Chlorodiella xishaensis Chen and Lan, 1978

Shaga, I Bevin, Priya, K, Ramar, Selvakumar, Srinidhi, S, Mohan, G Chandra, Ranganathan, Sukanya, Moulvi, S M M & Mani, Bhuvaneswari, 2023, A Small Collection of Subtidal Crabs (Crustacea: Decapoda: Brachyura) from the Palau Islands Collected by Dredging, Bulletin of the National Museum of Nature and Science. Series A, Zoology 49 (1), pp. 7-42 : 24-26

Chlorodiella xishaensis Chen and Lan, 1978

( Figs. 9F , 10B–C )

Chlorodiella xishaensis Chen and Lan, 1978, p. 268 (in key), 271, 285, figs. 6, 7 (10–11), pl. 2 fig. 6.─ Serène, 1984, pp. 255 (in keys), 258, fig. 173, pl. 43 fig. E–F. ─ Dai et al., 1986, pp. 314 (in key), 319, fig. 169 (3), pl. 45 fig. 8.─ Dai and Yang, 1991, p. 338 (in key), 342, fig. 169 (3), pl. 45 fig.8.─ Davie, 2002, p. 519.─ Maenosono, 2022, p. 12, fig. 6.

Material examined. Off Kwannon , Koror I., Palau Is., dredged, with coralline algae; 1♂ (cb 4.6×cl 3.3 mm), 1 ♀ (9.1×6.0 mm), NSMT-Cr 30982; June 17, 1980; K. Baba leg. ─ Entrance to Toagel Mid in Arangel Channel, Babelthuap I., Palau Is., dredged, 30–40 m in depth, with coralline algae; 1 ♂ (8.0× 5.7 mm), NSMT-Cr 30983, 1 ovig.♀ (10.3× 6.9 mm), NSMT-Cr 30984; June 19 1980; K. Baba leg.

Remarks. Recently, Maenosono (2022) recorded seven Chlorodiella species from the Ryukyu Islands, with fine photographs, and discussed the precise identifications of the records in the literature. Chlododiella crispipleopa Dai, Yang, Song and Chen, 1986 , C. cytherea ( Dana, 1852) , C. laevissima ( Dana, 1852) , and C. xishaensis Chen and Lan, 1978 are generally close to each other, but the present knowledge shows the distinct differences are in the Gl morphology. As far as the present species, C. xishaensis concerned, the G1 is straight and directed forwards at the tip ( Fig. 10B ), differing apparently from the strongly curled tip in C. crispipleopa and C. cytherea , and the subtruncated tip armed with long recurved tubercles in C. laevissima . In the carapace of C. xishaensis , otherwise, the last anterolateral tooth (fifth including the external orbital tooth) is sharp, weakly curved forwards and similar, but slightly smaller than the preceding (fourth) tooth, while in the other species in question, the last tooth is small, obtuse and sometimes even vestigial, at the base of the preceding (fourth) tooth. The ambulatory legs ( Fig. 10C ) are stout and armed with a row of curved tubercles along the anterior margin of each merus, a terminal spine of the anterior margin of each carpus, and several teeth along the posterior margin of each dactylus.

Distribution. The reliable records are from Madagascar, Australia, the Xisha Islands, the Philippines, and the Ryukyu Islands, without intervening localities. New to the Palau Islands.

Figures

Fig. 9. A: Gaillardiellus rueppellii (Krauss), ♂ (NSMT-Cr 30985; cb 8.8×cl 6.6mm). B: Metaxanthops acutus Serène, ♂ (NSMT-Cr 30987; cb 6.8×cl 5.5mm). C: Lophoplax sextuberculata Takeda and Kurata, ovig.♀ (NSMT-Cr 30992; cb 5.2×cl 4.0mm). D: Vellumnus pygmaeus (Takeda), ♂ (NSMT-Cr 30994; cb 5.7×cl 4.5mm). E: Chlorodiella corallicola Miyake and Takeda, ovig.♀ (NSMT-Cr 30980; cb 4.8×cl 3.2mm). F: Chlorodiella xishaensis Chen and Lan, ♂ (NSMT-Cr 30983; cb 8.0×cl 5.7mm).

Fig. 10. A: Trierarchus squamosus (Stephenson and Hudson, 1957), ♂ (NSMT-Cr 30977; cb 12.6×cl 8.7mm). Front-orbital region in dorsal view. B–C: Chlorodiella xishaensis Chen and Lan, ♂ (NSMT-Cr 30983; cb 8.0×cl 5.7mm). Left G1 in ventral view (B) and right third ambulatory leg in dorsal view (C). D–F: Chlorodiella corallicola Miyake and Takeda, ♂ (holotype, ZLKU 1724; cb 6.6×cl 4.4mm). Distal part of right G1 in ventral (D) and sternal (E) views (original figures by Miyake and Takeda, 1968). Scales for A=5mm, B= 0.5mm, C=3 mm, F=0.5 mm.