Australocarcinus kanaka 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 : 146-154

Australocarcinus kanaka Davie & Guinot, 1996

( Figs. 93 C; 94B, H; 95C, D; 96C, D; 98C, D; 99C, D)

Australocarcinus kanaka Davie & Guinot, 1996: 279 , figs. 1‒4, 6, 8 [type locality: New Caledonia] .—Ng et al. 2008: 76 [in list], 77, fig. 60 [colour] [New Caledonia].— Anger et al. 2015: 329.

Type material. Holotype male (11.1 × 9.5 mm) (MNHN-IU-2014-12818, ex MNHN-B25279), New Caledonia, Col d'Amoss , near Ouégoa, in freshwater stream, l00 m altitude, R. Raven coll., 13.11.1993.

Paratypes: 2 females (9.2 × 11.2 mm, 10.4 × 12.4 mm) (MNHN-IU-2014-12819, ex MNHN-B25280), rivière Pangou, P. Bouchet coll., 300 m altitude, 13.07.1993 —1 male (7.3 × 8.7 mm) (MNHN-IU-2014-12820, ex MNHN-B25281), rivière Oualème, Ouène, P. Bouchet coll., 14.07.1993.—1 male, 2 females, 1 juvenile (MNHN- IU-2014-12821, ex MNHN-B25282), Koumac, Three Creeks, 1993). Other paratypes (5 males, 3 females) (see Davie and Guinot, 1996).

Other material examined. New Caledonia. 2 females (7.4 × 8.5 mm, 8.5 × 9.8 mm) ( ZRC 2009.111 ), Koumac, northern New Caledonia, P.K.L. Ng coll., 11.2006.

Diagnosis. Carapace ( Fig. 93 C; Davie & Guinot 1996: figs. 1, 3A) subquadrate, 11.2 wider than long; front bilobed, with slight median cleft; dorsal surface smooth. Anterolateral margins arcuate, with 3 wide, short, dorsoventrally flattened teeth. Orbits short. Eye peduncle short ( Fig. 94 B; Davie & Guinot 1996: fig. 3A), does not fill orbit, mobile, cornea enlarged, pigmented. Epistome ( Fig. 94 B) compressed, posterior margin with median lobe with fissure, circular lateral margins without fissures. Third maxillipeds ( Fig. 94 H; Davie & Guinot 1996: fig. 3C) leaving gap when closed; merus quadrate, auricular anteroexternal angle, ischium quadrate, slightly longer than merus. Chelipeds ( Figs. 93 C; 95C, D; Davie & Guinot 1996: figs. 1; 3F) subequal in length, nearly similar in both sexes; cutting margins of both chelae with broad, shallow teeth larger in major chela. Inner margin of cheliped carpus with short, triangular tooth. Ventral surface of cheliped merus bordered by large tubercles. Proportionally short ambulatory legs ( Fig. 93 C; Davie & Guinot 1996: fig. 1), P5 merus not reaching front when folded. Meri smooth. Fused thoracic sternites 1, 2 semicircular, proportionally wide, short. Male pleon ( Fig. 96 C; Davie & Guinot 1996: fig. 3D, E) with lateral margins of somite 6, fused somites 3–5 slightly convex; postero-lateral regions slightly swollen; telson proportionally long; “supplementary plate” ( Fig. 96 D; Davie & Guinot 1996: fig. 3G) conspicuously narrow, short, rectangular. G1 ( Fig. 98 C; Davie & Guinot 1996: fig. 4A) stout, distal part with tapering tip, with short spinules. G2 ( Fig. 98 D; Davie & Guinot 1996: fig. 4B) longer than G1, basal segment curved; distal segment slightly longer than basal segment, apex with lateral pointed tip. Somites of female pleon ( Fig. 99 C) with slightly convex lateral margins; telson proportionally long. Sterno-pleonal cavity of female ( Fig. 99 D) moderately deep, with conspicuously large vulvae widely separated, covering most of thoracic sternite 5 with anterior portion extending into deflected suture 5/6, round, thin lip on outer margin, soft membrane across, leaving proportionally small opening.

Remarks. The posterior margin of the epistome of the holotype male (MNHN-IU-2014-12818, ex MNHN- B25279) consists of a straight median lobe with no median fissure and straight lateral margins. The epistome, however, has a semicircular median lobe with a median fissure in a female (MNHN-IU-2014-12819, ex MNHN- B25280). It is short, with straight lateral margins and without a lower margin in both specimens.

Distribution. Known only from New Caledonia; 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 96. Male anterior thoracic sternum and pleon of species of Australocarcinus. A, B, A. riparius, Australia: male 8.8 × 10.2 mm (ZRC 2006.167); C, D, A. kanaka, New Caledonia: paratype male 5.5 × 6.4 mm (after Davie & Guinot 1996: fig. 3 D, G).

FIGURE 98. Gonopods of species of Australocarcinus and Trogloplax. A, B, Australocarcinus riparius, Australia: holotype male (after Davie 1988: fig. 1 A, B); C, D, Australocarcinus kanaka, New Caledonia: holotype male 9.5 × 11.1 mm (after Davie & Guinot 1996: fig. 4); E, F, Trogloplax joliveti, New Britain: paratype male 20.0 × 27.0 mm (MNHN-IU- 2014 - 10458) (after Guinot 1986: pl. 2 F, G); G ‒ J, Trogloplax joliveti, New Britain: male 15.7 × 18.6 mm (ZRC 2015.294). Scales: G, J = 1.0 mm; H, I = 0.5 mm.

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.