On four new species of Cletocamptus Shmankevich, 1875 (Copepoda: Harpacticoida) from inland waters of Argentina

Argentinean specimens of Cletocamptus of the collection of the Smithsonian Institution as well as recently collected material were analyzed and four new species are described. Cletocamptus assimilis sp. nov. and C. tertius sp. nov. seem to be related to C. levis. Cletocamptus pilosus sp. nov. seems to be related to C. stimpsoni. Cletocamptus spinulosus sp. nov. shares the armature formula of the mandibular palp, the armature formula of P1–P4 and the lower insertion level of the innermost seta of the male P5BENP with C. levis, C. assimilis sp. nov. and C. tertius sp. nov. Cletocamptus spinulosus sp. nov. shares the slender seta of the maxillulary arthrite with C. pilosus sp. nov. and C. stimpsoni, and is unique in the strong spinules along the posterior margin of the P2- to P4-bearing somites. Additional comments on some other species and an identification key to the species of Cletocamptus are presented.