The first checklist of rotifers of Armenia

Armenia is located in the Caucasus Ecoregion, one of Earth's most biologically rich regions and ranked among the planet’s 36 most diverse hotspots. Although the country is home to a wide range of flora and fauna, much of its biological wealth has yet to be explored. This study aims to compile the first checklist of Armenian rotifer species with an indication of their sampling sites based on available literature data. The phylum Rotifera comprises about 2,000 species of tiny invertebrates that occupy key positions in aquatic ecosystems. The oldest available records of rotifers in Armenia date back 100 years. To date, 101 rotifers below the genus level (95 species and 6 subspecies) belonging to 35 genera and 21 families from the class Eurotatoria, orders Ploima (79 species and 6 subspecies), Flosculariaceae (10 species), Bdelloidea (5 species), and Collothecacea (1 species) have been recorded in Armenia. The highest number of rotifer species (69) has been reported from Lake Sevan. Similarities in species diversity of rotifers with neighboring countries are as follows: Turkey – 88%, Iran – 85%, Azerbaijan – 43%, and Georgia – 29%. Only 5 species recorded in Armenia were not found in adjacent countries. While the checklist of Armenian Rotifera provided in this article incorporates almost all available records, it needs to be completed by future studies, especially from the Ararat Valley, as well as the major rivers, high-altitude brooks, lakes, ponds, and marshes of the southern and northeastern parts of Armenia.