The oldest species of ?Yavorskia (Tabulata) from the Upper Famennian of the Holy Cross Mountains (Poland)

A single perfectly preserved colony of a tabulate coral assigned tentatively to the genus Yavorskia Fomitchev, 1931, collected from Upper Famennian beds (Palmatolepis expansa conodont Zone) in a trench located north of the Kowala Quarry (Holy Cross Mts., central Poland) is here described as a new species, ?Y. paszkowskii sp. nov. It differs from other representatives of the genus in the lack of dissepimental structures and in smaller corallite diameters, and may therefore represent the ancestral taxon of this typically early Carboniferous genus. Yavorskia tabulates were apparently migrating eastwards along the southern margin of Laurussia and farther east and north towards Siberia, as they appear in the Famennian in Europe and in the early Carboniferous in the Altaides. Such a conclusion is consistent with previous observations on Early.Middle Devonian pleurodictyform tabulate distribution.