Abstract
Echinoderes ohtsukai sp. nov. is described from an intertidal flat in the Seto Inland Sea, Japan, based on observations with light and scanning electron microscopy. Echinoderes ohtsukai is characterized by 1) a short middorsal spine on segment 4; 2) lateroventral tubules on segments 5 and 8; 3) short laterodorsal tubules on segment 10; 4) a trunk 315-395μm long; 5) a lack of lateral terminal accessory spines in both sexes; and 6) lateral terminal spines of about 50% trunk length. The species has modified type-II glandular cell outlets, which have previously been reported among congeners only in E. rex Lundbye, Rho and Sorensen, 2011 from the Korea Strait.
