New data on the morphology and age of the bryozoans of the genus Onychocella from the Campanian-Maastrichtian of Turkmenistan and Uzbekistan

The bryozoan of the collection from the Campanian-Maastrichtian of the Pitnyak group of uplifts in Turkmenistan and the central Kyzyl Kum Desert in Uzbekistan is revised. The bryozoan species, recently identified as Onychocella spinata Favorskaja, 1980 (order Cheilostomata), are shown to belong to two species: O. spinata and O. exilis sp. nov. The new species is described, and the original description of O. spinata is complemented. The nannofossil assemblage of the sediments of the Pitnyak Uplifts enclosing O. spinata is studied, that showed Lower Campanian age of, these sediments. Thus, O. spinata should have a wider stratigraphic range of Early Campanian-Late Maastrichtian. Since no nannofossils have been recorded in the sediments of the central Kyzyl Kum Desert enclosing O. exilis sp. nov., the stratigraphic range of this species should be restricted to the Maastrichtian.