1. Department of Biological Sciences; University of Southern Mississippi; Hattiesburg MS 39401 USA
2. Laboratorio de Helmintología; Instituto de Biología; Universidad Nacional Autónoma de México; Apartado Postal 70-153 CP 04510 México D.F. México
3. LSU Museum of Natural Science (Ichthyology); Department of Biological Sciences; Louisiana State University; Baton Rouge LA 70803 USA
4. Department of Biology; University of Louisiana at Lafayette; Lafayette LA 70504-245 USA