Ammonoids (Desmoceratoidea and Silesitoidea) from the Late Barremian of Boljetin, eastern Serbia

The subject of the study was the taxonomy of the ammonite fauna from the Upper Barremian marls and marly limestones of the Donji Milanovac Formation outcropped at the Boljetin Hill (Danubicum Unit). These sediments yielded a rich ammonite fauna which included also representatives of two superfamilies, Desmoceratoidea and Silesitoidea. The Desmoceratoidea include the family Barremitidae to which belong Plesiospitidiscus boljetinensis n. sp., Barremites balkanicus, Montanesiceras breskovskii n. sp., Barremitites strettostoma strettostoma and B. panae, Torcapella serbiensis n. sp., Pseudohaploceras tachthaliae, P. portaeferreae, Melchiorites haugi and Patruliusiceras cf. crenelatum. The Silesitoidea are represented by the family Silesitidae with Silesites trajani and S. seranonis. With the exception of the new, possibly endemic species, Plesiospitidiscus boljetinensis n. sp., Montanesiceras breskovskii n. sp., and Torcapella serbiensis n. sp., these taxa are common in the Tethyan regions. The studied deposits with ammonites belong to the lower part of the Late Barremian, in particular to the upper part of the Toxancyloceras vandenheckii ammonite Zone up to the lower part of the Imerites giraudi Zone.