CONICET | Buscador de Institutos y Recursos Humanos

Ostracoda are small, bivalved crustaceans that abound in all types of marine and non-marine water bodies. Some species even occur in phytotelmata. Samples were collected with a pipette from Aechmea distichantha, Vriesea friburgensis (Bromeliacea) and Eryngium pandanifolium (Apiaceae) in three areas in the northeast subtropical region of Argentina between 2006 and 2009. Ostracods were dissected and valves stored dry in micropaleontological slides and with soft parts in glycerine in sealed slides. The new species characterized by the medium to large sized of the carapace. Females larger than males. Inner lamella well developed with cilia in the posterior part. The surface of carapace is smooth with few hairs. A1 with 5 segments, the first bearing a sub-apical ventral tiny seta. A2 dimorphic, terminal segment of male with a strong serrated claw. Mandibular coxal with 8 strong cuspate teeth. Second and third maxillular endites with two setae and two spatula-like claws each; palp not segmented, tapering, with two apical setae. Hemipenis with distal lobe triangular, with a pointed tip and a finger-like projection at the base of the internal margin, dorsal seta present near its basis; Lower Ramus present and shaped in a claspering process, copulatory process thick. Dorsal seta short and pointed inserted in a rounded base.Actually there are eight species within this genus from Southern of Brazil, Jamaica, Puerto Rico, Cuba, Honduras and South of USA. The new species resembles Elpidium martensi, E. bromeliarum and E. pintoi in shape and size of carapace, althought they have a very different morphology of the hemipenis.This is the first record of the genus Elpidium in Argentina and constitutes one extension of the distribution of the genus in South America being the most austral species of this genus and it is mentioned three new phytotelmata inhabited by ostracods in the Neotropical Region.