Folia Parasitologica 46[4] 289-295 (1999)

Observations on cucullanid nematodes from freshwater fishes in Mexico, including Dichelyne mexicanus sp. n.

Juan Manuel Caspeta-Mandujano^1,2, František Moravec², Guillermo Salgado-Maldonado³

¹ Centre of Biological Research, Autonomous University of Morelos State, Av. Universidad No. 1001, Col. Chamilpa, C.P. 62210, Cuernavaca, Morelos, Mexico

² Institute of Parasitology, Academy of Sciences of the Czech Republic, Branišovská 31, 370 05 České Budějovice, Czech Republic

³ Institute of Biology, National Autonomous University of Mexico, A.P. 70-153, 04510 México, D.F., Mexico

A new cucullanid nematode, Dichelyne mexicanus sp. n., is described from the intestine of three species of fishes, Agonostomus monticola (Bancroft) (Mugilidae, Perciformes) (type host), Ictalurus balsanus (Jordan et Snyder) (Ictaluridae, Siluriformes) and Cichlasoma beani (Jordan) (Cichlidae, Perciformes), from three rivers (La Maquina River, Veracruz; Chontalcoatlán River, Guerrero and Santiago River, Nayarit) in central Mexico. This species is characterised by the absence of a ventral sucker in the male (subgenus Dichelyne) and it differs from its congeners mainly in possessing very unequal and dissimilar spicules (left 0.465-0.768 mm and right 293-548 mm long), an asymmetrical gubernaculum, and two intestinal caeca. Another cucullanid nematode, Cucullanus caballeroi Petter, 1977, is reported from Dormitator maculatus (Bloch) (Eleotridae, Perciformes) from the La Palma and La Maquina Rivers and Balzapote stream, Veracruz, being briefly described and illustrated; this represents a new host record. Findings of D. mexicanus and C. caballeroi represent a new record of cucullanid nematodes from fishes in Mexican fresh waters.

Keywords: Nematoda, Cucullanus, Dichelyne, freshwater fish, Ictalurus, Gobiomorus, Agonostomus, Cichlasoma, Mexico

Received: November 13, 1998; Accepted: May 20, 1999; Published: December 1, 1999  Show citation