Studies on trematodes and acanthocephalans from freshwater fishes of Hubei Province, central China, with the erection of a new genus Quadrihexaspiron gen. n. (Acanthocephala: Neoechinorhynchidae).

Abstract

The present paper comprises a systematic survey of trematodes and acanthocephalans based on helminthological examinations of 64 specimens of 14 species of freshwater fishes, belonging to six families of four fish orders, mostly from localities in Hubei Province, central China, collected in the autumn of 2002. A total of 15 trematode species (in 12 families) and 5 acanthocephalan species (in four families) was recorded. Almost all parasites are briefly described and illustrated and problems concerning their morphology, taxonomy, hosts and geographical distribution are discussed. Some findings represent new host and geographical records. New acanthocephalan genus Quadrihexaspiron gen. n. (Neoechinorhynchidae) is erected to accommodate two species from China, Quadrihexaspiron spinibarbi (Yu et Wang, 1997) comb. n. (type species) and Quadrihexaspiron parabramis (Yin et Wu, 1984) comb. n., originally placed in Hexaspiron Dollfus et Golvan, 1956; Hexaspiron is recognised as a genus belonging to Quadrigyridae. The trematode species Orientocreadium elegans Besprozvannykh, Ermolenko et Deveney, 2009 is considered to be possibly identical with Orientocreadium pseudobagri Yamaguti, 1934, whereas the morphologically similar acanthocephalan species Micracanthorhynchina dakusuiensis (Harada, 1938) and Micracanthorhynchina brevelemniscus Lisitsyna, Barčák, Orosová, Fan et Oros, 2023 may prove to be conspecific with Micracanthorhynchina motomurai (Harada, 1935). A re-examination of the type specimens of Neoechinorhynchus afghanus Moravec et Amin, 1978 (Acanthocephala), a parasite of fishes in Afghanistan, revealed the presence of minute trunk spines in this species and, consequently, it is transferred to the genus Quadrigyrus Van Cleave, 1929 (Quadrigyridae) as Quadrigyrus afghanus (Moravec et Amin, 1978) comb. n.