Ciliopagurus Forest, 1995

Poupin, Joseph & Malay, Maria Celia, 2009, Identification of a Ciliopagurus strigatus (Herbst, 1804) species-complex, with description of a new species from French Polynesia (Crustacea, Decapoda, Anomura, Diogenidae), Zoosystema 31 (2), pp. 209-232 : 212-213

Genus Ciliopagurus Forest, 1995

DEFINITION OF THE “ STRIGATUS COMPLEX”

OF SPECIES

Morphological characters used to define this complex of species of Ciliopagurus are: 1) ocular acicle truncated and distally armed with 3-5 (rarely 2) terminal spines, instead of being acute with 1 or 2 (rarely 3) terminal spines as in other congeners; 2) relatively short ocular peduncles about 0.7 shield length; 3) relatively short distal segments of antennular peduncles about 0.25 shield length; 4) relatively low P3 dactyl/propodus ratio, about 1.05; and 5) use of narrow-apertured shells (e.g., Conidae or Olividae ), and a more flattened cephalothorax.

The four species in this complex are also remarkable in that they live in low intertidal and shallow waters only. Ciliopagurus strigatus is found from the low intertidal to about 20 m; C. tricolor is intertidal to subtidal, with the deepest record at 30 m; C. vakovako occurs from the intertidal to 10-20 m, with a single record at 53/ 57 m; and C. galzini n. sp. is from 3- 12 m. None of the other Ciliopagurus species are known from the intertidal area and most of them are usually found deeper than 50 m (see Forest 1995a: 131, fig. 30). In the depth range of 10-20 m Ciliopagurus krempfi Forest, 1952 , distributed from East Africa to central Pacific, could co-occur with the species of the “ strigatus complex”. However, intensive fishing investigations conducted with dredges and traps around the Marquesas Islands have shown that, at least in these islands, C. krempfi is a deep species located in the range of 74-252 m, and that it has been confused in shallower waters (0-57 m) with C. vakovako ( Poupin 2001) . It is therefore possible that the few unusual records of C. krempfi in the 10-20 m depth range (see Forest 1995a: 59; Hong Kong, 10 m and Moluccas Islands, 13-18 m) could in fact belong to a species of the “ strigatus complex”.

The distribution of Ciliopagurus shebae Lewinsohn, 1969 in Forest (1995a) was formerly limited to the West Indian Ocean, with a depth range of 55-90 to 90- 130 m. Recently, this species has also been reported from Japan and surrounding islands ( Kato & Okuno 2001; Okuno & Arima 2006; Okuno et al. 2006), with depth range between 20- 37 m. Therefore, it appears that the depth range of this species can also overlap with that of shallow water species of the “ strigatus complex”. However, according to Okuno (pers. comm.), C. shebae specimens collected in Japanese waters were obviously always deeper than those of C. strigatus , which are usually found between 5- 15 m.