Redescription of <i>Enhydrosoma lacunae</i> Jakubisiak, 1933 (Copepoda, Harpacticoida); with comments on the <i>Enhydrosoma</i> species reported from West Atlantic localities, and a discussion of cletodid development

Thus far, 16 species of the cletodid genus Enhydrosoma have been reported from localities in the West Atlantic. Reexamination of these records revealed the following: (1) Cletodes stylicaudatus Willey, 1929 should be assigned to the genus Stylicletodes and quoted as Stylicletodes stylicaudatus (Willey, 1929); (2) the Patagonian specimens identified as Enhydrosoma propinquum by Pallares (1975) represent an unknown species, named hereafter Enhydrosoma rosae sp. n.; (3) E. propinquum reported from North Inlet Estuary (South Carolina) turned out to be a different and unknown species and should be referred to as Enhydrosoma spec.; (4) additional, comments on the male juvenile features of E. nicobaricum Sewell are given. Following these amendments, E. lacunae Jakubisiak is redescribed based on material from Celestún Lagoon (Yucatan, Mexico). E. woodini Thistle is considered a junior synonym of E. lacunae. There seem to be sufficient reasons to consider the Brazilian species, E. mangroviae Jakobi and E. gerlachi Jakobi as junior synonyms of E. lacunae. Finally, the copepodid development of E. lacunae is described. The segment additions in the ramal development are compared with Cletodes. The heterochronic development resulting in the unique segmentation of the exopodal rami of Enhydrosomella is discussed and the homology of the male P3 dimorphic apophysis in Cletodidae is reconsidered