Galearctus kitanoviriosus ( Harada, 1962 ) Holthuis, 2002

Holthuis, Lipke B., 2002, The Indo-Pacific scyllarine lobsters (Crustacea, Decapoda, Scyllaridae), Zoosystema 24 (3), pp. 499-683 : 565-571

Galearctus kitanoviriosus ( Harada, 1962) n. comb.

( Fig. 25 )

Scyllarus kitanoviriosus Harada, 1962: 120 , text-figs 6, 7, pl. 9, pl. 12 fig. 14, pl. 13 fig. 18; 1965: 36, fig. 1c- d; 1968: 82. — Nishimura & Suzuki 1971: 89, pl. 30 fig. 5. — Kim & Park 1972: 210, pl. 6 figs 5, 6. — Motoh 1972: 48, pl. 15 figs 1, 2. — Kim 1976: 147; 1977: 339, 400, text-figs 152, 153, pl. 36 fig. 75. — Matsuzawa 1977: pl. 75 fig. 1. — Suzuki 1979: 295, pl. 18 fig. 232. — Phillips et al. 1980: 70. — Miyake 1982: 84. — Higa & Saisho 1983: 86, figs. — Chan & Yu 1986: 158, pl. 6, pl. 10 fig. A; 1993: 209, col. fig. — Sekiguchi 1986a: 1289-1291; 1986b: 15, 17; 1986c: 293; 1987a: 331; 1987b: 417, 418; 1988: 3; 1990a: 113. — Sakaji & Tokai 1992: 97, figs 1-7. — Huang 1994: 564. — Fransen et al. 1998: 67. — Wang et al. 1998: 446, 448, fig. 2. — Debelius 1999a: 224, col. fig.; 1999b: 224, col. fig.; 2000: 224, col. fig. — Motoh 1999: 38, 2 col. figs. — Minemizu et al. 2000: 124, col. fig.

TYPE MATERIAL. — Holotype: (Misaki Park Aquarium); paratypes: 1 36 mm ( RMNH D 30923); 1 and 2 (Seto Marine Biological Laboratory), see paragraph Distribution.

TYPE LOCALITY. — Japan. Saikasaki, Kitan Channel, entrance of Osaka Bay.

MATERIAL EXAMINED. — Japan. Saikasaki, Kitan Channel, entrance of Osaka Bay from gill net, spring 1961, E. Harada don., 1 paratype 36 mm ( RMNH D 30923).

Off Yoshimi, Shimonoseki, Yamaguchi prefecture, K. Kataoka leg., K. I. Hayashi don., 1 28 mm ( RMNH D 38508).

Off Ushibuka, Kumamoto Prefecture, Kyushu, 15.VI.1983, N. Koike leg., K. I. Hayashi don., 1 30 mm ( RMNH D 38510).

Taiwan. NE coast, Peace Id, Keelung, about 100 m deep, bottom gill net, V.1997, T. Y. Chan leg., 2 ( RMNH D 49568).

Chesterfield Islands. Dredge, 250 m, 22.V.1979, 1, 28 mm (MNHN-Pa 1046).

New Caledonia. North New Caledonia. HALICAL 1, stn 2, 20°47.5’S, 164°52’E, 658-680 m, 23.XI.1994, 1 13 mm (badly damaged, part of carapace missing) (MNHN-Pa 1860).

East New Caledonia. HALIPRO 1, stn CP 851, 21°43’S, 166°37’E, 314-364 m, 19.III.1994, 1 11 mm (MNHN-Pa 1861).

BATHUS 1, stn CP 711, 21°43.16’S, 166°36.35’E, 315-327 m, 13.III.1993, 1 juv. 9 mm (MNHN-Pa 1859).

South-West New Caledonia. S îlot Ua, RV Vauban, stn 248, 22°30.75’S, 166°46.20’E, 25.XI.1978, A. Intès, 1 ov. 23 mm (MNHN-Pa 775).

Norfolk Ridge. SMIB 3, stn DW 14, 23°40’S, 168°00’E, 246 m, 22.V.1987, 1 26 mm (MNHN- Pa 1274).

