Аннотация:The genus Duplexisporites was originally described by H. M. Deak in 1962 in grey clays of Hungary of the Aptian Age. This genus is characterized by specific anastomosing muri. Deak attributed it to subgroup Cingulati and pointed out the presence of a cingulum. Later G. Playford and M. Dettman (1965) redescribed the taxa of rounded-triangular forms with a rough ridge exine. They noted that the typical specimens illustrated by Deak had not been the cingulum. The authors kept the genus name of Duplexisporites, but changed its diagnosis. Moreover they moved this genus from subgroup Cingulati to subgroup Murornati.
There is also a similar genus Corrugatisporites which firstly was described by Thomson and Pflug (1953) with a single species (type species – Sporites solidus). Weyland and Greifeld (1953) added two species under name Corrugatisporites. Potonie and Kremp (1955) excluded C. solidus from this genus, and indicated the lectogenotype: C. toratus Weyland et Greifeld, 1953. Then Playford and Dettman (1965) demonstrated that the genus of Corrugatisporites was not valid according to IC (1961, art. 42). So, the genus name of Duplexisporites Deak, 1962, emend. Playford et Dettman, 1965 is the only valid name for rounded-triangular, acingulate spores with different muri. Hitherto, some authors use the diagnosis, given by Deak. They consider the genus Duplexisporites as forms having cingulum. Other palynologists understand the genus as it was described by Playford and M. Dettman (1965). Therefore there are a lot of confusions in literature concerning this genus. For example, Potonie (1966) took Duplexisporites to subgroup Cingulati. Potonie described new species of Duplexisporites, but this species is not valid for this genus. Shugaevskaya (1969) described ridge miospores from the Upper Mezozoic deposits. She modified the diagnosis of Duplexisporites and pointed out the presence of cingulum in the description. However the photos and schematic figures in her work did not confirm the presence of the cingulum. Shuurman (1977) distinguished a genus Asseretospora with typical species A. gyrata for the miospores of the Rhaeto-Liassic deposits of Australia. The diagnosis of the genus was completely identical to the diagnosis of Duplexisporites by Playford and Dettman. O. P. Yaroshenko (1978) studied the miospores of the Triassic of Western Caucasus and described Rotinella trisecta Maliavk., 1949. She included Duplexisporites gyratus to synonymy of Rotinella trisecta Maliavk. In such a way Yaroshenko wanted to restore priority of the genus of Rotinella. R. trisecta, represented by Maliavkina (1949), is similar to Duplexisporites gyratus. Because of Maliavkina (1949) did not describe Rotinella according IBC it is not valid.
Author of this paper undestand this genus Duplexisporites (Deak) Playford et Dettman as a acingulate miospores having distal and equtoria muri wich parallel equator of a spora.This work supported by The Russian Foundation of the basic Research (№ 04-05-64420).