The Moscovian stage was introduced by Sergei Nikitin (1850 - 1909) in 1890, using brachiopods in the Moscow Basin of European Russia. Nikitin named the stage after Moscow, then a major city and now the capital of Russia.
The base of the Moscovian is close to the first appearances of the conodontsDeclinognathodus donetzianus and Idiognathoides postsulcatus[2] or otherwise the fusulinidAljutovella aljutovica.[3] Because the fusulinid species are regionally different, they can not be used for worldwide correlation. A golden spike for the Moscovian stage has yet to be defined (2008). A proposal is to use the first appearance of the conodont Diplognathodus ellesmerensis, but since the species is rare and its evolution relatively unknown, it has not been accepted yet.[4]
The top of the Moscovian (base of the Kasimovian) is at the base of the fusulinid biozone of Obsoletes obsoletes and Protriticites pseudomontiparus, or with the first appearance of the ammonitegenusParashumardites.
Subdivisions
In European Russia and Eastern Europe, where the stage was first recognized, the Moscovian is subdivided into four regional substages: Vereiskian, Kashirskian, Podolskian, and Myachkovskian, named after towns near Moscow (Vereya, Kashira, Podolsk, and Myachkovo).
A genus of gephyrostegid reptiliomorph amphibian. A small animal, 22 cm in length, of generally lizard-like build and presumably habit. It had large eyes and a large number of small, pointed teeth, indicating it was an active insectivorous hunter.
Traditionally classified as a close relative of amniotes a later study found that it was more closely related to the amphibian group Lepospondyli. It measured around 45cm long.
^Gradstein, F.M.; Ogg, J.G. & Smith, A.G.; 2004: A Geologic Time Scale 2004, Cambridge University Press
^*Nemyrovska, T.I.; 1999: Bashkirian conodonts of the Donets Basin, Ukraine. Scr. Geol. 119, pp 1–115 (in Russian).
^*Solovieva, M.N.; 1986: Zonal fusulinid scale of the Moscovian Stage based on a revision of the type sections of intrastage subdivisions, Vopr. Mikropaleontol
^[1]Archived 2011-07-07 at the Wayback Machine a report by the taskforce to establish a Bashkirian-Moscovian boundary (Groves et al. (2008))
External links
Carboniferous timescale at the website of the Norwegian network of offshore records of geology and stratigraphy