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The paper documents in detail the morphology, epidermal features and cuticle ultrastructure of the leaves of the Mesozoic conifer genus Anabarella Abramova 1984. For the first time, the leaf epidermal and cuticle structures of the type species Anabarella kryshtofovichii Abramova from the Albian–Cenomanian (Cretaceous) of the Anabar river basin (East Siberia, Arctic Russia) were studied with the scanning electron (SEM) and the transmission electron (TEM) microscopes. Emended diagnosis for the genus Anabarella and the diagnosis for the species A. kryshtofovichii are provided, since only a description of this species was given in the original publication. Because the holotype has been lost, a lectotype is selected. The cuticular membrane of Anabarella leaves belongs to the type 1 of the cuticle classification of Holloway 1982: it is made up of the cuticle proper A (composed of an outer polylamellate A1 layer and an inner homogeneous A2 layer) and a cuticular fibrillate layer B1. The leaves of Anabarella kryshtofovichii differ from other fossil conifers by a very thick cuticle membrane consisting predominantly of a cuticle proper A; the cuticular layer B1 is less than 1% from the total thickness of cuticular membrane in the ordinary epidermal cells. The studied leaves have both xeromorphic (thick cuticle and sunken stomata) and mesomorphic (amphistomatic leaves, unprotected stomata) features. The mesomorphic features of the Anabarella leaves, as well as the deciduousness, were probably an adaptation to the humid conditions of the mid-Cretaceous Arctic climate with warm and dark winters. • Emended generic diagnosis for Anabarella is provided. • A lectotype of Anabarella kryshtofovichii (the type species) is designated. • The leaf cuticle structure of Anabarella kryshtofovichii is studied by SEM and TEM. • The thickness and features of the cuticle layers are described. • Comparison of the Anabarella leaf cuticular structure with other conifers is done. [ABSTRACT FROM AUTHOR]