Description of three new species ofvon Nordmann, 1832 (Monopisthocotylea: Gyrodactylidae) onspecies (Nemacheilidae) from Qinghai-Tibet Plateau.

Abstract

Three new species ofs were identified from the body surface of thespecies from the Qinghai-Tibet Plateau,n. sp. onin northern Tibet,n. sp. onandandn. sp. onandin Lanzhou Reach of the Yellow River. The three newly identified species share the nemachili group species' characteristic of having inturning hamulus roots.n. sp. shared a quadrate sickle heel and a thin marginal hook sickle, two morphological traits that set them apart fromn. sp. However, they may be identified by the distinct shapes of the sickle base and marginal hook sickle point.n. sp. had much larger opisthaptoral hard part size than the other two species. The three new species show relatively low interspecific differences of 2.9-5.3% p-distance for ITS1-5.85-ITS2 rDNA sequences. Phylogenetic analysis indicated that the three new species formed a well-supported monophyletic group (bp = 99) with the other nemachili group species.