MILIOLIDAE - Acta Palaeontologica Polonica

MILIOLIDAE FROM MIOCENE OF POLAND 19
with Hanzawaia crassiseptata of the coastal zone) disappear abruptly at
a depth of 494.90 m, being immediately replaced first by single specimens
then by masses of Cycloforina stomata, C. predcarpatica and otoliths and
a few redeposited Tortonian specimens, whereas Anomalinoides dividens
does not appear in large numbers below 442 m. The bottom Sarmatian
layers, underlying the layer in which this typical species is present, are
about 57 m thick. In bore-hole Mielec-6 the rich Upper Tortonian
assemblage with agglutinating foraminifers disappears suddenly at a depth
of 829.2 m and barren layers with only few redeposited Tortonian specimens
occur between 829.20 and 816.0 m, whereas Cycloforina stomata and
otoliths appear in large numbers over 816 m and Anomalinoides dividens,
Cycloforina predcarpatica and Varidentella rosea, typical of the Sarmatian,
over 801 m.
As mentioned above, the bottom layers of the zone with Anomalinoides
dividens are for the most part poor in microfauna and contain the new
species Cycloforina stomata, which next persists into the higher layers
of this zone, but no longer as abundant. The higher layers of the zone
with Anomalinoides dividens are characterized by the appearance of
further new miliolid species: Articulina sarmatica, A. problema, A. multibullata,
A. tamanica, Cycloforina cristata, C. fluviata, C. gracilissima,
C. predcarpatica, C. toreuma, Varidentella latelacunata, V. pseudocostata,
V. rosea and V. rotunda. Except for Cycloforina cristata, C. fluviata and
C. gracilissima, they occur mostly in large numbers. Only few Tortonian
forms, like Affinetrina cubanica, Sinuloculina consobrina, S. nitens and
Sigmoilinita tenuis, are observed, in addition to which there are sporadic,
undoubtedly redeposited, single specimens of different Tortonian species
(Luczkowska, 1964 and 1967), which may form even a high percentage of
the whole assemblage. The Sarmatian sands from Dwikozy near Sandomierz
are a typical example of the occurrence of an assemblage of Sarmatian
Miliolidae mixed with redeposited Tortonian species.
Zone with Cycloforina karreri ovata. - This zone contains a number
of species from the lower layers, i.e., Articulina problema, A. sarmatica,
Cycloforina fluviata, C. gracilissima, C. predcarpatica, C. stomata, Affinetrina
cubanica, Sinuloculina consobrina, S. nitens, Varidentella latelacunata,
V. pseudocostata, V. rosea, V. rotunda and Sigmoilinita tenuis. The
new species that appear here in large numbers for the first time are
Cycloforina karreri ovata, Affinetrina voloshinovae timenda and Articularia
karreriella, occasional specimens of this last species being present
as deep as the zone with Anomalinoides dividens. In general, this zone
comprises a poor miliolid assemblage in so far as its specific differentiation
is concerned. It often lacks any microfauna at all.
Zone with Varidentella sarmatica. - This is the highest Sarmatian
zone with numerous miliolids in Poland. These are, above all, specimens
of the typical species Varidentella sarmatica, occurring in masses beside
2'