ACTA PALAEONTOLOGICA ROMANIAE
Acta Palaeontologica Romaniae, Vol. 21 (2) 2025 - Online Articles
PRINT ISSN 1842-371x
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Abstract. Iraqia simplex Henson, the type-species of this orbitolinid genus, is classified among the Dictyoconinae Schubert that is principally defined by a simple megalospheric embryo. However, neither the original nor any later description of the taxon contained any specifications (or illustration) of this taxonomically important feature except that it should be situated eccentrically at the beginning of an early spiral stage. Abundant material from the early Aptian Taft Formation of Central Iran, that is in perfect conformity with Henson's Iraqi type-material, shows the presence of a simple embryo positioned centrically at the apex of the generally high-conical tests. Apart from other differences in the internal test structure, this feature therefore appears to represent a further distinguishing criterion to the allied genus Orbitolinopsis Henson. The available material also provides a relatively good overview of the so far unknown embryo's biometric variability. Among the Dictyoconinae, a centric embryo can be considered as the exception rather than the rule.
FELIX SCHLAGINTWEIT, KOOROSH RASHIDI & REZA HANIFZADEH
STĂNILĂ IAMANDEI, EUGENIA IAMANDEI, DAN VALENTIN PALCU, IZABELA MARI & ALEXANDRU GABRIEL CĂLIN
Abstract. This study analyzes petrified wood samples collected from the Bulgarian Black Sea shore near the Byala locality. These specimens originate from the Galata Formation and date to the Chokrakian age (mid-Miocene). The three well-preserved specimens were identified as Cupressinoxylon sp. (cf. Thujoxylon sp.). In contrast, one poorly preserved specimen suggested a dicot structure and was recognized as Populoxylon sp. (cf. Populus tremula L.). The geological characteristics of the Galata Formation in this region are also discussed.
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FELIX SCHLAGINTWEIT
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Abstract. Pseudolituonella mariae Gendrot from the Santonian of southern France represents the only post-Cenomanian Upper Cretaceous species of the genus. The test morphology, inner and wall structure however are not in conformity with the characteristic features of Pseudolituonella Marie. P. mariae is taxonomically revised and transferred to the genus Gerochella Neagu thereby becoming the second species of the genus besides the lowermost Cretaceous Romanian type-species G. cylindrica. Other specimens of Gerochella described in open nomenclature from the late Maastrichtian of SW Iran show that the genus was widely distributed in Cretaceous shallow-water carbonates.
FELIX SCHLAGINTWEIT
Abstract. Moncharmontia De Castro (type-species M. apenninica) and Fleuryana De Castro et al. (type-species F. adriatica) represent two exclusively Upper Cretaceous genera of relatively small-sized benthic foraminifera with similar morphology and wall structure but distinguished primarily by the type of the aperture/foramina (multiple cribrate versus a single, central, arched slit piercing the septum). Solakiana gen. nov. (type-species Fleuryana gediki Solak et al.) differs from both taxa by its type of aperture, represented by a basal slit bordered at the base by the external wall of the previous whorl. Apertural/foraminal lips or septal plates are present in all three genera. The canaliculate wall-structure, well preserved in Moncharmontia and Fleuryana but poorly preserved in Solakiana, refer them tentatively to the family Charentiidae Loeblich & Tappan. The three genera are widely reported from neritic carbonates spanning the Cenomanian-Maastrichtian interval, each with different stratigraphic ranges. The group became extinct at the K-Pg boundary.
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IOAN I. BUCUR
Abstract. The genera Scythiolina and Histerolina described from the lowermost Cretaceous of Dobrogea (Romania) have very similar morphological and structural characteristics. The extremely rich population from which the species of the two genera were described presents a morphological continuum of conical, ellipto-conical, to slightly flabelliform forms. The other structural characteristics (e.g., presence of beams and sporadic rafters in the late ontogenetic stage) are practically identical. This leads me to infer that we are dealing with a single genus, Scythiolina having priority. In addition, detailed observations in thin sections of the original material have shown that the test wall has a microgranular structure and not finely canaliculate (
,
pseudokeriothecal
¢
) as specified in the original description. As such, an emended diagnosis for the genus Scythiolina is presented, and for the type species, Scythiolina flabelii.
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JEAN-PIERRE MASSE, MÜKERREM FENERCI-MASSE, JEAN-PIERRE PLATEL, CAMILLE FRAU & PHILIPPE LÉONIDE
Abstract. Two new species of the genus Horiopleura (Family Polyconitidae) are described from the Lower Cretaceous deposits of the Mediterranean Tethys margins. Horiopleura arabica comes from the lower Aptian Qishn Formation of southern Oman and Horiopleura helviorum, which occurs in the upper Barremian, Urgonian, Rustrel fauna but was primarily recorded in the lower Aptian deposits of Ardeche (SE France). In Horiopleura arabica the left valve projects dorsally off the commissural plane and the anterior myophore is a small crest, the right valve posterior myophore is a ledge; radial bands are weak but present. Horiopleura helviorum, the smallest species of the genus is characterized by a parietal lamellar anterior myophore on right valve. The two new species, are small and possess a domal left valve. They have a significant biostratigraphic and palaeobiogeographic potential. The new species illustrate a particular mode of arrangement of the anterior myophore on the right valve of Horiopleura, leading to a distinctive species grouping during the late Barremian-early Aptian. Our discoveries document a remarkable contemporaneous radiation of the Polyconitidae.
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