Abstract

A new genus Alatyroceras is established for the species A. nageli (Mitta) (type species of the genus), A. keuppi (Mitta), A. efimovi (Mitta), and A. infimum (Gulyaev et Kiselev), in Central Russia characterizing the interval correlated with the Upper Bathonian Variabile and Calyx zones of East Greenland. According to the refined data, the Keuppi Zone of the Russian Platform includes (from bottom to top) the efimovi, nageli, and keuppi faunal horizons. The genus Alatyroceras [M] completes the phylogenetic lineage Arcticoceras → Alatyroceras in the subfamily Arctocephalitinae; the name Costacadoceras Rawson is common to all microconchs of the subfamily.

中文翻译：

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阿拉特罗角属（Alatyroceras gen.）十一月（Ammonoidea：Cardioceratidae、Arctocephalitinae）来自俄罗斯地台上巴通统（中侏罗统）

摘要

在俄罗斯中部，为A. nageli (Mitta)（该属的模式种）、A. keuppi (Mitta)、A. efimovi (Mitta) 和A. infimum (Gulyaev et Kiselev)建立了一个新属Alatyroceras表征与东格陵兰上巴通阶变差区和花萼区相关的区间。根据精化数据，俄罗斯地台的Keuppi带（从下到上）包括efimovi、nageli和keuppi动物层。Alatyroceras属[M] 完成了Arctocephalitinae 亚科中Arcticoceras → Alatyroceras 的系统发育谱系； Costacadoceras Rawson这个名字是该亚科所有微型海螺的共同名称。