No abstract

Ischnacanthiform acanthodian dentigerous jaw bones from the Lower Morphology of the lingual tooth row is considered to be a diagnostic feature of generic and higher taxonomic levels, while accessory medial cusps/denticles of the teeth are regarded as diagnostic features at species level. The new genus also occurs in Upper Silurian or Lower Devonian deposits of North Greenland. Preservation of the jaw bones possibly depends on their secondary mineralization.Key words: Acanthodii, Ischnacanthiformes, dentigerous jaw bone, Devonian, Lochkovian, Podolia. Victor Voichyshyn [victor@museum.lviv.net], State Museum of Natural History NASU, Teatralna Str. 18, 79008, L'viv, Ukraine; Hubert Szaniawski [szaniaw@twarda.pan.pl], Instytut Paleobiologii PAN, ul. Twarda 51/55, Poland. This is an open-access article distributed under the terms of the Creative Commons Attribution License (for details please see creativecommons.org), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Investigation of fish fauna assemblages obtained by dissolution of calcareous rock samples from Early Devonian marine deposits of

The formation of the Early Devonian ichthyofauna occurred under the combined influence of historical, paleogeographic and paleoecological factors. A consequence of evolutionary development at the beginning of the Devonian period arose a number of high-ranking taxa of sea vertebrates, which actively colonized the shallow water basins of new continent Laurussia. For representatives of local endemic faunas there was an opportunity to expand their habitats. There were exchanges of migrants between neighboring regional faunas. All this was accompanied by the evolution of ecosystems, the formation and development of new ecological niches. Early Devonian for most groups of vertebrates was marked by a sharp increase in the number of taxonomic units. The formation of Podillya regional ichthyofauna illustrates these trends of global biotic changes in that time.