Statommatia knudseni (Serène, 1964) Serene, 1964

Ng, Peter K. L. & Castro, Peter, 2016, Revision of the family Chasmocarcinidae Serène, 1964 (Crustacea, Brachyura, Goneplacoidea), Zootaxa 4209 (1), pp. 1-182 : 76-77

Statommatia knudseni (Serène, 1964) , n. comb.

( Figs. 16 D; 26D; 33C; 45E, F; 54D, E; 61B; 77E‒H)

Hephthopelta knudseni Serène, 1964a: 252 , fig. 18, pl. 22, fig. C [type localilty: New Caledonia]; 1968: 92 [in list].—Ng et al. 2008: 76 [in list].

Type material. Holotype male (4.7 × 6.9 mm) ( ZMUC CRU- 6974 ), New Caledonia, Dana Expedition 1928-30, stn 3612, 21°40’S, 165°24’E., 165–360 m , 27.11.1928.

Other material examined. New Caledonia. DANA EXPEDITION 1928-30 : juvenile female (3.8 × 5.2 mm) ( ZMUC), same data as holotype ; 1 male (3.4 × 4.6 mm) ( ZMUC), same data as holotype .

Diagnosis. Carapace ( Fig. 16 D) subovate, convex dorsally, 1.3‒1.4 wider than long; nearly straight front; anterolateral margins arcuate, conspicuously granular, without distinct lobes or teeth. Eye peduncle ( Fig. 26 D) filling orbit, short, immobile; cornea reduced, with reduced pigmentation. Posterior margin of epistome Posterior margin of epistome ( Fig. 26 D) with narrowly rectangular median lobe with deep median fissure, semicircular lateral margins. Third maxilliped ( Fig. 33 C; Serène 1964b: fig. 18A) merus subquadrate, ischium subquadrate, slightly longer than merus. Proportionally short ambulatory legs ( Fig. 16 D), merus especially stout, broad, proportionally wide articles with acute tubercles along lower margins, particularly P2 merus. Chelipeds ( Figs. 16 D; 45E, F) subequal in length, heteromorphic in males; fingers of minor chela ( Fig. 45 F) subcircular in cross-section, scissor-like, cutting margins with small teeth; cutting margins of major chela of males ( Fig. 45 E) with short teeth, most proximal enlarged. Ventral surface of cheliped merus with outer, inner rows of tubercles, short teeth (about ten on outer margins, many on two rows along inner margins). Inner margin of cheliped carpus with short distal tooth ( Fig. 16 D). Fused thoracic sternites 1, 2 ( Fig. 54 D) semicircular, broad, short. Wide sternum. Male pleon ( Fig. 54 E; Serène 1964b: fig. 18B) with proportionally short telson. G1 ( Fig. 77 E‒G; Serène 1964b: fig. 18C) slender, distal segment slightly curved, with short spinules, pointed apex. G2 ( Fig. 77 H; Serène 1964b: fig. 18C) about 1/2 G1 length, slightly curved, distal segment proportionally short. Mature female unknown.

Remarks. Same wide sternum, pleon, mouth parts, and “supplementary plate” as in apta /pubescence. Proportionally shorter and thicker ambulatory legs than S. apta .

Distribution. Only known from New Caledonia. Depth: 165– 360 m.

Figures

FIGURE 16. Overall dorsal view, chela, ambulatory legs and pleon of species of Statommatia n. gen. A, S. apta, Philippines: holotype male 7.8 × 9.4 mm (USNM 46839); B, S. apta, Philippines: male 5.9 × 7.1 mm (ZRC 2015.239); C, S. apta, Philippines: female 8.5 × 10.6 mm (ZRC 2015.238); D, S. knudseni, New Caledonia: holotype male 4.7 × 6.9 mm (ZMUC CRU- 6974); E, S. malagasy n. sp., Madagascar: holotype male 9.9 × 12.4 mm (MNHN-IU- 2010 - 4370 a); F, S. malagasy n. sp., Madagascar: paratype female 9.4 × 8.1 mm (ZRC 2015.215); G, S. pubescens, South China Sea: holotype male 5.0 × 7.9 mm (after Chen 1998: fig. 23 - 1 ‒ 4, 6); H, S. granulosa n. sp., New Caledonia: holotype male 4.1 × 4.7 mm (MNHN-IU- 2013 - 9454).

