The life cycle of Mesostephanus indicum Mehra, 1947 (Digenea: Cyathocotylidae)

Abstract

The life cycle of the cyathocotylid fluke, Mesostephanus indicum Mehra, 1947 infecting the pariah kite, Milvus migrans govinda (Accipitridae), is elucidated. The species, reported by Mehra (Proc Nat Acad Sci India 17:1-52, 1947) from Buteo rufinus rufinus (Accipitridae), was transferred to the genus Prohemistomum by Dubois (Rev Suiss de Zool 58:639-691, 1951). However, it is retained in the genus Mesostephanus because of the presence of vaginal sphincter and caudal appendage, which are the characters of the genus. Its first intermediate host is the gastropod snail, Bellamya bengalensis (Viviparidae), which released the furcocercous cercariae. The prohemistomulum-type metacercariae encysted in the muscle tissues of the freshwater fish Rasbora daniconius and Puntius sophore (Cyprinidae), Mystus malabaricus (Bagridae), Heteropneustes fossilis (Heteropneustidae), Aplocheilus lineatus (Cyprinodontidae), Etroplus maculatus and E. suratensis (Cichlidae), and Pseudosphromenus cupanus (Belontidae). Recovery of M. indicum from M. m. govinda forms a new host record, and this is the first report of the life cycle of the genus from India.