BERYX 11, stn CP 22, 24°44’S, 168°07’E, 490- 510 m, 17.X.1992, 1 ov. 31 mm (MNHN-Pa 1862). — Stn CP 23, 24°43’S, 168°08’E, 270-290 m, 17.X.1992, 1 ov. 23 mm ( USNM 1000666). — Stn CP 26, 24°42’S, 168°08’E, 230-260 m, 17.X.1992, 1 ov. 26 mm ( MNHN).

LITHIST, stn CP 17, Banc Jumeau Ouest, 23°40.8’S, 168°00.8’E, 247-281 m, 12.VIII.1999, 1 ov.

25 mm ( RMNH D 48746).

Matthew Id. VOLSMAR, stn DW 39, 22°20.5’S, 168°43.5’E, 305 m, 8.VI.1989, 1 26 mm (MNHN-Pa 1384).

Fiji Islands. BORDAU 1, stn CP 1474, 19°39’S, 178°10’W, 316-340 m, 8.III.1999, 1 11 mm, 1 10 mm (MNHN-Pa 1913). — Stn CP 1501, 18°40’S, 178°30’W, 350-357 m, 12.III.1999, 1 juv. 7 mm (MNHN-Pa 1914).

DISTRIBUTION. — The type locality of the species is Saikasaki, Kitan Channel, entrance of Osaka Bay, Honshu, Japan. The other records in the literature all pertain to Korean, Japanese and Taiwanese material.

Korea: off Haeundae, Korea Strait, SE Korea ( Kim 1976, 1977), Seogwipo, Jeju Id (= Cheju Id, = Quelpart Id), Korea Strait ( Kim & Park 1972; Kim 1977).

Japan ( Nishimura & Suzuki 1971; Phillips et al. 1980; Miyake 1982; Sekiguchi 1986a, b, c, 1987a, b, 1988, 1989a, 1990a; Motoh 1999; Minemizu et al. 2000). Sea of Japan, west coast of Honshu: Yamagata Prefecture ( Suzuki 1979), off Nozaki, east coast of Noto Id, Toyama Bay ( Motoh 1972), Mihonoseki, Miho Bay ( Harada 1962, 1968). South coast of Honshu: Izu Peninsula ( Debelius 1999a, b, 2000), Kii District ( Harada 1965), Saikasaki, Kitan Channel, Osaka Bay ( Harada 1962), Minabe, Wakayama Prefecture ( Harada 1962), Seto Inland Sea near Hikari, Yamaguchi Prefecture (Sakaji & Tokay 1992; larvae), Siraisi-sima, Seto Inland Sea ( Harada 1962). Shikoku: Muroto Peninsula, Kochi Prefecture ( Matsuzawa 1977).

Taiwan: Northern Taiwan ( Chan & Yu 1993; Huang 1994; Wang et al. 1998), Keelung City ( Chan & Yu 1986).

The examined material extends the known range of the species to New Caledonia and the Fiji Islands.

HABITAT. — In New Caledonia the species has been found at depths between (230-)246 and 658(-680) m. Depth records of the Korean, Japanese and Taiwanese material are very scarce and vague. Kim & Park (1972) give the depth as probably 30 m, Chan & Yu (1993) give the depth at which the species occurs as “probably less than 50 m ”. Also the bottom on which the species lives is seldom mentioned “in rocky areas” ( Motoh 1972); collected by “diving around coral reef” ( Chan & Yu 1986).

DESCRIPTION

The rostrum is truncated with the anterior margin slightly emarginate and the base constricted. It bears a strong and sharply pointed rostral tooth, which reaches beyond the end of the anterior margin of the rostrum. There is no pregastric tooth, but the gastric tooth is well-developed; although it is large, it is lower and much less pronounced than in G. timidus n. comb. and its anterior height is distinctly less than half the distance between the anterior end of the gastric tooth and the tip of the rostral tooth. This is the easiest character to distinguish adults of the two species. Behind the rostral tooth there are about four transverse rows of low and flat squamae, behind the gastric tooth there are about eight such rows of one to five squamae. The upper margin of the gastric tooth is about straight and reaches the cervical groove. The cardiac tooth is rather low and placed immediately behind the cervical groove and is distinctly smaller than the rostral tooth, it ends in a double tip, the two points of which may be acute or more blunt, rarely there is a single tip. It is followed by about seven transverse rows of two to five squamae, which often are more or less fused.

