First Report of Intestinal Cestode Infection in a Berylline Hummingbird (Saucerottia beryllina) in Mexico.

Background: Up to now, five cestode species have been reported infecting five hummingbird species. To date, there have been no reports of cestode infections in hummingbirds in Mexico.

Methods: A Berylline hummingbird (Saucerottia beryllina) was found dead in a backyard at Toluca City, Mexico, and a window collision was assumed as the cause of death. The bird was preserved in 10% neutral buffered formalin for routine histological examination.

Results: At the histological study, liver parenchymal disruption was observed. This lesion could be the result of the assume collision. No lesions were observed in other tissues examined. Conspicuous cestode structures were observed in the lumen of the small intestine. Structure of cestodes, as revealed from histological sections, suggests their position in the genus Anonchotaenia Cohn, 1900 (family Paruterinidae).

Conclusion: This is the first report of intestinal cestodosis in a Berylline hummingbird (S. beryllina) in Mexico.