Phylogenetic positions of the Bothitrematidae and Neocalceostomatidae (Monopisthocotylean monogeneans) inferred from 28S rDNA sequences

A molecular phylogeny was inferred from newly obtained partial (D1 domain) 28S rDNA gene sequences of Bothitrema bothi (Bothitrematidae), Neocalceostoma sp. (Neocalceostomatidae), Bravohollisia sp, (Ancyrocephalidae), and other already available sequences of Ancyrocephalidae, Anoplodiseidae, Pseudodactylogyridae. and Sundanonehidae, with the Diplectanidae as outgroup. Bothitrema, Anoplodiscus, and Sundanonchus formed a very robust clade that was the sister group to a group that included all other species examined. In this latter group. Neocalceostoma and Thaparocleidus were basal to a clade in which the Ancyrocephalidae and Pseudodactylogyridae were Sister groups. Molecular results that suggest inclusion of the families Bothitrematidae, Anoplodiscidae, and Sundanonchidae in the same group partially contradict a previous morphological analysis of Boeger and Kritsky in which the first 2 were placed in the Gyrodactylidea and the third in the Dactylogyridea.