Two New Species of the Genus Leptochiton (Mollusca, Polyplacophora) from North-Western Pacific

Two new species of the genus Leptochiton, L. commandorensis sp. nov. and L. incubatus sp. nov. from north-western Pacific are described. Leptochiton commandorensis differs from the congeners in having radial rows of granules in the lateral areas of intermediate valves, unicuspid dental cap on major lateral teeth of the radula, and dorsal scales with two ribs. Leptochiton incubatus differs from the congeners in having one aesthete pore in each granule, a shallow depression between the central and lateral areas of intermediate valves and between the antemucronal and postmucronal areas of the tail valve, and unicuspid head of major lateral teeth of radula. This species is brooding.