A new species of Streblospio Webster, 1879 (Annelida: Spionidae) from the Caribbean Sea

We describe a new species of spionid polychaete, Streblospio papillaris sp. nov., from Chetumal Bay, Quintana Roo, in the Mexican Caribbean Sea. This new spionid species was recorded from shallow, muddy sediments in brackish waters. The new species is characterized by: presence of numerous papillae scattered throughout the body; absence of eyes; very long peristomium that extends to the anterior part of the prostomium; dorsal papilla on the dorsum of chaetiger 1; sabre chaetae from chaetiger 2; hooded hooks with 4 pairs of small secondary teeth on the anterior and middle segments, hooded hooks with 3 pairs of small secondary teeth on the posterior segments; and pygidium with two ventral lappets.

This is the third species of Streblospio known from the Caribbean Sea. An identification key and table with the most relevant characters of Streblospio species are provided.