中国海滑蛤属Liocyma(双壳纲：帘蛤科)一新种

A NEW SPECIES OF LIOCYMA (BIVALVIA:VENERIDAE) FROM CHINA SEA

滑蛤属至今已发现的种都分布于北半球,这些种类都是冷水种。新种Liocyma chinensis是一个温水种,采自渤海莱州湾,这是滑蛤属在亚洲大陆最南的分布界线。新种的发现,增加了黄、渤海动物区系中的冷水性因素。

Boreal species of genus Liocyma distribute in the Northern Hemisphere. The new species of Liocyma chinensis is a temperate species collected from Laizhouwan Bay, Bohai Sea, where is the southernmost boundary of Asian mainland coast waters of genus Liocyma. The discovery of Liocyma chinensis increases the coldwater fauna elemental factor in the Bohai Sea. The description of the new species is given below： Liocyma chinensis sp. nov. （Figs. 1-3） Description： Shell very minute, equivalve, inequilateral. Umbo point, prosogyrate, a little anterior from the middle of dorsal margin. Anterior margin narrowly rounded and posterior magin obliquely truncated; from umbo to posterior margin with a obtuse ridge; The surface covered with a thin and light yellowish periostracum, and ornamented with irregular con- centric growth lines, which become rather coarse on the posterior slope, without lunule and escutcheon, and with brown sediments on the anterior and posterior of the umbo. Interior white, posterior adductor scar large and rounded, anterior one elongate and slightly flexed. Pallial sinus free, tongue in shape, reaching the centre of valve. Hinge plate thick, tree strong carchinal teeth in each valve; anterior cardinal tooth of right valve and posterior cardinal tooth of left valve with a longitudinal feeble groove, others all bifid. Holotype （LZW071001）： Collected by Leng Yu from intertide zone of Laizhonwan Bay （37°10′10.5″N, 119°10′45.9″E）, slit, October 5, 2007. Paratype （LZWO71002）： Collected from the same locality of Holotype. Etymalogy： The specific name chinensis is named after the type locality. Holotype is deposited at the Marine of Biological Museum, Chinese Academy of Sciences. Paratype is deposited at the North China Sea Environment Monitoring Center, State Oceanic Administration, Qingdao, China. Remark： This new species can be distinguished from the other species of Genus Liocyma by its smallness, less than 4mm in length, and with thick hinge plate and strong hinge teeth.