Eucrate solaris Yang & Sun, 1979

CASTRO, PETER & NG, PETER K. L., 2010, Revision of the family Euryplacidae Stimpson, 1871 (Crustacea: Decapoda: Brachyura: Goneplacoidea), Zootaxa 2375 (1), pp. 1-130 : 37-40

Eucrate solaris Yang & Sun, 1979

( Figs. 7C–F ; 11A–F ; 15G–I)

Eucrate solaris Yang & Sun, 1979: 1 , 8, fig. 1, plate, figs. 1, 2, 7 [ China]. — Dai et al. 1986: 372 [in key], 373, fig. 196(1), pl. 54, fig. 3 [ China] — Chen 1998: 277, 310 [in list], fig. 8. — Dai & Yang 1991: 401 [in key], 402, fig. 196(1), pl. 54, fig. 3 [ China]. — Naiyanetr 1998: 78; 2007: 90 [Gulf of Thailand]. — Ng et al. 2001: 34, fig. 7h [ Taiwan]. — Hsueh & Huang, 2002: 130 [in key], 133, figs. 8H, 17. — Ng et al. 2008: 78 [in list]. — Yang et al. 2008: 770 [in list] [ China].

Eucrate crenata — Shen & Jeng 2005: 153, colour photograph [ Taiwan]. [not Eucrate crenata (De Haan, 1835) ]

Type material. Male holotype ( BMNH J79136 ) ; female allotype, 21.3 mm × 27.0 mm ( BMNH J79137 ; Fig. 11A ), 1 male, 3 female paratypes ( BMNH) .

Type locality. China, Guanxi Province , Beihai .

Material examined. (?) Japan. Ryukyu Islands . Kamejima I., Ahra, coral reef, intertidal, 13.06.1995, K. Nomura coll.: 1 female ( CBMZC 3191 ) .

Taiwan. Kaohsiung County, Tung-Kang fishing port, P. K. L. Ng coll., 05.05.1996: 1 female ( ZRC 1997.752 ) .

I-Lan County, Tahsi, K. X. Lee coll., 2000: 1 female, 21.4 mm × 26.2 mm ( ZRC 2001.0023 ) .

Penghu Bay , 50 m, 3.31.1998: 1 female (ASIZ-71966); Y. L. Shen coll., 5.10.2006: 1 male, 23.6 mm × 28.1 mm (ASIZ-74626) .

Philippines. Bohol. Balicasag I., off Panglao I., tangle nets, purchased from fishermen, 200–300 m, 12.2000 : 4 males, 20.0 mm × 25.0 mm, 21.6 mm × 26.4 mm, 23.4 mm × 28.5 mm, 23.5 mm × 28.4 mm ( ZRC 2001.0394 ) ; 50–500 m, 28.11.2001: 1 male, 19.5 mm × 23.5 mm ( ZRC 2001.0537 ) , 1 female ( ZRC 2001.0538 ) , 1 male, 2 females ( ZRC 2001.0655 ) ; 200–300 m, 06.2002: 1 male, 1 female ( ZRC 2002.0650 ) ; 25–30.07.03: 6 males, 11 females ( ZRC 2004.0751 ) ; 50–500 m, 02.03.2004: 1 male, 3 females ( ZRC 2004.0733 ) ; 25– 30.07.2003: 5 males, 7 females ( ZRC) ; 04.2004, 1 male ( ZRC 2004.0762 ) , 04.2004: 1 male, 15.5 mm × 18.6 mm, 2 females, 20.3 mm × 24.2 mm, 22.7 mm × 27.6 mm ( MNHN-B29727 ) ; 29.05.2004: 2 males, 4 females ( ZRC 2009.0976 ) ; 05.2004: 1 female ( ZRC 2009.0977 ) .

