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

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: Acharax
frenademezi sp. nov., Bakevellia (Bakevellia) preromangica sp. nov.,
Edmondia hautmanni sp. nov., Etheripecten stuflesseri sp. nov., Ladinomya
fosteri gen. et sp. nov., Lovaralucina covidi gen. et sp. nov., Palaeolima
badiotica sp. nov., Promytilus merlai sp. nov., Tambanella?
stetteneckensis sp. nov., Volsellina carinata sp. nov., Gardenapecten gen.
nov., Ladinomyidae fam. nov. The occurrence of three Eumorphotis species
with a different and superimposed stratigraphic distribution led us to
propose an upper Permian ‘lower Eumorphotis Zone’ in contrast to the
already known Lower Triassic Eumorphotis Zone which is consequently
renamed as ‘upper Eumorphotis Zone’. The ‘lower Eumorphotis Zone’ is
divided, in ascending stratigraphic order, into E. praecurrens, E.
striatocostata and E. lorigae subzones. 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.