FIGURE 26. Frontal view of species of Statommatia n. gen. and Tenagopelta n. gen. A, Statommatia apta, Philippines: holotype 7.8 × 9.4 mm (USNM 46389); B, Statommatia apta, Philippines: male 5.9 × 7.1 mm (ZRC 2015.239); C, Statommatia malagasy n. sp., Madagascar: holotype male 9.9 × 12.4 mm (MNHN-IU- 2010 - 4370 a); D, Statommatia knudseni, New Caledonia: holotype male 4.7 × 6.9 mm (ZMUC CRU- 6974); E, Statommatia granulosa n. sp., New Caledonia: holotype male 4.1 × 4.7 mm (MNHN-IU- 2013 - 9454); F, Tenagopelta pacifica n. sp., Philippines: holotype male 10.3 × 11.9 mm (NMCR); G, Tenagopelta brachyphallus n. sp., Australia: holotype male 6.1 × 6.9 mm (NMV J 61680); H, Tenagopelta potens, Papua New Guinea: male 11.8 × 13.8 mm (MNHN-IU- 2011 - 1504).

FIGURE 33. Third maxilliped of species of Statommatia n. gen. and Tenagopelta n. gen. A, Statommatia apta, Philippines: holotype male 7.8 × 9.4 mm (USNM 46389); B, Statommatia apta, Philippines: male 5.9 × 7.1 mm (ZRC 2015.239); C, Statommatia knudseni, New Caledonia: holotype male 4.7 × 6.9 mm (ZMUC CRU- 6974); D, Statommatia pubescens, South China Sea: holotype male 5.0 × 7.9 mm (after Chen 1998: fig. 23 - 5); E, Statommatia malagasy n. sp., Madagascar: holotype male 9.9 × 12.4 mm (MNHN-IU- 2010 - 4370 a); F, Statommatia granulosa n. sp., New Caledonia: holotype male 4.1 × 4.7 mm (MNHN-IU- 2013 - 9454); G, Tenagopelta pacifica n. sp., Philippines: holotype male 10.3 × 11.9 mm (NMCR); H, Tenagopelta brachyphallus n. sp., Australia: holotype male 6.1 × 6.9 mm (NMV J 61680); I, Tenagopelta potens, Papua New Guinea: male 11.8 × 13.8 mm (MNHN-IU- 2011 - 1504).

FIGURE 45. Chelae of species of Statommatia n. gen. and Notopelta n. gen. A, B, Notopelta mortenseni, Indonesia: holotype male 5.0 × 6.9 mm (ZMUC CRU- 7397); C, D, Statommatia apta, Philippines: male 5.9 × 7.1 mm (ZRC 2015.239); E, F, S. knudseni, New Caledonia: holotype male 4.7 × 6.9 mm (ZMUC CRU- 6974); G, H, Statommatia malagasy n. sp., Madagascar: holotype male 9.9 × 12.4 mm (MNHN-IU- 2010 - 4370 a); I, J, Statommatia granulosa n. sp., New Caledonia: holotype male 4.1 × 4.7 mm (MNHN-IU- 2013 - 9454).

FIGURE 54. Anterior thoracic sternum and male pleon of species of Statommatia n. gen. and Tenagopelta n. gen. A, Statommatia apta, Philippines: holotype 7.8 × 9.4 mm (USNM 46389); B, Statommatia apta, Philippines: male 5.9 × 7.1 mm (ZRC 2015.239); C, Statommatia malagasy n. sp., Madagascar: holotype male 9.9 × 12.4 mm (MNHN-IU- 2010 - 4370 a); D, E, Statommatia knudseni, New Caledonia: holotype male 4.7 × 6.9 mm (ZMUC CRU- 6974); F, Tenagopelta pacifica n. sp., Philippines: holotype male 10.3 × 11.9 mm (NMCR); G, Tenagopelta brachyphallus n. sp., Australia: holotype male 6.1 × 6.9 mm (NMV J 61680); H, Tenagopelta potens, Papua New Guinea: male 11.8 × 13.8 mm (MNHN-IU- 2011 - 1504).

FIGURE 77. Gonopods of species of Statommatia n. gen. A ‒ D, S. apta, Philippines: male 5.9 × 7.1 mm (ZRC 2015.239); E ‒ H, S. knudseni, New Caledonia: holotype male 4.7 × 6.9 mm (ZMUC CRU- 6974); I ‒ L, S. malagasy n. sp., Madagascar: holotype male 9.9 × 12.4 mm (MNHN-IU- 2010 - 4370 a). A ‒ C, ventral view of right G 1 [left one damaged]; E, I, ventral view of left G 1; B, dorsal view of distal part of right G 1; C, ventral view of distal part of right G 1; F, J, ventral view of distal part of left G 1; G, K, dorsal view of distal part of left G 1; D, H, L, left G 2. Scales: A, D, E, H, I, L = 0.5 mm; B, C, F, G, J, K = 0.1 mm.