PANGLAO 2004: stn. P1, 09°36.00’N, 123°45.00’E, 150–200 m, 27.06.2004: 1 female ( ZRC 2009.0978 ) , 1 male ( ZRC 2009.0979 ) . – Stn. P4, 11.06.2004: 1 male ( ZRC 2009.0980 ) . – Stn. L 40, Panglao I., Tangnan, 9°37.3'N, 123°46.5'E, 100–120 m, 24.06.2004: 1 male, photograph, 23.3 mm × 28.1 mm ( ZRC 2008.1333 ) .

Vanuatu. SANTO 2006: stn. EP04, northeast Aoré I., Aimbué Bay , 15°33.0/33.4’S, 167°11.7/12.8’E, tangle net, 89–109 m, 12.09.2006: 2 males, 26.2 mm × 31.6 mm, 25.6 mm × 31.1 mm, 1 female, 22.0 mm × 27.3 mm ( ZRC 2008.1237 ) . – Stn. EN 31, east Aoré I., Aimbué Bay, 15°32.9’S, 167°12.9’E, traps, 107 m, 12.09.2006: 10 males, 17.3 mm × 20.3 mm – 29.4 mm × 35.0 mm, 4 females, 19.5 mm × 23.8 mm – 25.0 mm × 31.5 mm ( ZRC 2008.1238 ) . – Stn. EP 10, east Aoré I., 15°34.5/38.0’S, 167°05.1/13.6’E, tangle net, 45–101 m, 15.09.2006: 1 male, 17.6 mm × 22.3 mm ( MNHN-B31628 ) . – Stn. EP 12, Scorff Passage, 15°31.9’S, 167°15.1’E, tangle net, 97 m, 16.09.2006: 1 female, photograph, 22.2 mm × 27.7 mm ( MNHN-B31629 ) . – Stn. EP 18, Aoré I., Aimbué Bay , 15°33.1/33.3’S, 167°11.8/12.2’E, tangle net, 71–102 m, 18.09.2006: 4 males, 18.9 mm × 22.6 mm – 26.2 mm × 32.1 mm, 2 females, 18.4 mm × 22.5 mm, 24.5 mm × 30.2 mm ( MNHN-B31630 ) . – Stn. EP15, northeast Urélapa I., 15°36.6/36.7’S, 167°01.7/02.1’E, tangle net, 103–108 m, 16.09.2006: 1 female, 20.8 mm × 25.9 mm ( MNHN-B31631 ) , 3 males, 1 female ( MNHN-B31988 ) . – Stn. EP21, northwest coast of Mao I., 15°37.7’S, 167°5.2’E, tangle nets, 99 m: 1 male, 21.0 mm × 25.4 mm, 1 female, 20.8 mm × 25.0 mm ( MNHN-B31989 ) . – Stn. EP 23, 15°32.8/33.0’S, 167°12.1/12.3’E, north Aoré I., Aimbué Bay, tangle net, 74–88 m, 22.09.2006: 1 male, 25.6 mm × 30.7 mm, 1 female, 24.4 mm × 29.6 mm ( MNHN-B31632 ) . – Stn. EP 24, west Urélapa I., 15°36.5’S, 167°00.9/01.7’E, tangle net, 108–121 m, 25.09.2006: 1 pre-adult female, 15.2 mm × 18.5 mm ( ZRC 2008.1334 ) . – Stn. AT 41, 15°36.7/37.0’S, 167°02.7/02.8’E, east Urélapa I., 88–118 m, 28.09.2006: 1 female, 24.7 mm × 30.8 mm ( ZRC 2009.0075 ) . – Stn. FP 48, Aoré I., Aimbué Bay , 15°32.4’S, 167°12.7’E, tangle net, 45–50 m, 03.10.2006: 1 male, 21.5 mm × 26.5 mm, 1 female 22.0 mm × 27.2 mm, 1 ovigerous female, 24.8 mm × 31.1 mm ( MNHN-B31633 ) . – Stn.FP 49, Aoré I., Aimbué Bay , 15°32.4’S, 167°12.7’E, tangle net, 45–50 m, 03.10.2006: 3 males, 19.8 mm × 25.1 mm – 25.7 mm × 31.1 mm, 1 pre-adult female, 8.3 mm × 10.4 mm, 1 female, 22.8 mm × 27.7 mm ( MNHN-B31634 ) . – Stn. EP27, Tutuba I., 15°33’S, 167°16.0’E, tangle net, 155 m, 07.10.2006: 1 female, 24.5 mm × 30.1 mm ( ZRC 2008.1239 ) . – Stn. EN 33, east Aoré I., Aimbué Bay, 15°32.6’S, 167°12.5’E, traps, 80 m, 14.10.2006: 4 females, 22.6 mm × 27.9 mm – 25.0 mm × 31.7 mm ( ZRC 2008.1240 ) . – Stn. EP 35, east Aoré I., off Aimbué Bay , 15°34.9/35.1’S, 167°13.9/14.1’E, tangle net, 10–51 m, 15.10.2006: 2 males, 21.1 mm × 26.2 mm, 25.3 mm × 30.5 mm, 1 female, 22.2 mm × 27.1 mm ( MNHN-B31635 ) . – Stn. EP 40, west Tutuba I., 15°33.1/33.6’S, 167°16.4/16.5’E, tangle net, 125–156 m, 18.10.2006: 1 female, photograph, 26.2 mm × 31.5 mm ( ZRC 2008.1335 ) , 1 female, photograph, 21.9 mm × 26.7 mm ( ZRC 2008.1336 ) .

