A new species of Thaumastoderma (Gastrotricha: Macrodasyida: Thaumastodermatidae) is described from sublittoral sediments on the islands of Tobago (Trinidad and Tobago) and Carrie Bow Cay (Belize). Thaumastoderma ponticulus sp. nov. is similar to Th. ramuliferum and Th. cantacuzeni based on the presence of four pairs of dorsal cirrata tubes and a compound pair of spatulate tentacles. The main distinguishing characteristic is the presence of a fleshy bridge that interconnects the anterior and posterior spatulate tentacles on the head. Additional characters include the presence of two rows of anterior adhesive tubes, seven pairs of ventrolateral adhesive tubes, and five pairs of posterior adhesive tubes.