Taxonomic Status and Molecular Systematics of an Endemic Fish, Herklotsichthys lossei (Clupeidae) from the Persian Gulf: Insights into Non-monophyly of the Genus

Abstract

The endemic Persian Gulf herring, Herklotsichthys lossei, has similar characteristics with other congeners, especially H. punctatus, which makes it difficult to recognize. Freshly collected samples from the type locality of H. lossei assign morphologically to H. lossei, described by Wongratana in having a dark blotch on the dorsal fin and small dark spots on the flank. However, all the studied materials have a series of black spots along the back and both sides of dorsal–fin base which was not mentioned by Wongratana and was not found in the examined type materials deposited in Natural History Museum, London. Based on the available molecular data (mtCOI) for six species of Herklotsichthys, it is clear that the genus is not monophyletic. Herklotsichthys dispilonotus, H. punctatus and H. lossei make a sister lineage to other congeneric species including H. quadrimaculatus, H. lippa and H. spilurus and also with several phylogenetically distantly related genera Sardinella, Harengula, Amblygaster, Nematalosa, Anodontostoma, Alosa, Clupea and Clupeonella. This situation makes the taxonomic status of clupeid genera, especially Herklotsichthys more complicated. As H. dispilonotus the type species of the genus Herklotsichthys is nested with H. lossei and H. punctaus, these three species remain in the same genus and three others, H. quadrimaculatus, H. lippa and H. spilurus form a distinct genera.