Diagnosis. Third anterolateral tooth visible (except large individuals), carapace with relatively short posterolateral borders ( Figs. 7C–F ; 11A, B ). P5 propodus slender ( Figs. 7C–F ; 11A, B ). Variegated pattern of irregular red-brown, red-pink dots, spots variously arranged on carapace ( Fig. 7C–F ).

Remarks. Diagnostic of E. solaris is a carapace that is sculptured by ridges and deep, sometimes setous grooves, most especially in the largest specimens. A groove extends from the median notch of the front, cutting through a transverse ridge that extends across the frontal region posterior to the front before bifurcating on the mesogastric region. A depression, sometimes setous, extends posterior to each orbit and continuing to the anterolateral border between the first and second anterolateral teeth. Anther groove, typically setous, extends from each of the third anterolateral teeth into the mesogastric region. These grooves are particularly conspicuous in large specimens collected from deep-water tangle nets in the Philippines (e.g. ZRC 2001.0394, 2001.0655, 2004.0751). The supraorbital borders and the hepatic regions in some of these specimens are sculptured by relatively deep, round or irregular depressions.

The first anterolateral tooth is triangular in outline; the second, the largest, is also triangular but slightly dorsally elevated; the third is the smallest but conspicuous in relation to other species of Eucrate .

Eucrate solaris can be differentiated from all other known species of Eucrate by its distinctive variegated colour pattern. Preserved specimens, which do not show the distinctive colour pattern, do show two diagnostic triangular or hexagonal patterns on the mesogastric region. Also diagnostic is the short tomentum, never conspicuous as in other species of Eucrate , along the anterior margin of the cheliped carpus.

Eucrate solaris is closest to E. crenata in the general shape of its carapace, particularly in the anterolateral teeth: first tooth being well developed, triangular, and with an obtuse tip; second tooth the largest, triangular, dorsally salient, and with an obtuse tip; third tooth short, with an obtuse tip, and always present. Eucrate solaris can be morphologically differentiated by: (1) a row of a varying number of obtuse granules and conspicuous tubercles on the outer (dorsal) margin of the cheliped merus (only short granules in E. crenata ), (2) the absence of a conspicuous tomentum, only fewer and shorter setae, along the anterior margin of the cheliped merus (long and conspicuous tomentum in E. crenata ), and (3) a relatively shallow frontal notch ( Fig. 12A–C ) (well defined in E. crenata ; Fig. 3B–D ). The colour pattern of preserved specimens of both E. solaris and E. crenata invariably consists of two red-brown dots on the branchial region and many small dots on the anterior third of the carapace. In E. solaris , however, two roughly triangular or a single hexagonal pattern remains on the mesogastric region, a pattern that is never present in E. crenata .

