New geographical and host records of bed bug species of the genus Cimex L. (Hemiptera Cimicidae) are present in the article, and we also document and curate previously known data. In Russia, six species of the genus Cimex (C. dissimilis, C. hemipterus, C. hirundinis, C. lectularius, C. pipistrelli, C. sibiricus) are confirmed. Cimex pipistrelli are newly recorded for northern bat Eptesicus nilssonii and eastern water bat Myotis petax. C. lectularius was registered on greater noctule bat Nyctalus lasiopterus, Nathusius' pipistrelle Pipistrellus nathusii and Turanian serotine Eptesicus serotinus turcomanus for the first time. Our molecular data support the earlier assumption about a low level of genetic differences between C. pipistrelli and C. japonicus, which puts taxonomic status of C. japonicus into question. [ABSTRACT FROM AUTHOR]