Two new palynomorph taxa are described, and several existing taxa are discussed from the Upper Jurassic‐Lower Cretaceous Byers Group of Livingston and Snow islands, South Shetland Islands, Antarctic Peninsula. Oligosphaeridium byersense sp. nov., a dinoflagellate cyst species, is found in the Valanginian interval of the Byers Group. Globorotundata acrita gen. et sp. nov., apalynomorph of unknown affinity, is areliable indicator of dysaerobia‐anaerobia and/or shallow marine paleoceanographic conditions, when present in moderate to high numbers. This paper includes the first description and discussion of focused ion beam milling preparation of palynological material.