Studies on Mononchida of India. I. The genera Hadronchus, Iotonchus, and Miconchus and a revised classification of Mononchida, new order

Abstract

This is the first paper of the series on mononchs of India; it takes into account species of Hadronchus, Iotonchus, and Miconchus and it also deals with a revised classification of the group. Hadronchus andamanicus n. sp., has an apex of its dorsal tooth in posterior half of buccal cavity, mono-prodelphic gonad with a large posterior uterine sac, vulval papillae, caudal glands with terminal opening and a long filiform tail 6-10 anal body-widths long. Hadronchus shakili n. sp., is quite similar to H. andamanicus but has two ovaries. Iotonchus baqrii n. sp., is mono-prodelphic and unique in having large cuticularized pieces in the vagina at 9-12 µ from vulva. Iotonchus indicus n. sp., has two ovaries, basal dorsal-tooth, elongate-conoid tail 6-9 anal body-widths long and a subterminal opening to caudal glands. Miconchus dalhousiensis n. sp., has two ovaries, three equal sized basal teeth and tail about 4 anal body-widths long without caudal glands. Two known species, Iotonchus trichurus and Miconchus digiturus have also been recorded. A new order, Mononchida is proposed to contain the Bathyodontoidea (Clark, 1961) n. rank. and Mononchoidea (Chitwood, 1937) Clark, 1961. The superfamily Bathyodontoidea includes two families: Bathyodontidae Clark, 1961 and Mononchulidae (De Coninck, 1965) n. rank. The superfamily Mononchoidea includes the family Mononchidae Chitwood, 1937 and the following 4 new families and 2 new subfamilies: Mylonchulidae (Mylonchulinae and Sporonchulinae), Cobbonchidae, Anatonchidae and Iotonchidae.