Isomermis benevolus sp. n. (Mermithidae, Nematoda), a parasite of Simulium metallicum (Diptera : Simuliidae) in Guatemala

Abstract

The nematode, Isomermis benevolus sp. n. (Mermithidae) is described as a parasite of Simulium metallicum Bell. (Diptera : Simuliidae) in Guatemala. This is the first mermithid described from a Central American vector of Onchocerca volvulus, causal agent of the River blindness disease. The terminal mouth, shape and size of the amphids and spicules and length of the vagina separates this species from all previously described members of the genus Isomermis. The parasite has been recovered from several localities in Guatemala.