The branchial carina is widely interrupted by the cervical groove, the gap shows no tubercle. The anterior branchial carina ends in two sharp teeth of equal size, that are placed on the inner orbital margin. Behind the posterior of these two teeth there are two diverging carinae which are not very distinct and carry small squames. The posterior branchial carina ends anteriorly in a welldeveloped sharply pointed tooth, which overhangs the cervical groove. Behind this tooth the carina shows a row of some eight squamiform tubercles. Outside this row, there are more simi- lar tubercles. At the place of the anterior submedian carina there are some tubercles, two of which are much larger and flatter than the others. At each side of the posterior postrostral carina there is a group of several flattened tubercles that reach almost to the intermediate row. The intermediate row consists of about seven rather small rounded tubercles; between its anterior end and the cervical gap of the branchial carina two or three parallel more or less elongate tubercles are placed in a short oblique row. Two more flattened tubercles are found near the inner margin of the posterior branchial carina.

The orbital margin is formed by a smooth carina, which at its outer end bears a sharp small spine. Behind the orbit there is an indistinct postorbital tubercle.

The lateral margin of the carapace ends in a strong anterolateral tooth followed by a few flattened squamiform tubercles. The mediolateral area of the lateral margin also ends in a sharp tooth, followed by about four squamiform tubercles that merge with the tubercles of the intercervical area. The posterolateral margin ends in a sharp anterior tooth followed by about seven broad squamiform tubercles. Some broad tubercles are also present in the posterior part of the space between the posterior branchial and posterolateral carinae.

The marginal groove along the posterior margin of the carapace is distinct, but neither very deep nor very wide. Between it and the posterior margin of the carapace a parallel transverse groove is present; between the two grooves flattened tubercles are visible. Before the marginal groove there are two rows of rather indistinct tubercles. The median incision of the posterior margin of the carapace is small but distinct.

The first abdominal somite has a complete, uninterrupted and distinct transverse groove over the middle; about 20 short longitudinal grooves extend from the transverse groove posteriorly. The posterior margin of somites I to IV has a median incision, which is distinct in the anterior somites, less so in the fourth. In the fifth and sixth somites the posterior margin is somewhat convex in the middle and not incised. The smooth anterior part of the somites has the surface perfectly smooth and naked, at most with some inconspicuous dimples or an interrupted groove.

The abdominal somites show no median carina. There is the normal arborescent sculpturation of deep and narrow grooves in the posterior half of each somite. In the middle of the dorsal surface the grooves form a lobulated figure that is slightly longer than wide.

The pleura of somite I are small and bilobed, those of somites II to IV end in a sharp posteroventrally directed tooth. The tip of the pleura of somite V is blunt and directed down. The margins of the pleura are smooth, at the most a faint crenulated pattern is formed on the anterior margin by the arborescent markings of pleura II to IV. The four teeth at the end of the hard part of the telson are of about the same length, the outer teeth may be slightly narrower than the inner; there is no denticulation between the teeth.

The anterior margin of the antennular somite is incised in the middle and bears two blunt teeth in the lateral part.

The distal margin of the last (sixth) segment of the antenna is slightly convex and bears five distal teeth, the outer of which is broader and shorter than the others, which narrow gradually distally into a sharply pointed top. A sixth tooth is placed on the inner margin of the segment, which sometimes shows an indistinct incision somewhat below this tooth. The fifth segment bears the usual pair of sharp teeth on the upper distal margin. The anterior margin of the fourth segment bears two large and sharply pointed teeth, placed close together near the articulation with the fifth segment, sometimes only one tooth is present here. Between these teeth and the apex of the fourth segment, the anterior margin is entire. The outer margin of the segment bears two welldeveloped sharply pointed teeth (the tip of the segment not included). The inner margin of the fourth segment, near the articulation with the fifth, bears a sharply pointed tooth. The upper surface of the fourth segment is smooth with a single sharp carina extending from the base to the tip of the segment. The third segment has two teeth on the mediad side of the anterior margin; the outer of these is longer and slightly stronger than the inner.