In addition to its unique colour pattern, E. solaris can be distinguished from E. alcocki , E. formosensis , and E. sexdentata by having well developed third anterolateral teeth, which, although small, is always visible ( Fig. 11A, B ) whereas in the other three species the teeth are absent or only evident by a slight elevation on each of the relatively long posterolateral borders of the carapace. As in E. alcocki and E. formosensis , however, the frontal notch is very small or absent. The P5 propodus of E. solaris is slender ( Fig. 11A, B ) whereas it is noticeably short and wide in E. tripunctata ( Figs. 12 ; 13C ; Campbell 1969: fig. 4G); the first anterolateral teeth of E. dorsalis are short ( Figs. 5 ; 6A–C ) and in the larger specimens all three anterolateral teeth become even shorter ( Campbell 1969: figs. B, K) in contrast to the more conspicuous teeth of E. solaris .

Colour pattern. Variegated pattern of irregular red-brown and red-pink dots and spots symmetrically but variously arranged on the carapace ( Fig. 7C–F ). Two small, irregular spots are located on the branchial region at the inner end of the v-shaped groove that runs from each third anterolateral tooth; two triangular or hexagonal patterns on the mesogastric region (two dark spots in a Philippines specimen; Fig. 7C ). There is a white band along the proximal portion of the meri of the ambulatory legs, the remaining portion being red-pink. Freshly preserved specimens from the Philippines also showed a red-brown sternum continuing as a vertical band along the margins of the abdomen and extending into the posterior portion of the carapace, which can be seen in the colour photograph ( Fig. 7D ). The fingers can be dark or light brown.

A colour photograph of presumably fresh material from Taiwan ( Shen & Jeng 2005: 153, as E. crenata ) shows a yellow carapace with a red-brown, elongated spot across the mesogastric region of the carapace bordered by two large, red-brown spots. The chelipeds are yellow and the ambulatory legs light yellow, with distal portions with wide, red-brown bands. There are many variations in the number and shape of the carapace spots, however, being round, elongated or crescent-shaped, and two, three or four in number ( Fig. 7C–F ; Yang & Sun 1979: plate, fig. 1).

Distribution. Taiwan, South China Sea ( Yang & Sun 1979), Philippines, Gulf of Thailand, Vanuatu, and questionably the Ryukyu Is., Japan. Depth: subtidal to at least 200 m, but also collected from tangle nets reaching 500 m (see Ng et al. 2009).

Figures

FIGURE 3. Eucrate crenata (De Haan, 1835); A–F, male neotype of Pilumnoplax sulcatifrons Stimpson, 1858 (34.0 mm × 49.1 mm) (QM W27449), Hong Kong, New Territories, Tolo Channel; G, female (22.1 mm × 27.1 mm) (ZRC 2002.0493), China, Qingdao. A, overall view; B, frontal view showing orbits and antennae; C, anterior portion of male thoracic sternum and abdomen; D, third maxillipeds, antennules, antennae and orbits; E, outer surface of right chela; F, posterior portion of male thoracic sternum and abdomen; G, female thoracic sternum and vulvae. Abbreviations: a1–a6 = male abdominal somites 1–6, respectively; cx5 = coxa of fifth pereopod (P5); s3–s7 = thoracic sternites 3 to 7, respectively; t = telson; v = vulva.

FIGURE 5. Eucrate dorsalis (White, 1849); A, male paralectotye (NHM 1850.112) as originally illustrated in White (1849: pl. 6, fig. 2), Australia, Queensland; B, C, dry male paralectotype of Cancer (Galene) dorsalis White, 1849 (36.6 mm × 46.5 mm; NHM 1850.112), Australia, Queensland; D, dry male lectotype of Cancer (Galene) dorsalis White, 1849 (20.2 mm × 24.8 mm; NHM 1852.71), Australia, Queensland; Galene? laevimanus Lucas, in Jacquinot & Lucas 1853; E, F, dry male lectotype (28.7 mm × 36.5 mm) (MNHN-B2960); A, D, E, overall views; B, F, dorsal views of carapaces; C, ventral view of carapace. Photo credits: B–D by P. Crabb (NHM); E, F by J.-F. Dejouannet (IRD, Paris).

