A new leptestiid brachiopod species of the genus Sampo and a hesperorthid species of the genus Dolerorthis are described from the Early Katian Oandu Stage of southern Lithuania. The new species Sampo suduvensis and Dolerorthis nadruvensis are common brachiopods for the Howellites wesenbergensis–Hedstroemina subaequiclina–Reushella magna community of the Lithuanian shelf. In the East Baltic the brachiopods of the genus Sampo appear first in the deeper part of the Lithuanian shelf in siliciclastic lithologies. The genus Dolerorthis is identified for the first time in the East Baltic. The new species Dolerorthis nadruvensis differs from other related Hesperorthidae brachiopods in the region. An exception is the Late Katian species Boreadorthis recula from Estonia, which shows similarity with D. nadruvensis in shell size and ornamentation. Still, the generic relationship of these species requires further studies. The new species of brachiopods are a supplement to the brachiopod fauna of southern Lithuania.
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