Cryptomya (Venatomya) sinensis ( Xu, 1987 )

Zhang, Jun-Long, Xu, Feng-Shan & Liu, Rui-Yu, 2012, The Myidae (Mollusca, Bivalvia) from Chinese waters with description of a new species, Zootaxa 3383, pp. 39-60 : 49

Cryptomya (Venatomya) sinensis ( Xu, 1987)

Figure 5A–F

Tugonia sinensis Xu, 1987: 438 , 441, fig. 1b—Bernard et al., 1993: 107; Xu, 1997: 230; Lutaenko & Xu, 2008: 52, text-fig. 6D; Xu & Zhang, 2008: 257, fig. 814; Xu, 2008: 589.

Cryptomya (Venatomya) sinensis ( Xu, 1987) — Huber, 2010:766.

Material examined. MBM 300741 (no.84M-185) (Holotype) (1 articutate shell), Huian, Fujian Province, China, on July 17th, 1984.

Distribution and habitat. Recent. East China Sea, Yellow Sea, China.

Type locality. Huian, Fujian Province, China. Habitat unknown.

Diagnosis. Length to 20 mm; shell laterally slightly compressed, thin and fragile; umbo prominent, situated slightly posterior, prosogyrate; sculpture of commarginal growth lines on anterior and anterorcentral shell, and radial ribs posterocentral to posterior, becoming more pronounced towards the posterior; posterior area lacking radial ribs; chondrophore in left valve shallow; pallial sinus shallow and broad, extending slightly beyond the posterior adductor scar; pallial line thin or obscure.

Remarks. The shell of this species is slightly compressed and its posterior end is not attenuated as is typical of Tugonia . Our present placement with Cryptomya (Venatomya) coincides with Huber (2010: 766); however, we do not agree with his synonymization with C. (V.) elliptica . Based on our examinations of type specimens of C. (V.) sinensis and material of C. (V.) elliptica , the shell of C. (V.) elliptica is much more compressed than that of C. (V.) sinensis . Comparing shells of similar size, C. (V.) sinensis (MBM 300741, Length = 19.0 mm) is much more fragile, the sculpture stronger, and the umbo much larger and more tumid than in C. (V.) elliptica (MBM136090, Length = 18.8 mm) ( Fig. 5 G).

Figures

FIGURE 5. A – F. Cryptomya (Venatomya) sinensis (Xu, 1987), holotype, MBM 300741, length = 19.0 mm. A. Exterior of right valve. B. Exterior of left valve. Scale bar (A, B) = 5 mm. C. Hinge of left valve. Scale bar = 2 mm. D. Interior of right valve. E. Interior of left valve. Scale bar (D, E) = 5 mm. F. Close up of surface sculpture. Scale bar = 2 mm. G. Close up of umbones of C. (V.) elliptica (left) and C. (V.) sinensis (right). Scale bar = 5 mm. H – M. Paramya recluzi (A. Adams, 1864). MBM 300739, length = 9.6 mm. H. Exterior of right valve. I. Exterior of left valve. Scale bar (H, I) = 2 mm. J. Hinge of left valve. Scale bar = 2 mm. K. Interior of right valve. L. Interior of left valve. Scale bar (K, L) = 2 mm. M. Close up of surface sculpture. Scale bar = 1 mm.