Scalopidiidae Števčić, 2005

Ng, Peter K. L. & Castro, Peter, 2013, On the genus Scalopidia Stimpson, 1858 (Crustacea: Brachyura: Goneplacoidea: Scalopidiidae), with the description of one new genus and three new species, Zootaxa 3731 (1) : -

Family Scalopidiidae Števčić, 2005

Diagnosis. Carapace subovate ( Figs. 2 , 4 A, C). Epistome longitudinally narrow, partially sunken into branchial cavity; posterior margin as prominent median triangle separated by distinct fissure, tip bilobed ( Figs. 5 ). No endostomial ridges visible. Basal antennal article subrectangular, mobile; subsequent articles, flagellum in orbit ( Figs. 5 ). Basal antennular article large, rectangular, mobile; in large, transverse antennular fossa; second antennal article elongated, longer than width of basal article, unable to fold into fossa ( Figs. 5 ). Eye peduncle relatively stout, completely filling orbit, fused or mobile ( Figs. 5 ). Chelipeds prominently unequal, heteromorphic in adult males ( Figs. 4 B, D, 7). Ambulatory legs proportionally long; dorsal, ventral margins of first, second meri with sharp granules and/or spines; dactylus of P5 recurved ( Figs. 2 , 4 A, C, 8). Male thoracic sternum relatively wide, sternites 1, 2 completely fused forming triangular plate, sternite 3 separated from sternite 2 by concave suture; sternites 3, 4 fused with only lateral sutures discernible, median part depressed; sutures 4–7 medially interrupted, sternite 8 with deep longitudinal groove that does not reach suture 7/8 ( Fig. 9 ). Sterno-abdominal cavity deep, press-button for male abdominal holding present as small rounded tubercle on posterior part of thoracic sternite 5, adjacent to suture 5/6, near edge of sterno-abdominal cavity ( Fig. 1 ). Episternite 7 as a transversely elongated plate, covering penis as it exits coxa of P5, remaining portion of penis exposed along transverse channel or gutter, between thoracic sternites 7, 8 ( Fig. 9 B, D, F, H). Penis coxo-sternal, long, exposed surfaces calcified to form tube ( Fig. 9 B, D, F, H). Male abdomen T-shaped; telson subtriangular with rounded tip ( Figs. 9 , 10 ). G1 sinuous, with open tip, lateral surfaces lined with numerous short spinules ( Figs. 12 A–C, E–G, 13A–C, E, F). G2 short, about a third length of G1, basal segment sinuous with dilated base, distal segment relatively short ( Figs. 12 D, H, 13D, G). Adult female abdomen subovate, not covering entire surface of thoracic sternum; somites 1–6, telson free, separated from each other by deep clefts ( Fig. 11 A, C, E). Female sterno-abdominal cavity relatively shallow ( Fig. 11 B, D, F); vulvae relatively large, positioned on anterior half of somite 6 adjacent to suture 5/6, exposed without operculum or sternal vulvar cover ( Fig. 11 B, D, F).

Figures

FIGURE 1. Posterior thoracic sternum and male abdomen of Scalopidia spinosipes, male (12.2 × 16.7 mm) (ZRC 2000.1604), Singapore. Symbols: a 3 = abdominal somite 3; cx 3 – 5 = coxae 3 – 5, respectively; G 1 — male first gonopod; p = penis; s 5 – 8 = thoracic sternites 5 – 8, respectively.

FIGURE 2. Overall views. Scalopidia spinosipes: A, lectotype male (9.3 × 12.1 mm) (NHM 61.44), Hong Kong; B, paralectotype female (13.3 × 17.7 mm) (NHM 61.44), Hong Kong; C, male (14.8 × 19.2 mm) (ZRC 2006.0073), Hong Kong; D, male (12.2 × 16.7 mm) (ZRC 2000.1604), Singapore; E, male (14.8 × 20.4 mm) (ZRC 2000.1343), South China Sea; F, female (14.2 × 19.2 mm) (ZRC 2000.1343), South China Sea. Scalopidia indica n. sp.: G, holotype male (15.3 × 21.7 mm) (ZRC 1999.0136 a), Andaman Sea; H, paratype female (10.0 × 13.1 mm) (ZRC 1992.10459 - 10461), Penang. Scalopidia spectabilis n. sp.: I, holotype male (11.5 × 16.6 mm) (MNHN-IU- 2013 - 505), Papua New Guinea.

FIGURE 4. Caenopedia ocularia n. sp.: A, B, holotype male (11.2 × 15.0 mm) (MNHN-IU- 2010 - 1573), Madagascar; C, D, paratype female (13.5 × 18.3 mm) (ZRC 2013.1415), Madagascar. A, C, overall dorsal views; B, D, outer views of chelae.

FIGURE 5. Frontal views. A, Scalopidia spinosipes, male (14.8 × 20.4 mm) (ZRC 2000.1343), South China Sea; B, Scalopidia indica n. sp., holotype male (15.3 × 21.7 mm) (ZRC 1999.0136 a), Andaman Sea; C, Scalopidia spectabilis n. sp., holotype male (11.5 × 16.6 mm) (MNHN-IU- 2013 - 505), Papua New Guinea; D, Caenopedia ocularia n. sp., holotype male (11.2 × 15.0 mm) (MNHN-IU- 2010 - 1573), Madagascar.

FIGURE 9. Male thoracic sternum and abdomen. A, B, Scalopidia spinosipes, male (14.8 × 20.4 mm) (ZRC 2000.1343), South China Sea; C, D, Scalopidia indica n. sp., holotype male (15.3 × 21.7 mm) (ZRC 1999.0136 a), Andaman Sea; E, F, Scalopidia spectabilis n. sp., holotype male (11.5 × 16.6 mm) (MNHN-IU- 2013 - 505), Papua New Guinea; G, H, Caenopedia ocularia n. sp.: holotype male (11.2 × 15.0 mm) (MNHN-IU- 2010 - 1573), Madagascar.

FIGURE 10. Male abdominal somite 6. Scalopidia spinosipes: A, male (14.8 × 19.2 mm) (ZRC 2006.0073), Hong Kong; B, male (14.8 × 20.4 mm) (ZRC 2000.1343), South China Sea. Scalopidia indica n. sp.: C, holotype male (15.3 × 21.7 mm) (ZRC 1999.0136 a), Andaman Sea. Scalopidia spectabilis n. sp.: D, holotype male (11.5 × 16.6 mm) (MNHN-IU- 2013 - 505), Papua New Guinea.

FIGURE 11. Female thoracic sternum and vulvae. A, Scalopidia spinosipes, female (14.2 × 19.2 mm) (ZRC 2000.1343), South China Sea; B, Scalopidia indica n. sp., paratype female (10.0 × 13.1 mm) (ZRC 1992.10459 - 10461), Penang; C, Caenopedia ocularia n. sp., paratype female (13.5 × 18.3 mm) (ZRC 2013.1415), Madagascar.

FIGURE 12. Gonopods. A – D, Scalopidia spinosipes, male (14.8 × 20.4 mm) (ZRC 2000.1343), South China Sea; E – H, Scalopidia indica n. sp., holotype male (15.3 × 21.7 mm) (ZRC 1999.0136 a), Andaman Sea. A – C, E – G, left G 1 s; D, H, left G 2 s. Scales: A, D, E, H, 1.0 mm; B, C, F, G = 0.5 mm.