Nursia rhomboidalis ( Miers, 1879 )

Shih, Yi-Jia, Ho, Ping-Ho & Chan, Tin-Yam, 2015, Leucosiid crabs (Crustacea: Decapoda: Brachyura) from Taiwan, with three new records, Zootaxa 4052 (1), pp. 127-134 : 131

Nursia rhomboidalis ( Miers, 1879)

( Fig. 1 C)

Material examined. YiLan County: Dali. 1 female, 18.8× 13.9 mm, NMNS –L19930529, coll. Y.-F. Lee, 29 May 1993.

Remarks. Only one species of Nursia , N. plicata (Herbst, 1803) is known from Taiwan (Ng et al. 2001). This is surprising, especially considering the there are few species in nearby Japanese, Chinese and Korean waters (see Sakai 1976; Komatsu & Takeda 2001; Chen & Sun 2002; Lee et al 2009). The present record of N. rhomboidalis is noteworthy as this species is rarely reported. The species was described from Japan by Miers (1879) (as a species of Ebalia ) and was transferred to Nursia by Sakai (1976). Shen (1937) had described N. sinica from mainland China, but his species is clearly identical with N. rhomboidalis (see Dai et al., 1986: 60, pl. 7(3), fig. 30(1); Dai & Yang, 1991: 67, pl. 7(3), fig. 30(1); Chen & Sun 2002: 305, fig. 134, pl. 11(9)). After that, Lee et al (2009) had described this species by immature female from Korea, some characters differ from mature specimen had been described (see Lee et al., 2009: 289). Nursia rhomboidalis is unusual among congeners in having a pentagonal carapace with smooth anterolateral margins and smooth carapace surface that is divided into four parts by strong ridges. The genus Nursia in any case, is clearly heterogenous, and a revision is urgently needed to clarify the taxonomy of the several species-groups now recognised (see Komatsu & Takeda 1999, 2001, 2003).

Figures

FIGURE 1. A, Ebalia nudipes Sakai, 1963 (male, 11.8 × 12.1 mm, ZRC 2015.277); B, Galilia petricola Komai & Tsuchida, 2014 (male, 25.4 × 28.2 mm, NTOU – DW 4095); C, Nursia rhomboidalis (Miers, 1879) (female, 18.8 × 13.9 mm, NMNS – L 19930529); D, Myra fugax (Fabricius, 1798) (male, 26.2 × 35.7 mm, NTOU – L 20140424).