The nematode genus Haliplectus Cobb, 1913 (Chromadorea: Haliplectidae): phylogenetic relationships, description of a new species from the Persian Gulf, southern Iran, and a tabular key to valid species

Summary The family Haliplectidae is reported from Iran for the first time and Haliplectus iranicus sp. n., from a mangrove forest in the Persian Gulf, is described. The new species is characterised by one ventromedian supplement near to cloacal aperture and a group of three supplements, 10-15 μm anterior to cloacal opening, absence of protuberant caudal papillae and tail sexual dimorphism. A tabular key containing morphometric data and morphological information of 26 valid Haliplectus species is presented. Near full length SSU rDNA sequences are provided for H. iranicus sp. n. Our SSU analysis strongly indicates that Haliplectus does not belong to the order Plectida as in the current classification, and confirms the monophyly of Haliplectus based upon currently available data, but phylogenetic relationships of the genus remain uncertain. In fact, the classification of Haliplectidae is considered incerta sedis within the class Chromadorea.