The anterior margin of the epistome is slightly convex and incised in the middle. The anterolateral tooth is blunt and slightly less than rectangular. P.1 is distinctly more robust than the other legs. Its dactylus is about as long as that of P.2 and longer than those of P.3 to P.5. No hairy fringes are found on any of the dactyli. The propodus of P.1 is about 1.6 times longer than high, being highest basally and tapering distally; it is smooth and without hair. The carpus is short, cupshaped and smooth. The merus is about as long as propodus and carpus combined; it is 1.5 times as long as high and shows a longitudinal hairy groove in the lower part of the outer surface. The propodus of P.2 is slender and almost cylindrical, being slightly higher at the base than distally, it is about twice as long as the dactylus and about four times as long as high; it shows no hairy grooves and no dorsal hairy fringe. The merus of P.2 is longer than propodus and carpus together, it is about cylindrical and shows a hairy groove in the upper part of the outer surface. The dactylus of P.3 is slightly shorter than that of P.2. The propodus of P.3 is flattened and distinctly higher than the merus, it is also much higher than the propodus of P.2 or P.4: it is about 2.5 times as long as high. It has a dorsal fringe of short hairs along the entire dorsal margin and two distinct and wide longitudinal hairy grooves on the outer surface.The lower margin of the propodus is straight with a rounded anterior angle; there is no tooth here. The carpus of P.3 is short and has a fringe of short hairs in the distal part of the dorsal margin and a hairy groove on the outer surface. The merus is longer than carpus and propodus combined, it is much narrower than the propodus, being more than six times as long as high. It has a longitudinal hairy groove in the upper part of the outer surface and one on the lower surface. P.4 is about as long as P.3, but P.5 is much short- er. None of the segments of P.4 and P.5 have a dorsal fringe of hairs; the propodus, carpus and merus show a longitudinal hairy furrow on the outer surface, but this is often indistinct or interrupted; the merus also has a ventral hairy groove. The anterior margin of the thoracic sternum is produced forward; each half of the margin is either straight or somewhat concave. A small but distinct median triangular incision separates the two halves, it continues posteriorly as a groove; a triangular area around the groove is sunken. The thoracic sternites show a rounded transverse ridge extending over the full width of the anterior part. No median tubercles are present, at most there is an indistinct median elevation on the last ridge. In the males the posterolateral angle of the sternum shows a short rather sharp tooth at the base of P.5; the smallest female shows there a small but rather sharp tooth, followed by a lower rounded lobe; the situation being similar to that of males and small females of G. timidus n. comb. In all other females at most two very low and weak lobes are visible there.

In the males the pleopods of abdominal somite II are small, have the endo- and exopod similar, both are short and narrow, with the exopod only slightly wider and shorter than the endopod. The pleopods of somites III to V have the exopod rather wide and leaf-shaped, being more than twice as wide as the exopod of the pleopod of somite II; the endopods of the pleopods of somites III to V are similar to those of somite II, but become smaller in the posterior somites.

Size

In the examined males cl. is 11 to 30 mm; the non-ovigerous females have cl. 10 to 36 mm, the cl. of ovigerous females is 23 to 31 mm.

Colour

The only trace of colour in the preserved specimens is the presence of a reddish ring in or somewhat below the middle of propodus, carpus and merus of P.1 to P.5. The coloured figure published by Chan & Yu (1993: 209) shows a dark brown animal, with a lighter transverse band over the antennae, and one over the anterior half of the carapace. Light median spots are present on abdominal somites II to V, the one on somite II being by far the broadest. The sixth somite and the tailfan are bright yellowish white. The first abdominal somite shows a large circular dark spot in the middle surrounded by a light ring. A very small bright blue spot is present at the base of the antennulae. The legs have the usual yellowish colour with a dark ring in the basal half of dactylus, propodus and merus. A similar colour pattern, but less distinct, is shown by the colour photograph of this species published by Kim (1977: pl. 36 fig. 75). Motoh (1999), Debelius (1999a, b, 2000), and Minemizu et al. (2000) also published a coloured figure of the species. According to T. Y. Chan (pers. comm.) the presence of the two small bright blue spots at the base of the antennulae is quite characteristic for the species.

