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Cherts, radiolarites, and radiolarian cherts are one of the most important components of accretionary complexes, and much used in the reconstruction of imbricated sections of ocean plate stratigraphy, and of the palaeogeographic and tectonic settings of ophiolitic mélanges. There has been little research on radiolarian cherts in the Kyrgyz South Tianshan, and the tectonic setting and temporal framework of the South Tianshan ocean are controversial. Here, we report well‐preserved radiolarians in ribbon‐bedded cherts in an ophiolitic mélange of the Atbashi accretionary complex (South Tianshan, Kyrgyzstan), which provide key evidence of ambient Palaeozoic oceanic conditions. The hydrofluoric acid technique was used to extract from the cherty rocks siliceous radiolarian, which yielded an age of late Early Carboniferous. Analyses of major, trace, and rare‐earth elements of four cherts indicate they are biogenic and deposited with little hydrothermal influence in a hemipelagic to continental margin environment. Our fossil ages and geochemical results of the radiolarian cherts from the Atbashi accretionary complex indicate that the South Tianshan ocean was still open in the Late Carboniferous, implying that it was a wide, long‐lived, major ocean that closed by northward subduction. [ABSTRACT FROM AUTHOR]

Moderately well-preserved radiolarian assemblages are described from bedded cherts south of Mae Hong Son, north-west Thailand. Twenty species and subspecies are identified, including one new species ( Archocyrtium sashidai Feng sp. nov.). The assemblages belong to the middle Early Carboniferous Albaillella indensis and Eostylodictya rota zones. The new data suggest that there was a pelagic basin between the Shan-Thai terrane and Gondwana during the Early Carboniferous. This implies, contrary to previous interpretations, that the Shan-Thai terrane had already rifted apart from Gondwana during the Early Carboniferous. [ABSTRACT FROM AUTHOR]