Dipetalonema (Alafilaria) hydrochoerus subgen. et sp. n. (Nematoda: Filarioidea) from Colombian capybaras.

Dipetalonema (Alafilaria) hydrochoerus subgen. et sp. n. is described from specimens recovered from skeletal muscle fascia of the capybara, Hydrochoerus hydrochacris, from several localities in Colombia, South America. The microfilaria, which is found in the skin of the host, is also described for the first time. The monotypic species of the subgenus Alafilaria can be distinguished from existing Dipetalonema subgenera and all filariae known to us, on the basis of numerous preanal caudal papillae in males, small size of petals on the caudal extremity of each sex, and low, bluntly-rounded lateral alae in the cuticle of adult worms of both sexes. Unusual and distinctive features of the microfilaria include conspicuous lateral cuticular alae and a caudal extremity devoid of nuclei.