM 3, Stn CP134, 12°01'N, 121°57'E, 92–95 m, 5 June 1985: 2 ov. F 2.8–3.6 mm (MNHN-IU-2013-13672).—Stn CP142, 11°47'N, 123°01’E, 26–27 m, 6 June 1985: 2 M 2.8–4.1 mm (MNHN-IU-2013-13658).

Solomon Islands. SALOMON 1, Stn CP1809, 9°48.385'S, 160°51.193'E, 39–53 m, 3 October 2001: 2 M 3.9–4.5 mm, 2 ov. F 3.1–4.0 mm (MNHN-IU-2013-13659).—Stn CP1810, 9°47.684'S, 160°50.525'E, 53 m, 3 October 2001: 1 M 3.0 mm (MNHN-IU-2013-13656); 6 M 2.8–4.0 mm, 4 ov. F 2.9–3.8 mm (MNHN-IU-2013- 13655); 1 M 2.5 mm (MNHN-IU-2013-13657).

Papua New Guinea. PAPUA NIUGINI, Stn PR25, 05°04.7'S, 145°48.9'E, 7 m, 13 November 2012: 1 M 3.1 mm, 1 ov. F 3.2 mm (MNHN-IU-2013-13665).—Stn PR39, 05°10.2'S, 145°50.3'E, 0 m, 15 November 2012: 1 M 3.5 mm (MNHN-IU-2013-13664); 1 ov. F 3.0 mm (MNHN-IU-2013-497).—Stn PR47, 05°11.2'S, 145°48.4'E, 0 m, 16 November 2012: 7 M 2.0– 2.8 mm, 13 ov. F 2.0–3.0 mm, 2 F 1.8–2.5 mm (MNHN-IU-2013-13662); 1 M 3.0 mm, 1 ov. F 2.3 mm (MNHN-IU-2013-656).—Stn PR53, 05°08.1'S, 145°49.4'E, 20 m, 17 November 2012: 1 F 2.5 mm (MNHN-IU-2013-13666); 1 M 2.5 mm, 2 ov. F 3.0– 3.1 mm (MNHN-IU-2013-13667).— Stn PR78, 05°08'S, 145°49.3'E, 2–32 m, 22 November 2012: 2 M 2.1–2.8 mm, 7 ov. F 2.4–3.0 mm, 3 F 1.8–1.9 mm (MNHN-IU-2013- 13669).—Stn PD49, 05°08.2'S, 145°49.2'E, 2–5 m, 26–27 November 2012: 2 M 2.3–2.7 mm, 2 F 3.0– 3.2 mm (MNHN-IU-2013-13661).—Stn PR143, 05°11.8'S, 145°49.2'E, 23 m, 30 November 2012: 3 ov. F 2.9–3.2 mm (MNHN-IU-2013-13668).—Stn PR155, 05°09.9'S, 145°50.4'E, 1–22 m, 2 December 2012: 1 M 2.3 mm, 1 ov. F 3.0 mm (MNHN-IU-2013-13670).—Stn PR203, 05°10.3'S, 145°48.5'E, 1–19 m, 7 December 2012: 3 ov. F 3.0– 3.2 mm (MNHN-IU-2013-13663).—Stn PR242, 05°10.2'S, 145°50.4'E, 4–24 m, 12 December 2012: 2 ov. F 2.2–2.4 mm, 2 F 2.5–3.3 mm (MNHN-IU-2013-13671).

Description. Carapace: As broad as long; transverse ridges with dense short setae, without long setae; cervical groove distinct, laterally bifurcated. Gastric region with some transverse ridges: 2 epigastric ridges, anterior unarmed, uninterrupted, medially convex, posterior median, short; 2 protogastric ridges, anterior one uninterrupted without parahepatic spines, posterior ridge with some lateral scales; 2 mesogastric ridges, anterior one uninterrupted and not extending laterally to anteriormost of branchial marginal spines, posterior ridge median, short; 2 metagastric ridges, anterior one uninterrupted, continuing laterally to anteriorbranchial ridge, posterior ridge scale-like. Hepatic region with small spine near first lateral (anterolateral) spine. Anterior branchial region with distinct ridges. Mid-transverse ridge uninterrupted, preceded by shallow cervical groove. Posterior branchial region with 5 transverse ridges, 2–4 ridges uninterrupted. Lateral margins slightly convex medially, 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, at midlength between anterolateral spine and anterior cervical groove, without spine ventral to between first and second; 2 spines on anterior branchial region, last small, and 3 spines on posterior branchial margin. Small spine on lateral limit of orbit; infraorbital margin with strong spine. Rostrum 1.8–1.9 times 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 numerous small scale-like setose ridges; lateral margin with 4 deeply incised 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 each with 2 or 3 uninterrupted and 1 or 2 interrupted transverse ridges on tergite; somite 5 with 2 uninterrupted ridges; somite 6 with 2 medially interrupted ridges, posteromedian margin straight. Males with G1 and G2.

Eyes: Ocular peduncles 1.5 times longer than broad, maximum corneal diameter 0.6 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 slightly exceeding distal margin of article 2. Article 2 with 2 distal spines, distolateral spine slightly longer than distomesial, and reaching midlength of article 3. Articles 3 and 4 unarmed.

