Two new species of Choanocotyle Jue Sue and Platt, 1998 (Digenea: Choanocotylidae) from an Australian freshwater turtle (Testudines: Pleurodira: Chelidae).

Abstract

Choanocotyle hobbsi n. sp. and Choanocotyle juesuei n. sp. are described from the small intestine of the oblong turtle Chelodina oblonga from the vicinity of Perth, Western Australia. These are the third and fourth species referred to Choanocotyle. Choanocotyle hobbsi is most similar to Choanocotyle nematoides but differs in the size and shape of the oral sucker and the absence of a median loop in the cirrus sac. Choanocotyle juesuei is most similar to Choanocotyle elegans but differs in the size of the oral sucker and other morphometric criteria. Comparative analysis of the sequences of different nuclear ribosomal deoxyribonucleic acid regions of C. nematoides and C. hobbsi has confirmed that they are closely related but distinct species.