The dracunculoid nematode Mexiconema cichlasomae Moravec, Vidal et Salgado Maldonado,
1992, originally described from the abdominal cavity and viscera of Cichlasoma spp.
from Mexico, was recorded from the abdominal cavity of the poeciliid Xiphophorus helleri
Heckel in Lake Catemaco and its small tributary Arroyo Agrio, Veracruz and from the
intestine of the nurse shark Ginglystoma cirratum (Bonnaterre) off the southern coast
of the Gulf of Mexico in Campeche; both these findings represent new host records.
The nematode specimens from these hosts are briefly described and illustrated. Whereas
X. helleri evidently served as the true definitive host of this parasite, G. cirratum
probably acquired Mexiconema infection accidentally while feeding on fish definitive
hosts in the brackish or salt-water environment. The ability of M. cichlasomae to
utilize fishes of different orders (Perciformes and Cyprinodontiformes) as definitive
hosts is rather exceptional among dracunculoid nematodes.