Euhaplorchis californiensis Martin, 1950

Scholz, T., Aguirre-Macedo, M. L. & Salgado-Maldonado, G., 2001, Trematodes of the family Heterophyidae (Digenea) in Mexico: a review of species and new host and geographical records, Journal of Natural History 35 (12), pp. 1733-1772 : 1758

* Euhaplorchis californiensis Martin, 1950

Metacercaria

Morphology. No data are available.

Second intermediate host. Fundulus grandissimus (Cyprinodontidae) .

Site of infection. Brain.

Distribution. YucataÂn (CheleÂm).

References from Mexico. Present study.

Specimens deposited. None.

Comments. During a study on the parasites of ®sh from the CheleÂm lagoon near Progreso, YucataÂn, carried out in January 1994, heterophyid metacercariae were found in the brain of four of 15 Fundulus grandissimus (mean intensity 9 metacercariae; range 5± 16 specimens). Metacercariae ®tted in their morphology, in particular the presence of a conspicuous, pyriform gonotyl armed with anteriorly directed sclerites and the site of infection, into the diagnosis of the species Euhaplorchis californiensis described by Martin (1950a) from the brain of Fundulus parvipinnis in California.

In November and December 1999, 37 F. grandissimus from the same locality were examined but no metacercariae were found. Since no specimens found in January 1994 were preserved, no description, measurements or illustrations based on Mexican material are provided in this paper. Fundulus grandissimus represents a new second intermediate host of the trematode that is reported from Mexico for the ®rst time.

Martin (1950a) described the life cycle of this trematode, reporting the prosobranch snail Cerithidea californica , harbouring rediae and oculate, parapleurolophocercous cercariae, to serve as the ®rst intermediate, and chicks and Californian gull ( Larus californicus Lawrence ) as experimental de®nitive hosts, respectively.