51. Hydrophorus callostomus Loew, 1857

Material examined. 3♂, 2♀, Yakutia, Pokrovsk, 21.07.1986, V. N. Makarkin .

Distribution. Type locality: Russia, “Siberia.” Palaearctic: Armenia, Kazakhstan, Russia (Adygea, Buryatia, Dagestan, Krasnodar, Leningrad, Omsk, Primorye, “Ural,” Voronezh, Yakutia, Yaroslavl), Sweden, Tajikistan, Turkey, Ukraine.