Abstract

Analysis of taxonomically significant trait variability in the genus Arcticoceras (Cardioceratide, Arctocephalitinae) enables the assignment of most species of this genus (including A. harlandi) identified earlier and characteristic of the lower Bathonian to the group of synonyms of A. ishmae. Invalidity of the genus Greencephalites is substantiated, and it is proposed to consider the species of this genus as cadiconic morphs of various Arctocephalites and Arcticoceras species. Revision of the genus Arcticoceras enables the abolition of the Harlandi Zone present in the biostratigraphic scales of various regions of the Arctic. The infrazonal volume of the Ishmae Zone of the Boreal (Arctic) standard includes at least three biohorizons, for which the A. ishmae subspecies can be used as indicators.

中文翻译：

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北极属类，1924年（Ammonidea）和北方地区下巴东期的地层生物地层学

摘要

分析大Arc属（Arcticoceras）（Cardioceratide，Arctocephalitinae）的分类学上显着的性状变异性，使该属的大多数物种（包括A. harlandi）能够更早地被发现，并具有较低的Bathonian特征，从而被赋予了A. ishmae同义词。属无效Greencephalites属实，并建议考虑本属各种的cadiconic变种的物种Arctocephalites和Arcticoceras种。修订Arcticoceras属能够废除北极各个地区生物地层规模中的哈兰迪区。北方（北极）标准品的伊斯梅带的次区域体积至少包含三个生物地平线，伊斯玛木霉亚种可以用作指示剂。