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A new fern Birisia mandshurica, sp. nov. (Dicksoniaceae) from the lower–middle Albian Frentsevka Formation of southern Primorye, Far East of Russia is described. This species is characterized by short-creeping rhizomes with closely spaced stipes and bipinnate fronds with narrow linear pinnules. A reconstruction of B. mandshurica is proposed. It comes from the autochthonous locality of ferns and herbaceous angiosperms and was a part of pioneer open community, which occupied low flat plains between river channels. Revision of ferns, described as Acanthopteris gothanii Sze from China, shows, that these ferns belongs to Birisia alata (Prynada) Samylina. The name Acanthopteris Sze should be abandoned, due to absence of spore-bearing pinnules and poor preservation of sterile pinnules in type specimens. Based on Chinese and Russian material of good preservation, we provide emended diagnoses of the genus Birisia Samylina and its type species B. alata. Re-examination of various species of the genus Birisia revealed that this genus was widely distributed in the Cretaceous floras (from the Barremian to the Coniacian) of Eastern Siberia, New Siberian Islands, North-East and Far East of Russia, China, Japan, Alaska and Western Canada. B. alata is the most widespread species.

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In the result of the re-examination of type material of the genus Birisia from the Cretaceous deposits of Siberia and North-East of Russia, we include only three species in this genus: B. alata (Prynada) Samylina (early-middle Albian — Coniacian), B. onychioides (Vassilevskaja et Kara-Mursa) Samylina (Aptian), and B. acutata Samylina (early-middle Albian). Species B. ochotica and B. alata are united under the name B. alata. Species B. jelisejevii, B. samylinae and B. oerstedtii are excluded from the genus Birisia as mismatching to the generic diagnosis. Species of Birisia are distinguished each other in size and degree of dissection of pinnules, in shape, presence and number of lobes, as well as the number of branches of the lateral veins inside the lobes. The pinnules of the Birisia are characterized by the significant variability and have a slightly different structure depending on their location on the leaf blade. Therefore, for a more accurate species identification of Birisia, it is necessary to have the most complete leaves with branching of two or three orders and the fertile pinnules.