Larval development

The late stage phyllosoma of this species was described from Japan by Higa & Saisho (1993) who also provided figures.

REMARKS

The species is close to Galearctus aurora n. comb., but differs in having: 1) the propodus of P.3 much more strongly widened and with hairy grooves; 2) two strong teeth on the anterior margin of the fourth antennal segment; and 3) no sharply pointed posteriorly directed teeth on the fifth thoracic sternites of the female. It can immediately be distinguished from G. timidus n. comb. by the low gastric tooth.

Galearctus aurora ( Holthuis, 1982) n. comb.

( Fig. 68A, B )

Scyllarus aurora Holthuis, 1982: 847 , figs 1, 2; 1993: 184, fig. 3. — Manac’h & Carsin 1985: 473. — Sekiguchi 1986a: 1289-1291; 1986b: 15; 1987a: 331; 1987b: 417, 418; 1988: 3; 1992: 212. — Phillips & McWilliam 1989: 353, 354, 357. — Sekiguchi et al. 1989: 81, text-fig. 1, pl. 1. — Poupin 1996a: 16, pl. 7 col. fig. a.; 1996b: 11, 96. — Fransen et al. 1998: 65.

Scyllarus timidus – Tinker 1965: 42, pl. 9. — M. W. Johnson 1971a: 83, figs 22-33. — A. Michel 1971: 472. — Clarke 1972: 313-315 [non Scyllarus timidus Holthuis, 1960 ].

? Scyllarus sp. III – A. Michel 1971: 467, 472, fig. 6F.

TYPE MATERIAL. — Holotype: ov. ( RMNH); paratypes: 5, 3 ( RMNH); 1 (MNHN-Pa 566). Complete informations about paratypes in Holthuis (1982).

TYPE LOCALITY. — Hawaii, Oahu, Barber’s Point, 21°18’N, 158°07’W, 117- 128 m.

MATERIAL EXAMINED. — Taiwan. North coast. Peace Id, Keelung, about 100 m deep, bottom gill-net, 1.VI.2000, T. Y. Chan leg., 1, 4 ov. ( RMNH D 49569).

Philippines. North of Lubang Id, MUSORSTOM 1, stn 57, 13°53.1’N, 120°13.2’E- 13°52.7’N, 120°13.5’E, 96-107 m, 26.III.1976, 1 15 mm, 1 juv. 6 mm (MNHN-Pa 1263).

New Caledonia. Yandé Id , North New Caledonia, about 20°3’S, 163°50’E ; outside the reef, 200 m, 1.IX.1978, 1 badly damaged (MNHN-Pa 1240).

Île des Pins, LAGON, stn 586, 22°48’S, 167°35’E, 57 m, 18.VII.1985, 1 11 mm, 1 ov. 14 mm (MNHN-Pa 1256).

Fiji Islands. SE of Viti Levu , MUSORSTOM 10, stn CP 1349, 17°31.1’S, 178°38.8’E, 244-252 m, 11.VIII.1998, 1 24 mm (photographed; MNHN- Pa 1890) .

DISTRIBUTION. — The species has a rather wide range in the Pacific. In the original description it was report- ed from Hawaii, Japan, Society Islands and New Caledonia (more precise localities are given there). Since then it was reported from the following additional localities. Off Kii-Nagashima, Kii Peninsula, Japan ( Sekiguchi et al. 1989), and from the South Pacific: Tubuai (= Austral) Archipelago (Maria, Rurutu and Tubuai islands), Society Archipelago (Maupiti, Moorea, Raiatea and Tupai islands), Tuamotu Archipelago (Akiaki, Fangataufa, Hao, Makemo, Marutea South, Maria, Mururoa, Tuanake, Tureia and Vanavana islands), Marquesas Archipelago (Fatuhiva and Tahuata islands), Gambier Archipelago; all these South Pacific islands were listed by Poupin (1996b) while in his previous publication ( Poupin 1996a) only the names of the archipelagoes were mentioned. Manac’h & Carson (1985) reported the capture of the species at Mururoa and/or Fangataufa islands, Tuamotu Archipelago.

