Rhabdochona ictaluri sp. nov. (Nematoda, Rhabdochonidae) from ictalurid catfishes in Mexico.

A new species of Rhabdochona is described as a parasite of two endemic species of catfishes (Ictalurus dugesii and Ictalurus pricei) from two river basins in central and northern Mexico (Rio Ameca and Rio Tunal). Rhabdochona ictaluri sp. nov. is characterized by a combination of morphological traits that include the presence of basal teeth, bifurcated deirids, absence of a dorsal barb in left spicule and length ratio between spicules. The combination of these traits readily distinguishes the new species from all its congeners, including those species possessing 14 teeth in the prostom. The new species appears to be specific to freshwater ictalurids.