Australocarcinus palauensis Davie & Guinot, 1996

Ng, Peter K. L. & Castro, Peter, 2016, Revision of the family Chasmocarcinidae Serène, 1964 (Crustacea, Brachyura, Goneplacoidea), Zootaxa 4209 (1), pp. 1-182 : 158-159

Australocarcinus palauensis Davie & Guinot, 1996

( Figs. 93 D; 94C, D, I; 99E, F)

Australocarcinus palauensis Davie & Guinot, 1996: 282 , figs. 5, 8 [map] [Belau = Palau].—Ng et al. 2008: 76 [in list].

Type material. Holotype female (5.8 × 7.1 mm) ( USNM 277853 ), Belau [= Palau], Addeids River , Babelthuab I., in small fast tributary, coll. D. Frey, 5.03.1946.

Diagnosis (modified from Davie & Guinot 1996). Carapace ( Fig. 93 D; Davie & Guinot 1996: fig. 5A) subrectangular, 1.2 wider than long; front bilobed, with slight median cleft; dorsal surface smooth. Anterolateral margins arcuate, cristate, without teeth. Orbits short. Eye peduncle short, does not fill orbit, cornea enlarged. Third maxilliped ( Fig. 94 D, I) merus quadrate, ischium quadrate, slightly longer than merus. Chelipeds subequal in length; cutting margins of both chelipeds with broad, shallow teeth larger in major chela ( Fig. 95 E, F).

Proportionally short ambulatory legs ( Fig. 93 D). Meri smooth. Somites of female pleon with slightly convex lateral margins; telson proportionally long ( Fig. 99 E). Sterno-pleonal cavity of female shallow, vulvae not fully developed ( Fig. 99 F). Male unknown.

Remarks. The species is known from a single young female specimen (pleon, pleopods and vulvae not mature, Fig. 99 F) so the morphology of males, including the pleon, posterior part of thoracic sternum, G1, and G2, remains unknown.

Distribution. Known only from Belau [= Palau] (western Pacific Ocean); rivers.

Figures

FIGURE 93. Overall dorsal view of species of Australocarcinus and Trogloplax. A, Australocarcinus riparius, Australia: male 8.8 × 10.2 mm (ZRC 2006.167); B, A. riparius, Australia: female 9.0 × 11.3 mm (ZRC 2006.167); C, Australocarcinus kanaka, New Caledonia: female 8.5 × 9.8 mm (ZRC 2009.111); D, Australocarcinus palauensis, Palau: holotype female (5.8 × 7.1 mm) (USNM 277853); E, F, Trogloplax joliveti, New Britain: holotype male 16.0 × 21.0 mm (MNHN-IU- 2014 - 10457) (after Guinot 1986: pl. 1 A, B); G, Trogloplax joliveti, New Britain: male 15.7 × 18.6 mm (ZRC 2015.294); H, Trogloplax joliveti, New Britain: female 14.1 × 16.8 mm (ZRC 2015.295).

FIGURE 94. Frontal view and third maxilliped of species of Australocarcinus and Trogloplax. A, Australocarcinus riparius, Australia: male 8.8 × 10.2 mm (ZRC 2006.167); B, Australocarcinus kanaka, New Caledonia: female 8.5 × 9.8 mm (ZRC 2009.111); C, D, Australocarcinus palauensis, Palau: holotype female (5.8 × 7.1 mm) (USNM 277853); E, Trogloplax joliveti, New Britain: male 15.7 × 18.6 mm (MNHN-B 20136); F, Trogloplax joliveti, New Britain: female 14.1 × 16.8 mm (ZRC 2015.295); G, Australocarcinus riparius, Australia: holotype male (after Davie 1988: fig. 1 C); H, Australocarcinus kanaka, New Caledonia: paratype female 9.5 × 11.1 mm (after Davie & Guinot 1996: fig. 3 C); I, Australocarcinus palauensis, Palau: holotype female (5.8 × 7.1 mm) (USNM 277853) (after Davie & Guinot 1996: fig. 5 B); J, Trogloplax joliveti, New Britain: holotype male 16.0 × 21.0 mm (MNHN-IU- 2014 - 10457) (after Guinot 1986: pl. 2 B).

FIGURE 95. Chelae of species of Australocarcinus and Trogloplax. A, B, Australocarcinus riparius, Australia: male 8.8 × 10.2 mm (ZRC 2006.167); C, D, Australocarcinus kanaka, New Caledonia: female 8.5 × 9.8 mm (ZRC 2009.111); E, F, Australocarcinus palauensis, Palau: holotype female (5.8 × 7.1 mm) (USNM 277853); G, H, Trogloplax joliveti, New Britain: male 15.7 × 18.6 mm (ZRC 2015.294).

FIGURE 99. Female pleon and vulvae of species of Australocarcinus and Trogloplax. A, B, Australocarcinus riparius, Australia: female 9.0 × 11.3 mm (ZRC 2006.167); C, D, Australocarcinus kanaka, New Caledonia: female 8.5 × 9.8 mm (ZRC 2009.111); E, F, Australocarcinus palauensis, Palau: holotype female (5.8 × 7.1 mm) (USNM 277853); G, H, Trogloplax joliveti, New Britain: female 14.1 × 16.8 mm (ZRC 2015.295). A, C, E, G, thoracic sternum with pleon; B, D, F, H, female sterno-pleonal cavity with vulvae.