Endemic and sub-endemic water beetles of Mongolia and their distribution ranges

The aim of this study was to compile a species list of endemic water beetles of Mongolia and determine their distribution patterns. A total of 1,179 individuals of endemic water beetles were collected from nine different sub-basins (123 sample points) throughout the country. Currently, 21 endemic and sub-endemic species have been recorded in Mongolia. Eight of these species were strictly endemic. The endemic and sub-endemic species were found only among four families: Dytiscidae (10 out 99 spp.), Gyrinidae (1 out 7 spp.), Helophoridae (5 out 16 spp.), and Hydraenidae (5 out 13 spp.). The rate of endemism was higher in Hydraenidae than other families (38.4%). Endemic beetle fauna was most similar between the Onon and Kherlen River Basins (80%). Helophorus parajacutus Angus, 1970 was common in five sub-basins, but Agabus kaszabi Guéorguiev, 1972, Gyrinus sugunurensis Nilsson, 2001 and Ochthebius mongolicus Janssens, 1967 were recorded from only one sub-basin. In terms of sub-endemic species, Mongolia was mostly similar to the fauna of Eastern Siberia, Russia (73.7%) than other neighboring regions. Due to Mongolia’s vast territory and different natural zones, endemism was exceptionally low (12.4%), but these data provide baseline information of endemic and rare species for their further conservation. KCI Citation Count: 0