Chirocephalus sarpedonis sp. nov. (Branchiopoda, Anostraca, Chirocephalidae) from Turkey questions the monophyly of the traditional Chirocephalus species-groups

Chirocephalus sarpedonis sp. nov. (Anostraca, Chirocephalidae), collected in a temporary pond in Lycia (Turkey), is described and its affinities with the other species of the genus are investigated based on both morphology and mtDNA cytochrome oxidase subunit I (COI) sequences. Male and female morphology suggests its major affinity with the species belonging to the bairdi-group although the morphological peculiarities of the species make it difficult to ascribe C. sarpedonis sp. nov. to any of the Chirocephalus species-groups which are currently used in the systematics of the genus. Furthermore, molecular analyses based on the comparison with available Chirocephalus spp. COI sequences fail to confirm the monophyly of the bairdi-group and exclude C. sarpedonis sp. nov. from the spinicaudatus-group also. We thus refrain from assigning the new species to any of the existing Chirocephalus species-groups and highlight the need for a revision of the affinities and phylogeny of the species currently ascribed to the genus. In particular, the traditional Chirocephalus species-groups seem to be defined based on few, sometimes shared, characters, so that the definition of a new grouping of the species based on a combined morphological and molecular approach is desirable.