Mxp3: Ischium with flexor margins ending in small spine, extensor margin ending in blunt angle; crista dentata with 20 or 21 denticles. Merus shorter than ischium; flexor margin with 3 spines, proximal spine slightly longer than others, median spine smaller than distal; extensor margin ending in small spine. Carpus unarmed.

P1: 2.5–3.4 times carapace length, with numerous setiferous scales, and some scattered long setae. Merus 1.2 times carapace length, 1.7–2.7 times as long as carpus, with some spines, dorsomesial and distal spines stronger than others. Carpus 0.8–0.9 length of palm, 2.3–2.7 times as long as broad; dorsal surface with some small spines; mesial margin with row of spines, distal second stronger than others. Palm 2.4–2.7 times longer than broad, lateral and mesial margins subparallel; small spines arranged roughly in dorsal, dorsolateral and dorsomesial rows. Fingers 0.7–1.0 times palm length, each finger with two rows of teeth distally spooned; fingers unarmed.

P2–4: long and slender, with some setose striae and sparse long plumose and non-plumose setae. P2 1.9–2.0 times carapace length. Meri successively shorter posteriorly (P3 merus 0.8–0.9 length of P2 merus, P4 merus 0.7 length of P3 merus); P2 merus 0.8 carapace length, 4.6–4.7 times as long as broad, 1.2–1.4 times longer than P2 propodus. P3 merus 4.0 times as long as broad, 1.2 times longer than P3 propodus. P4 merus 3.3 times as long as broad, as long as P4 propodus. Extensor margin with row of 8–11 proximally diminishing spines on P2–3, 1 or 2 spines on P4; ventral margins distally ending in strong spine, lateral sides with 2or 3 spines on P4 only. Carpi with 2–5 spines on extensor margin on P2–3, 1 small distal spine on P4; lateral surface with 3 or 4 acute granules subparalleling extensor margin; flexor distal margin acute. Propodi 4.5–6.0 times as long as broad; extensor margin with 0–2 minute proximal spines; flexor margin with 4 or 5 slender movable spines. Dactyli distally ending in wellcurved strong spine, length 0.5–0.6 that of propodi; flexor margin with 5 or 6 proximally diminishing teeth, terminal one prominent.

Epipods present on P1.

Coloration. Base color light orange. Numerous small red and white spots scattered on carapace and abdomen; ridges reddish; carapace spines whitish. P1 with white distal stripe on palm; spines whitish. P2–4 with distal white band on merus and propodus.

Remarks. Galathea ternatensis is characterized by the following features: an interrupted the mesogastric ridge is interrupted; epigastric spines are absent; the gastric ridges are not scale-like; the carapace lateral margin has one small but distinct spine between the anterolateral spine and the anteriormost spine on the branchial margin; the antennular basal article has three well-developed terminal spines; and epipodis present only on P1. These characters are shared with other related species: G. boisselierae n. sp., G. eione n. sp., G. melobosis n. sp., G. patriciae n. sp., G. providentia Laurie, 1926 , and G. ternatensis, 1902 . Galathea ternatensis and G. melobosis are easily differentiated from the other four species by the anterior metagastric ridge, continuing laterally to the anterior branchial ridges in G. ternatensis and G. melobosis , and not continuing laterally in the other species. The genetic divergence among G. ternatensis and G. boisselierae , G. eione , and G. providentia are larger than 16.7% (COI) and 6.3% (16S rRNA) ( Tab. 2 ).

Galathea ternatensis can be differentiated from G. melobosis by the number of transverse ridges on the abdominal somites. There are four ridges in G. ternatensis and two in G. melobosis . The genetic divergence between the two species is 16.6% (COI) and 5.8% (16S rRNA) ( Tab. 2 ).

The existence of some new species, closely related with G. ternatensis , recommends a careful study of the material previously identified as G. ternatensis (see above, dubious identifications). Unfortunately, we have only revised a small portion of these specimens and we can’t identified them accurately with the information provided by the authors. A similar problem exists with the material identified as G. providentia .

Distribution. Indonesia ( Moluccas, Ternate), Philippines, Papua New Guinea, Solomon Islands; 0– 95 m.

Figures

FIGURE 109. Galathea ternatensis De Man, 1902, syntype, ovigerous female, 3.3 mm, Indonesia, Moluccas (SMF 4560). 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 left Mxp 3, lateral view (setae not figured). Scale: A = 1 mm; B – D = 0.5 mm.

FIGURE 121. Dorsal view. A, Galathea subsquamata Stimpson, 1858, Papua New Guinea, male 3.4 mm (MNHN-IU- 2013 - 353). B, Galathea tagaloa n. sp., Vanuatu, M 6.5 mm (MNHN-IU- 2013 - 13983). C, Galathea tagaro n. sp., Vanuatu, holotype, female 4.7 mm (MNHN-IU- 2013 - 8365). D, Galathea tanegashimae Baba, 1969, Papua New Guinea, male 2.3 mm (MNHN- IU- 2013 - 375). E, Galathea ternatensis De Man, 1902, Papua New Guinea, male 3.5 mm (MNHN-IU- 2013 - 13664). F, Galathea tongi n. sp., French Polynesia, ovigerous female 3.0 mm (UF 15686).