Выпуск: 4 , Том: 26 , Год издания: 2018

Problems of the Boreal-Tethyan correlation of the lower Carnian and their potential solutions are discussed. The composition and distribution of ammonoids in the most representative sections of the upper part of the lower Carnian Substage in Northeast Asia, including the northern Okhotsk Region, northern Verkhoyansk Region, and the central part of Kotelnyi Island, are considered. For the first time, the Yakutosirenites armiger ammonoid zone is paleontologically substantiated, and its boundaries in the lower Carnian section in the basin of the Tikhaya River of Kotelnyi Island are defined. The composition of the ammonoid assemblage of the armiger Zone in the studied region is emended and supplemented. It contains, along with the local ammonoid taxa (Yakutosirenites armiger (Vozin), Arctophyllites okhotensis Konstantinov) and rare exotic species of southern origin (Siberioklipsteinia dagysi Konstantinov), the cosmopolitan genus Sirenites. The history of the study and the morphology of the genus Sirenites are considered, and data on its stratigraphic and geographic distribution are summarized.