A new finding of Dactylioceratidae Hyatt ammonite (lower jurassic, Lower Toarcian) in the taurican flysch on the northern slope of the Kacha Uplift (Mountainous Crimea)

Background. The rocks of the Taurican series, which form the folded basement of the Crimean Mountains, are the most ancient stratified deposits in the mountainous Crimea. Their study has spanned over 230 years. The Taurican series is known for very rare fossils. New ammonite findings are essential for clarifying the relative age and detailed correlation of deposits.

Aim. To study the early Toarcian specimen of Peronoceras (Dactylioceratidae), newly found in Crimea.

Materials and methods. The specimen is an incomplete, deformed imprint containing a part of the shell core of a young Peronoceras sp. ind. Its preparation was performed mechanically; photography and processing of results were carried out using digital technologies. Before photography, the specimen was sprayed with ammonium chloride.

Results. The Lower Toarcian specimen of Peronoceras newly found in Crimea was studied in detail. The biostratigraphic significance of this finding was shown.

Conclusions. The Crimean specimen is possibly related to Peronoceras subarmatum (Young et Bird, 1822) with regular, widely spaced coarse ribs and fibulation already present on the inner whorls. Crimean strata containing Peronoceras sp. presumably occupy a higher position than those containing Dactylioceras cf. athleticum (Simpson, 1855), which is consistent with the biostratigraphic structure of the classic Toarcian section of Great Britain.

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