Primer registro del Género Thelastoma Leidy, 1849 (Nematoda: Thelastomatidae) parasitando escarabajos pasálidos (Coleoptera: Passalidae) de Cuba

Abstract

The genus Thelastoma Leidy, 1849 (Nematoda: Thelastomatidae) is recorded for the first time parasitizing a passalid beetle (Passalidae) from Cuba. Such record is based in a single female specimen. It can be placed in the Group D following the classification of Barus & Boubková (2002) but differs by having larger body and eggs. Thelastoma sp. presents the tail comparatively shorter than the taxa from group D, with the exception of T. euscorpii Barus & Boubková, 2002. From the latter, also differs by having lateral alae, that are absent in T. euscorpii. The excretory pore of Thelastoma sp. is postbulbar vs. prebulbar in T. euscorpii. Moreover, the eggs of Thelastoma sp. present concave pits in the shell, instead of the smooth-shelled eggs of T. euscorpii. These differences suggest that Thelastoma sp. could belong to a new species. The discovery of only a single female specimen and the males that remain unknown, make necessary further collects in order to clarify the status of the taxon.