First Report of (Cestoda: Hymenolepididae) from in Iran: A Probable Fatal Case Due to Hyperinfection.

Cestodes are important parasites that can affect the health of humans and wildlife. Among these, the genus is an important endoparasite of Passeriform birds while poorly studied in Iran. During a parasitological field survey in central parts of Iran in 2018, thirty-two cestode, as an obstructive intertwined mass, recovered from the intestine of a recently dead (great tit). Morphological characteristics of recovered cestodes were drawn carefully by a camera lucida equipped microscope and identification was carried out using standard keys. All of the collected cestodes were identified as . In the current study, we recorded from great tit for the first time in Iran.