GENETIC-EVIDENCE INDICATING THAT COOPERIA-SURNABADA AND COOPERIA-ONCOPHORA ARE ONE SPECIES

Sequences of the second internal transcribed spacer (ITS-2) of ribosom al DNA were determined for the trichostrongylid nematodes Cooperia sur nabada and Cooperia oncophora, to test the hypothesis that they repres ent one species. Also included for comparison were other morphological ly distinct species within the genus, namely Cooperia punctata and Coo peria curticei. There were no differences in the consensus ITS-2 seque nces between C. oncophora and C. surnabada, whereas each taxon differe d from C. punctata and C. curticei by 1.7% and 4.1%, respectively. Als o, C. punctata differed from C. curticei by 5.0%. Based on these resul ts and the DNA studies of other trichostrongylid species, it is propos ed that C, oncophora and C. surnabada represent a single species. (C) 1998 Australian Society for Parasitology. Published by Elsevier Scienc e Ltd.