D. Bassi et Cl. Broglio, Alveolinids at the Middle-Upper Eocene boundary in northeastern Italy (Veneto, Colli Berici, Vicenza), J FORAMIN R, 29(3), 1999, pp. 222-235
The Middle and Upper Eocene successions of the Colli Berici (Veneto, northe
astern Italy) have been studied since the beginning of the nineteenth centu
ry in order to describe the large, benthic foraminiferal-rich assemblages,
The Bartonian-Priabonian exposures in the southeastern part of the Colli Be
rici (Mossano) have been the proposed "parastratotype" for the Priabonian s
tage. The classic Mossano section and two additional sections outcropping i
n this area, all spanning the Calcari Nummulitici (Middle Eocene)-Marne di
Priabona (Late Eocene) formations, provided us with new biostratigraphic da
ta about two alveolinid species, Borelis vonderschmitti (Schweighauser) has
so far been recorded in the Colli Berici (type locality Cava Zengele) with
in the Bartonian part of the Calcari Nummulitici formation, and possibly in
the Priabonian of Italy and Slovenia, This taxon is herein described from
Mossano, and the associated larger foraminifera (Nummulites biedai) confide
ntly establish the age of these beds as Late Bartonian (SBZ 18), enabling t
he stratigraphic distribution of B. vonderschmitti to be extended to the ba
se of SBZ 18.A new species of Glomalveolina Hottinger 1960, G. ungaroi n. s
p. is formally described herein; this taxon differs from the other Middle E
ocene representatives of this genus by having a lower elongation index and
a larger proloculus. It is so far known only from the Late Bartonian of the
Colli Berici, and represents one of the smallest alveolinids following the
peak diversity of the Lutetian, Both species occur in shallow water calcar
enites, and are the only representatives of the Alveolinidae in Upper Barto
nian carbonate units of the Colli Berici.