Revision of the aphid subgenus Ramitrichophorus Hille Ris Lambers of genus Macrosiphoniella (Hemiptera, Homoptera: Aphididae, Macrosiphini), with redescriptions of all known species and identification keys.

Revision of the aphid subgenus Ramitrichophorus of genus Macrosiphoniella with redescriptions of all known species has been made. Geographical points of species registrations are listed. All known data on the biology of the studied species have been specified and analyzed. It was established that Macrosiphoniella (Ramitrichophorus) paradoxa (Bozhko, 1957) (syn. n.) is a synonym of Macrosiphoniella (Ramitrichophorus) hillerislambersi Ossiannilsson, 1954. It was confirmed that Macrosiphoniella nikolajevi Kadyrbekov, 1999 does not belong to the subgenus Ramitrichophorus. The first descriptions of males and oviparous females of M. (R.) hillerislambersi and M. (R.) medvedevi (Bozhko, 1950), and also alate viviparous females and oviparous females of M. (R.) janckei Brner, 1939 are given. Identification keys to the species of the subgenus is proposed. A possible way of the formation of the subgenus and the speciation that took place in it are discussed.