Infection of the Isfahan tooth-carp, Aphaniusisfahanensis (Actinopterygii: Cyprinodontidae) with Diplostomumspathaceum (Trematoda: Diplostomidae): a case report.

Aphaniusisfahanensis is a new endemic killifish species that has been described in the Zayandeh River of the Isfahan basin in Iran. During a study on the biology of nine fish from this species, the parasite Diplostomumspathaceum was observed in the aqueous humor of the eye of a single individual. It was visible as a white mass with a diameter of 0.38 mm. This is the first report on the infection of A. isfahanensis with D. spathaceummetacercaria. They are pathogenic to fish and cause opacities in the optical lens (worm star) and blindness. Since A. isfahanensis is an endemic species, this discovery may be useful information to inform strategy with regards to the conservation of this fish.