A comparative morphological study of the subfamily Gastrodiscinae Monticelli, 1892 (Paramphistomidae) with comments on some members of related subfamilies

Abstract

The tegumentary papillae and histological structure of the pharynx, acetabulum and terminal genital ducts have been studied in Gastrodiscus aegyptiacus, Gastrodiscoides hominis, Homalogaster paloniae and Choerocotyloides onotragi and comparisons made with some species of Watsonius and Pseudodiscus. The generic diagnoses of Gastrodiscus, Watsonius, Gastrodiscoides and Homalogaster are emended. The subfamily Watsoniinae is considered synonymous with the Pseudodiscinae. The subfamily Choerocotyloidinae is considered valid and the subfamily Gastrodiscinae is retained, containing Gastrodiscus, Gastrodiscoides and Homalogaster. New types of pharynx, terminal genitalium or acetabulum are described in some species and amendments are made to the descriptions of some established types.