Data from: Bivalves from the Changhsingian (Upper Permian) Bellerophon Formation of the Dolomites (Italy): ancestors of the Lower Triassic post extinction benthic communities

<p><span>The diverse shallow marine fossil assemblages from the Changhsingian Bellerophon Formation of the Dolomites record the late Palaeozoic marine life immediately before the end-Permian mass extinction. Here, based on the collection of c. 6500 bivalve specimens from different localities of the western Dolomites, we have taxonomically classified 26 species, including 10 new species, 3 new genera and 1 new family: <em>Acharax</em> <em>frenademezi</em> sp. nov., <em>Bakevellia</em> (<em>Bakevellia</em>) <em>preromangica</em> sp. nov., <em>Edmondia</em> <em>hautmanni</em> sp. nov., <em>Etheripecten</em> <em>stuflesseri</em> sp. nov., <em>Ladinomya</em> <em>fosteri</em> gen. et sp. nov., <em>Lovaralucina</em> <em>covidi</em> gen. et sp. nov., <em>Palaeolima</em> <em>badiotica</em> sp. nov., <em>Promytilus</em> <em>merlai</em> sp. nov., <em>Tambanella</em>? <em>stetteneckensis</em> sp. nov., <em>Volsellina</em> <em>carinata</em> sp. nov., <em>Gardenapecten</em> gen. nov., Ladinomyidae fam. nov. </span><span>The occurrence of three <em>Eumorphotis</em> species with a different and superimposed stratigraphic distribution led us to propose an upper Permian 'lower <em>Eumorphotis</em> Zone' in contrast to the already known Lower Triassic <em>Eumorphotis</em> Zone which is consequently renamed as 'upper <em>Eumorphotis</em> Zone'. The 'lower <em>Eumorphotis</em> Zone' is divided, in ascending stratigraphic order, into <em>E. praecurrens</em>, <em>E. striatocostata</em> and <em>E. lorigae</em> subzones. </span><span>A palaeoecological analysis of the bivalves contained in each sampled bed has allowed us to recognize 6 biofacies and 4 ecofacies, based on richness, dominance and ecological lifestyle. The bivalves from Bellerophon Formation inhabited lagoonal to nearshore environments affected by stressed conditions, mostly represented by high temperatures, high salinity, shallow water depths, low oxygen and high terrigenous input. The upper Bellerophon Fm is characterized by increasing fully marine conditions, although the occurrence of eurytopic taxa still suggests stressed marine conditions.</span></p>