Dionidid and raphiophorid trilobites from the middle Ordovician (Viruan Series) of Jämtland, central Sweden

Abstract Dionidid and raphiophorid trilobites are described from the middle Ordovician (Viruan Series) of Jämtland, central Sweden. The family Dionididae is represented by one genus, Dionide Barrande, 1847, and the family Raphiophoridae by five genera, Ampyx Dalman, 1827, Ampyxella Dean, 1960, Ampyxoides Whittington, 1965, Cnemidopyge Whittard, 1955 and Lonchodomas Angelin, 1854. Seven species are described and discussed. Three of these are new: Dionide jemtlandica sp. nov., Ampyxoides minor sp. nov. and Lonchodomas striolatus sp. nov.. The majority of the trilobites described are from the Andersön Shale, equivalent to the H. teretiusculus, N. gracilis and lowermost D. multidens Zones (upper Llanvirn and lower Caradoc), and the Örån Shale, equivalent to the lower D. dingani and the uppermost D. multidens Zones (middle Caradoc). Meraspid and early holaspid material of D. jemtlandica is described.

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