Ypsilothuria bitentaculata bitentaculata (Echinodermata: Holothuroidea) from the southwestern Atlantic, with comments on its morphology

Abstract

Ypsilothuria bitentaculata bitentaculata (Ludwig, 1893), previously known from several localities in the Pacific Ocean, is recorded herein for the first time from the southwestern Atlantic Ocean based on eight specimens caught off the coast of southeastern Brazil, between 505–511 m deep. Several morphological details are added to the description of Y. b. bitentacu­lata, including photographs of specimens and calcareous ring plates, as well as scanning electron microscope images of the ossicles from the body wall, oral and anal siphons and introvert. Additionally, Y. b. bitentaculata is compared to its congeners.