PHYLOGENY OF HEXAMITA PARASITIC IN XENOCYPRINAE BASED ON CLADISTIC ANALYSIS OF MORPHOLOGICAL CHARACTERISTICS WITH CONSIDERATION OF COEVOLUTION BETWEEN HOSTS AND HOST-PARASITES

Based on 24 morphological characteristics, the phylogeny of Hexamita parasitic in Xenocyprinae was primarily illustrated through cladistic analysis. The results showed that the speciation of parasitic Hexamita was very late, and some characteristics, such as rod-like striahons were evolutionary character. Furthermore,based on the fauna of parasites, the phylogenetic relationship of Xenocyprinae was constructed. The results showed Distoechodon hupeinensis might be distinguished to the genus Xenocypris, and the origination of Pseudobrama simoni and D. tumirostris was earier.