Palynological and paleobotanical investigation of bonebeds and other strata of the
Csehbánya
Formation from the vertebrate locality at Iharkút (Bakony Mts, Hungary) reveals well-preserved
Santonian palynological assemblages dominated by the Normapolles group, with a minor
component
consisting of other angiosperm pollen, some gymnosperm pollen, and spores. Eleven
species of
Normapolles-type pollen grains belonging to seven genera and fruit remains of a new
taxon,
Sphaeracostata barbackae gen. et sp. nov., are described. The new species is very
abundant in the material,
represented by ca. 1000 specimens. The genus Caryanthus Friis and an unnamed form
previously
reported from Hat¸eg by Lindfors et al. (2010) are also present.
Plants producing Normapolles-type pollen grains diversified during the Late Cretaceous,
with a
bloom in the Santonian. The palynostratigraphy of the Upper Cretaceous terrestrial
sediments in the
studied region is based on Normapolles-related species. The studied assemblage is
assigned to the
Oculopollis zaklinskaiae-Tetracolporopollenites (Brecolpites) globosus Zone (or Zone
C) indicating a late
Santonian age. Comparison of the Iharkút palynoflora with other known Upper Cretaceous
palynofloras of Central Europe shows diachronous occurrence of Normapolles taxa at
different
geographic localities and warrants further investigation.
The ecological requirements of the amphibian fauna reflect azonal conditions controlled
by the
availability of water, which is in agreement with the inferred ecological conditions
based on the
paleobotanical investigations. The fauna is of entirely non-marine character, further
supported by
isotope studies, in line with our data showing that the palynological samples contain
no marine forms.
