Abstract
Three incomplete thecae of the stylophoran Lagynocystis cf. pyramidalis (Barrande, 1887) are described from the Upper Ordovician of the Baltic Paleobasin for the first time. These specimens of Lagynocystis are the first records of this genus from the Ordovician outside peri-Gondwana, thus significantly expanding its paleogeographical distribution of this genus. Due to the preservation of the specimens the microstructure of the stereom is studied for the first time in this genus.