Monogenean Parasites of some Elasmobranchs (Chondrichthyes) from the Yucatán Peninsula, Mexico

Forty-two individuals representing 8 species of stingray were collected from 14 localities along the coast of the Yucatán Peninsula in Mexico. Monogeneans from 2 families (Monocotylidae Lebedev, 1988 and Capsalidae Baird, 1853) were found on the gills and body surfaces. Dendromonocotyle octodiscus Hargis, 1955 was collected from Dasyatis americana Hildebrand and Schroeder, 1928 from Blanquizal, Quintana Roo, Mexico, and Urobatis jamaicensis (Cuvier 1816) McEachran and Fechhelm 1998 from Xcalak, Isla Contoy, Mexico, Cozumel, Quintana Roo, Mexico, and Ría Lagartos, Yucatán, Mexico. Decacotyle floridana (Pratt, 1910) Chisholm and Whittington, 1998 was collected from Aetobatus narinari (Euphrasen 1790) from Holbox, Quintana Roo, Mexico, and Ciudad del Carmen and Champotón, Campeche, Mexico. Benedeniella posterocolpa (Hargis, 1955) Yamaguti, 1963 was collected from Rhinoptera bonasus (Mitchell, 1815) from Champotón, Campeche, Mexico. Quintana Roo and Yucatán, Mexico, are new distribution records for D. octodiscus, and U. jamaicensis is a new host record for this species from a host collected from nature. Quintana Roo is a new locality record for D. floridana, and Campeche, Mexico, is a new locality record for B. posterocolpa. Hypotheses of biogeographical and coevolutionary patterns concerning monogeneans of elasmobranchs are premature, but B. posterocolpa seems to be strictly host specific, whereas D. floridana and D. octodiscus display a much lower level of host fidelity at lower host taxonomic levels.