Earliest Silurian articulate brachiopods from central Kazakhstan
An abundant early Silurian brachiopod assemblage of 14 species, with strong affinities to the early Rhuddanian faunas of Britain and Baltoscandia, was recovered from ttre Akkerme Peninsula, on the western side of Lake Balkhash, southern Central Kazakstan. The occurrence of Stricklandia lens mullochensis, which is the earliest member of the Stricklandia-Costistricklandia lineage, dates this brachiopod assemblage as early Rhuddanian, within a stratigraphic interval from the Akidograptus acuminatus to the lower part of the Monagraptus cyphus graptolite biozones. Ttris is the first well documented record of early Rhuddanian brachiopods in Kazakhstan. The assemblage also includes Meifodia tulkulensis sp. nov. and Eospirifer cinghizicus with well preserved spiralia. The co-occurrence of Stricklandia lens mullochensis and Eospirifer cinghizicus has not been recorded previously and is regarded here as the most signiffcant difference between the early Rhuddanan brachiopod faunas of the Baltic (East-European) Plate and Britain; in contrast Eospirifer first appears in the two latter areas in the late Llandovery.
Key words: Brachiopoda, taxonomy, palaeogeography, Silurian, Rhuddanian, Kazakhstan.
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