Studies on ascaridoid nematodes in pythons: redefinition of Ophidascaris filaria and Polydelphis anoura.

Abstract

Host records, geographical distribution, and the taxonomy and synonymy, of the ascaridoid nematodes recorded as occurring in the python family, are presented. The evidence indicates that, besides Amplicaecum robertsi, which is so far reported only from Australian pythons, and possibly Hexametra quadricornis, there are two other distinct species which can be regarded as natural parasites of pythons, namely Ophidascaris filaria and Polydelphis anoura; these two species are described from specimens from Queensland pythons and compared with specimens from Africa and India. Perhaps it may eventually be established that further distinct species, or subspecies can be differentiated among the ascaridoid nematodes of pythons in different geographic areas, in addition to the above-named species. But it is suggested that the existing criteria for differentiation of other previously named species are not valid. Accordingly, it is proposed that the following specific names be reduced to synonymy within these two species respectively. Under O. filaria: rubicunda (male), infundibulicola, baylisi, and amucronata; ajgaris is a doubtful species. Under P. anoura: attenuata rubicunda (female), oculata, and bicornuta; mucronata is a doubtful species.Grateful acknowledgement is made of help, advice and co-operation on various aspects of this work which have been received from the following: Dr W. W. Becklund, Beltsville, Md.; Dr A. G. Chabaud, Museum National d'Histoire naturelle, Paris; Mr H. G. Cogger, The Australian Museum, Sydney; Dr G. Hartwich, Institut für Spezielle Zoologie und Zoologisches Museum, Der Humboldt-Universität zu Berlin; Dr W. G. Inglis, British Museum (Natural History); London; Dr P. Tate, University of Cambridge.The invaluable technical assistance of Ann McKeown and Marian Hollis is also gratefully acknowledged.This work was financed by a grant from the Australian Research Grants Committee.