A new species of Mesochra (Copepoda: Harpacticoida: Canthocamptidae) from a coastal system of northern Colombia with a key to the American species

Plankton samples obtained from the Laguna Navio Quebrado, La Guajira, northern Colombia, yielded the first record of the genus Mesochra Boeck, 1865 for Colombia. It is represented by an undescribed species, M. huysi sp. nov., which appears to be closely related to M. parva Thomson, 1946 and M. pseudoparva Gómez & Fiers, 1997. However, the new species can be distinguished from these two species by the insertion point of the inner seta of P1 ENP1, the length/width ratio of P1ENP, the inner seta of P1ENP2, the relative length of P3 and P4 ENP, by details of elements of P5 EXP female, the structure of the anal operculum, the remarkable ornamentation of the male P3 EXP1-2, the apophysis of the male P3 ENP2, and the claw-like or flame-shaped element of male P3 ENP3. This is the third record of a species of the genus from the Caribbean. A key to the 11 species of Mesochra known from the Americas is provided.