Integration of morphological and molecular data reveals further unknown diversity of the Proterodiplostomidae in crocodilians.

The Proterodiplostomidae Dubois, 1936 is a family of digeneans within the superfamily Diplostomoidea Poirier, 1886. Members of the family are distributed mostly in the tropics and subtropics, primarily in crocodilians, although some species are known from other reptiles. Despite their broad geographical distribution, the knowledge of proterodiplostomid diversity remains limited, mostly because a number of potential host species and regions of the world have not been sufficiently explored for these parasites. In this study, we use morphological and molecular data to describe four new genera ( gen. nov., gen. nov., gen. nov. and gen. nov.) and five new species ( sp. nov., sp. nov., sp. nov., sp. nov. and sp. nov.) of proterodiplostomids from crocodilians in Australia, South Africa and South America. gen. nov. has been established upon re-evaluation of the status of (Dubois, 1936) from caimans in Brazil using combined morphological and molecular evidence. Only a few previous studies provided DNA sequence data of proterodiplostomids. We generated partial 28S rDNA and cytochrome subunit (1) mtDNA for three previously undescribed proterodiplostomids collected from spp. in Australia and South Africa. The newly generated 28S sequences were used to examine phylogenetic affinities of these taxa. All three newly sequenced proterodiplostomid species appeared in the phylogenetic tree in a strongly supported monophyletic clade comprising exclusively parasites of .