Ennucula nipponica Smith, 1885 Shell medium, 11.7 mm in length, 8.6 mm in height, thin, and compressed; umbo acute and low; surface covered with yellowish periostracum; hinge plate thin; hinge teeth 17-20 on the anterior series and 7-8 on the posterior; chondrophore small, directed forwards; interior of shell pearly; inner ventral margin smooth. Distribution: East and South China Seas(44-80 m): Southern Japan Sea. Ecology: Vertical range from 44-1 350 m.