HABITAT. — The species has been reported from depths between 90 and 300 m ( Poupin 1996a, b). Holthuis (1982: 852) listed the depth records known at that time (117-200 m) and one report from “a depth below 100 feet (= 30 m)”. The present specimens are from depths that do not change the picture (96-107 to 244-252 m), except for the material from Île des Pins, which was taken at 57 m.

DESCRIPTION

The material agrees well with the published description ( Holthuis 1982). In the ovigerous female there is no sharp posterolateral spine on the sternum; the spine is very distinct and sharp in the male. G. aurora n. comb. and G. rapanus n. comb. are the species in which the propodus of the third leg is atypical for the genus Galearctus n. gen. This propodus, namely, is rather slender, only slightly wider and flatter than the propodus of P.2 and without hairy grooves. The anterior margin of the thoracic sternum which is produced in the middle, shows that the species belongs to the present genus.

Size

In the literature the cl. is given as 15-39 mm. The males (cl. to 31 mm) seem to be somewhat smaller than the females (cl. to 38 mm). The present specimens from Île des Pins are remarkably small, the cl. of the ovigerous female being only 14 mm.

Colour

The Fiji specimen was photographed in colour when just caught. It shows the body variegated with brown and whitish spots and areas. The tips of many spines are white. A mostly whitish transverse band extends behind the anterior margin of the carapace and a similar band is seen some distance before the posterior margin. A broad whitish spot extends in each half of the carapace from the middle of the cervical groove posteriorly; a short transverse brownish band covers the cardiac tooth. The abdominal somites are mottled with brown and whitish, except the tailfan which is entirely whitish. The most conspicuous part of the colour pattern is formed by a large reddish brown median spot on the first abdominal somite which is flanked at either side by about six alternating brown and white lines, which extend backward over the larger part of the second somite. Poupin (1996a: pl. 7 fig. a) published a coloured figure of the species.

Larvae

The stage V, VII and IX phyllosoma’s from the Hawaiian Islands that M. W. Johnson (1971a) brought to Scyllarus timidus more likely belong to the present species. Likewise the phyllosomas from New Caledonia and the New Hebrides, that Michel named Scyllarus sp. III, and that he identified with Johnson’s just mentioned phyllosomas, probably belong here as well. Poupin (1996b: 11) identified Michel’s (1971) Scyllarus sp. IV and V with the present species, but Michel (1971: 472) clearly indicated only sp. III as identical with M. W. Johnson’s S. timidus larvae, while he assigned his Scyllarus sp. V to S. modestus (= Eduarctus modestus n. comb.) and gave no opinion on sp. IV. Phillips & McWilliam (1989) described and figured a scyllarid nisto stage, which they thought to most likely belong to the present species.

Figures

FIG. 25. — Galearctus kitanoviriosus (Harada, 1962) n. comb., New Caledonia, VOLSMAR, stn DW 39, (MNHN-Pa 1384); A, abdominal somites I and II in lateral view; B, thoracic sternum; C-G, pereiopods 1 to 5. Scale bar: 4 mm.

FIG. 68. — A, B, Galearctus aurora (Holthuis, 1982) n. comb.; A, Fiji Islands, SE of Viti Levu, MUSORSTOM 10, stn CP 1349, carapace length 24 mm (MNHN-Pa 1890), photo B. Richer de Forges; B, off Haputo, Guam, 125 m, 8.X.1997, photo G. Paulay, det. T. Y. Chan; C, Chelarctus crosnieri n. gen., n. sp., Tonga Islands, SW of Tongatapu, BORDAU 1, stn CP 1541, holotype carapace length 72 mm (MNHN-Pa 1887), photo J.-S. Philippe; D-F, Eduarctus martensii (Pfeffer, 1881) n. comb., New Caledonia, Lagon Nord- Ouest, photos P. Laboute; D, LAGON, stn DW 919, bopyrized carapace length 8 mm (MNHN-Pa 1306); E, LAGON, stn DW 933,; F, LAGON, stn DW 1024, carapace length 10 mm (MNHN-Pa 1321).