The largest Lower Devonian placoderm - Antineosteus rufus sp. nov. from the Barrandian area (Czech Republic)

Abstract

Antineosteus rufus sp. nov. from the upper Emsian of the Czech Republic is described based on two fragments of large dermal plates discovered in the Suchomasty Limestone. The original length of the animal is inferred to have exceeded that of Tityosteus rieversae - the largest Lower Devonian placoderm recorded so far. The occurrence of A. rufus in the Prague Basin is consistent with other giant homostiids in several areas. These animals were apparently adapted to plankton-feeding, although they appeared in the conditions of collapsed diversity of the planktic communities during the ``Devonian Nekton Revolution{''}. This successful feeding strategy made them the first vertebrates occupying the nutrient-rich ecospace producing the largest animals up to the present.