FIGURE 6. Eucrate dorsalis (White, 1849); A, female (31.7 mm × 40.7 mm) (QM W12788), Australia, Queensland, Townsville Closure; B–F, male (39.0 mm × 46.7 mm) (QM W3191), Australia, Queensland, Bundaberg. A–B, overall views; C, frontal view showing orbits and antennae; D, outer surface of right chela; E, anterior portion of male thoracic sternum and abdomen; F, posterior portion of male thoracic sternum and abdomen.

FIGURE 7. Fresh colours of Eucrate species. A, Galene? laevimanus Lucas, in Jacquinot & Lucas, 1853 [= E. dorsalis (White, 1849]), male lectotype (28.7 mm × 36.5 mm) (MNHN-B2960) (after Lucas, in Jacquinot & Lucas 1853: pl. 6 fig. 2); B, E. dorsalis (White, 1849), Queensland, Australia; C–F, E. solaris Yang & Sun, 1979; C, male (23.3 mm × 28.1 mm) (ZRC 2008.1333), Philippines, Bohol, Panglao; D, female (26.2 mm × 31.5 mm) (ZRC 2008.1335), Vanuatu, Santo; E, male (19.5 mm × 23.5 mm) (ZRC 2001.0537), Philippines, Bohol, Panglao; F, male (23.6 mm × 28.1 mm) (ASIZ-74626), Penghu Bay, Taiwan. Photo credit: B by Queensland Museum.

FIGURE 11. Eucrate solaris Yang & Sun, 1979; A, female allotype (21.3 mm × 27.0 mm) (BMNJ-J79137), China, Guangxi Province, Beibu Bay; B, C, F, female (21.4 mm × 26.2 mm) (ZRC 2001.0023), Taiwan, I-Lan County, Tahsi; D, E, male (23.3 mm × 28.1 mm) (ZRC 2008.1333), Philippines, Bohol, Panglao. A, B, overall views; C, frontal view showing orbits and antennae; D, anterior portion of male thoracic sternum and abdomen; E, male sterno-abdominal cavity and G1; F, female thoracic sternum and vulvae. Abbreviations: a2, a3 = male abdominal somites 2, 3, respectively; cx5 = coxa of fifth pereopod (P5); G1 = first male pleopod; mg = median groove; p = penis; pb = press-button of the male abdominal-locking mechanism; s4–s8 = thoracic sternites 4 to 8, respectively; sc = sterno-abdominal cavity; t = telson; v = vulva.

FIGURE 12. Fresh colours of Eucrate tripunctata Campbell, 1969. A, female (34.9 mm × 45.5 mm) (ZRC 2003.0606), Thailand, Gulf of Thailand (specimen slightly tilted when photographed); B, male (24.3 mm × 29.4 mm) (ZRC 2003.0606), Thailand, Gulf of Thailand; C, male (37.5 mm × 47.2 mm) (ZRC 2003.0606), Thailand, Gulf of Thailand; D. female (13.6 mm × 16.0 mm) (ZRC 2002.0248), Singapore; E, F, male (7.0 mm × 8.3 mm) (ZRC 2008.066), Singapore.

FIGURE 13. Eucrate tripunctata Campbell, 1969; A, female (29.6 mm × 37.6 mm) (QM W1070), Australia, Queensland, Moreton Bay; B, male (26.7 mm × 33.8 mm) (QM W1070), Australia, Queensland, Moreton Bay; C–F, male (38.0 mm × 48.9 mm) (ZRC 2003.0191), Thailand, Gulf of Thailand. A–C, overall views; D, frontal view showing orbits and antennae; E, anterior portion of male thoracic sternum and abdomen; F, outer surface of right chela.