Abstract 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.

中文翻译：

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来自东西伯利亚（俄罗斯）北部白垩纪的 Anabarella Abramova (Pinopsida) 的叶子

摘要 本文详细记录了中生代针叶树属 Anabarella Abramova 1984 叶片的形态、表皮特征和角质层超微结构。用扫描电子 (SEM) 和透射电子 (TEM) 显微镜研究了阿纳巴尔河流域（东西伯利亚，俄罗斯北极地区）的白垩纪。提供了对 Anabarella 属的修正诊断和对 A. kryshtofovichii 物种的诊断，因为原始出版物中只给出了对该物种的描述。因为正模已经丢失，所以选择了正模。Anabarella 叶的表皮膜属于 Holloway 1982 表皮分类的第 1 类：它由表皮固有层 A（由外层多薄片 A1 层和内层均质 A2 层组成）和表皮原纤维层 B1 组成。Anabarella kryshtofovichii 的叶子与其他化石针叶树的不同之处在于非常厚的角质层膜，主要由角质层 A 组成；表皮层B1占普通表皮细胞表皮膜总厚度的不到1%。所研究的叶子具有异形（厚的角质层和凹陷的气孔）和中形（两性叶，未受保护的气孔）特征。Anabarella 叶子的中形态特征以及落叶性可能是为了适应白垩纪中期北极气候的潮湿条件，冬季温暖而黑暗。