Deliberations on the problems of mammomonogamus species (Nematoda, Syngamidae) in ruminants.

The taxonomy of mammomonogamids parasitic in ruminants is discussed with regard to their different rates of variability in Cuba and Mexico. Since their variability is large and the existence of biological species is not based on their morphology but on the reproduction isolation of populations, the authors came to the conclusion that the specific analysis of mammomonogamids will be convincing only in case that it is carried out using taxonomic experiments of special orientation.