New materials on Ventalepis ketleriensis Schultze, 1980 extend the zoogeographic area of a Late Devonian vertebrate assemblage

Abstract

Newly collected and restudied earlier materials on an enigmatic fish Ventalepis ketleriensis Schultze, 1980  from the upper Famennian (postera – ? Lower expansa conodont zones) of Latvia and central and northwestern Russia support its porolepiform affinities. A new family Ventalepididae fam. nova is established for this genus upon a peculiar combination of characters, including scale structure and dermal bones ornamentation. New records extend the distribution of this genus and the Ventalepis vertebrate assemblage on the whole to a vast geographical zone along the south-eastern coast of the Old Red Sandstone continent. The habitat area of the Devonian vertebrate assemblage over such a large territory within the zoogeographical province of Baltica is established for the first time. Palaeozoogeographical analysis suggests Laurentian affinities of the Ventalepis assemblage demonstrating the major congruency to the Belgian and East Greenland ones. These and Russian localities are separated by a vast ORS continent. Presence of the dipnoan Jarvikia in all three locations, as well as an Ichthyostega-like tetrapod in the Belgian one reveals palaeozoogeographical connections, which might reflect possible dwelling not only in the near-shore continent periphery but also in the river systems of the continent itself.