A Review of the GenusNeoechinorhynchus(Acanthocephala: Neoechinorhynchidae) from Australia with the Description of Two New Species

Abstract

Abstract Eight species of Neoechinorhynchus were reported from Australian waters. Neoechinorhynchus vittiformis n. sp. is described from Eleutheronema tetradactylum (Shaw). It can be distinguished from all its congeners by the following combination of characters: long cylindrical trunk without cuticular plaques, globular proboscis, proboscis armature with the anterior circle of hooks larger with simple roots and the middle and posterior hooks the same size and smaller, short neck, lemnisci nearly equal, almost reaching the anterior testis which is more than half the length of the posterior testis. Neoechinorhynchus (Neoechinorhynchus) bryanti n. sp., described from Liza subviridis (Valenciennes), also with an elongated trunk, can be distinguished from its congeners by the combination of a wider anterior trunk without cuticular plaques, a relatively long conical neck, a subglobular proboscis having anterior hooks with manubria, the hooks becoming gradually smaller posteriorly, the lemnisci not reaching level of testes and the anterior testis being longer than posterior testis. Neoechinorhynchus sp. resembled Neoechinorhynchus aldrichettae Edmonds, 1971 but had a rectangular-shaped proboscis with larger anterior hooks. New host and locality records were presented for N. aldrichettae, Neoechinorhynchus (Hebesoma) agilis (Rudolphi) and Neoechinorhynchus tylosuri Yamaguti, 1939 . No additional specimens of either Neoechinorhynchus ningalooensis Pichelin and Cribb, 2001 or the species inquirenda, Neoechinorhynchus magnus Southwell and Macfie, 1925, were available for study. Of the 8 putative species listed here, 5 (N. [N.] bryanti, N. magnus , N. ningalooensis, N. vittiformis, and Neoechinorhynchus sp.) are endemic to Australian waters. By comparison with the North American fauna the Australian fauna was considered impoverished. The morphological and zoogeographical similarities within the group of 8 long, slender neoechinorhynchid species found in the African, Indo Malayan, and Western Pacific Regions, including the 3 found in Australia, may reflect a degree of evolutionary affinity.