Velvet Revolution: Integrative Taxonomy of South Caucasian Eresus Walckenaer, 1805 (araneae, Eresidae), with Five New Species

This study is part of a series devoted to the systematic revision of the velvet spider genus Eresus Walckenaer, 1805 (Araneae: Eresidae) in Western Asia, and represents a milestone toward understanding the biodiversity of this group in the South Caucasus and adjacent territories. Currently, only three species of Eresus are known from the South Caucasus, although the presence of E. kollari Rossi, 1846 is highly questionable. Integrating both morphological data and COI barcoding results, we herein describe and illustrate five new species: E. albimarginatus Seropian and Zamani, sp. nov. (male), E. deminutus Seropian and Bulbulashvili, sp. nov. (male), E. gulliver Seropian and Arsenashvili, sp. nov. (male female), E. megobroba Seropian and Bulbulashvili, sp. nov. (male), all from Georgia, and E. tigrani Zamani, Seropian, Zarikian and Sz & udblac;ts, sp. nov. (male female) from Armenia and Azerbaijan (Nakhchivan Autonomous Republic). An updated phylogeny, incorporating 23 newly generated sequences, revealed eight distinct maternal lineages, four of which are formally recognized as species-groups. Previous South Caucasian records of E. kollari and E. tristis Kroneberg, 1875 are considered misidentifications and are, therefore, rejected. We provide a map of the known localities of South Caucasian Eresus species, based on examined material and data from social networking platforms.