Pachycheles natalensis ( Krauss, 1843 )

Werding, Bernd & Hiller, Alexandra, 2007, The Porcellanidae (Crustacea: Decapoda: Anomura) of the Red Sea with description of a new species of Petrolisthes, Zootaxa 1460, pp. 1-24 : 4

3. Pachycheles natalensis ( Krauss, 1843)

( Fig. 3 )

Porcellana natalensis Krauss, 1843: 58 , pl. 4, figs. 1, 1a–c.

Pachycheles natalensis .— Sarojini & Nagabhushanam, 1968: 150, pl. 1, fig. 1.— Lewinsohn, 1969: 151, figs. 33a–c.— Ahmed & Mustaquim, 1974: 174.— Lewinsohn, 1979: 50.— Hogarth, 1988: 1100.— Tirmizi et al., 1989: 4, figs. 1a– h, 2.

Material examined. 27 ɗ, 17 Ψ (10 ov), 1 juv. ( SMNS ZIa 3370), Egypt, Red Sea, Koseir, leg. Klunzinger; 1 Ψ ( SMF 4686), Red Sea, leg. E. Rüppell; 1ɗ, 1 Ψ ( ZMB 2760), Red Sea; 2 Ψ (ov) ( ZSM 153/1), southern Red Sea, Massalla, Pola-Exp., 30 Dec. 1897.

Measurements. Largest ɗ 4.3 x 4.4 mm; largest Ψ 4.3 x 4.6 mm.

Remarks. Lewinsohn (1969) compared the characters of the species with those of P. garciaensis (Ward) . In both P. garciaensis and P. natalensis the form of the front and the chelipeds’ sculpturing seem to overlap. However, they can be distinguished from each other by the presence of fringes of feathered setae on the walking legs, present in P. garciaensis only. Also, P. natalensis shows a conspicuous tuft of setae in the gape of the fingers of the larger cheliped, considered by Lewinsohn (1969) as a constant feature in the material examined by him. Nevertheless, Haig (1966a) pointed out that this tuft of setae may be absent. Although this tuft was observed to be sporadically absent in the material examined here, it might be a good diagnostic character in larger series.

Distribution. Western Indian Ocean, including the Red Sea.

Figures

FIGURE 3. Pachycheles natalensis (Krauss, 1843), male, Egypt, Red Sea, Koseir (SMNS ZIa 3370).