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Abstract An extraordinarily well-preserved autochthonous angiosperm herbaceous community is described from the Lower Cretaceous deposits of the Frentsevka Formation, southern Primorye, Far East of Russia. The locality Bolshoy Kuvshin is situated on the coast of the Ussuri Bay on the Bolshoy Kuvshin Cape near the town of Bolshoy Kamen. The plant-bearing layer was determined to be early - middle Albian in age. The angiosperm assemblage includes six species: Achaenocarpites capitellatus Krassilov et Volynets, Ternaricarpites floribundus Krassilov et Volynets, Jixia pinnatipartita S.X.Guo et G.Sun, Asiatifolium elegans G.Sun, S.X.Guo et Shao L.Zheng and two new undetermined species. The majority of specimens are represented by fragments of branching stems with attached leaves or fruits or by almost complete plants. Two species (Jixia pinnatipartita and Asiatifolium elegans) are also in the angiosperm assemblage from the Chengzihe Formation (eastern Heilongjiang, China). The angiosperm remains are accompanied by the fern Onychiopsis psilotoides which is represented by almost entire young plants. The plant fossils were buried during a single flooding event and remained very close to their original location. They formed a pioneer open herbaceous community, consisting of ferns and angiosperms with a predominance of the latter and adapted to colonize fresh sediments in periodically flooded areas.

The Cretaceous sections and plant macrofossils are investigated in detail near Vladivostok on the Muravyov Amurskii Peninsula of southern Primorye. It is established that the Ussuri and Lipovtsy forma tions in the reference section of the Markovskii Peninsula rest with unconformity upon Upper Triassic strata. The continuous Cretaceous succession is revealed in the Peschanka River area of the northern Muravyov Amurskii Peninsula, where plant remains were first sampled from the lower and upper parts of the Korkino Group, which are determined to be the late Albian-late Cenmanian in age. The taxonomic composition of floral assemblages from the Ussuri, Lipovtsy, and Galenki formations is widened owing to additional finds of plant remains. The Korkino Group received floral characteristics for the first time. The Cretaceous flora of the peninsula is represented by 126 taxa. It is established that ferns and conifers are dominant elements of the Ussuri floral assemblage, while the Lipovtsy Assemblage is dominated by ferns, conifers, and cycadphytes. In addition, the latter assemblage is characterized by the highest taxonomic diversity. The Galenki Assemblage is marked by the first appearance of rare flowering plants against the background of dominant ferns and coni fers. The Korkino floral assemblage is subdivided into two subassemblages dominated by different groups: conifers in the early and flowering plants in the late.

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