Nuculu izushotoensis (Okutani, 1966)Shell stout, thick, veneriform, equivalve, inequilateral, 15.2 mm in length, 11.5 mm in height; umbo small, inclined posteriorly; surface covered with olive- coloured periostracum; anterior portion almost twice longer than the posterior; surface ornamented with numerous concentric ribs and feeble radial threads; inner surface with silverly lustre; ventral margin crenulated; hinge plate thick; anterior teeth about 18-20, posterior teeth about 10; chondrophore small, oblique. Distribution: East China Sea; Japan. Ecology: Known records range from the depth of 1940-2 800 m.