ABSTRACT

The systematics of the family Pleurogenidae Looss, 1899, has been significantly revised in recent years, with the addition of 7 new genera based on molecular data. Despite these advancements, this family still lacks a definitive morphological synapomorphy. It encompasses genera with considerable morphological diversity, parasitizing a wide range of host groups across the globe. In the present study, we describe Parapleurogenoides n. gen., a new genus within the Pleurogenidae, discovered in the Levant water frog, Pelophylax bedriagae (Camerano, 1882), from the Sanandaj region of western Iran. This new genus is distinguished by its pyriform body shape, vitelline glands with a limited number of follicles, and a Y-shaped excretory vesicle. To investigate its phylogenetic relationships, a dataset of partial 28S rRNA sequences was generated, including all Pleurogenidae species available in GenBank. The phylogenetic analysis reveals that Parapleurogenoides kurdistanensis n. sp. and cercariae from Vietnam form a distinct clade, which is sister to Pleurogenes claviger (Rudolphi, 1819) and Pleurogenoides medians (Olsson, 1876). These clades are classified within Pleurogenidae, a family known for parasitizing amphibians. Moreover, the relationships within Pleurogenidae and the taxonomy of the genus Pleurogenoides Travassos, 1921, are re-evaluated based on morphological traits and the potential inclusion of other species previously assigned to this genus.