The Alveolinoidea (‘alveolinoids’ herein) is a superfamily of larger benthic foraminifera (LBF) of the order Miliolida (= with porcelaneous test wall) that are common in the mid-Cretaceous shallow-water carbonate successions of Neotethys. They are encountered in suitable rocks in a broad belt centred around the Mediterranean region and the Arabian Plate but some taxa are found in the central American region. To improve their stratigraphic utility, the identities and distribution of 32 species are critically reviewed based on published records, these taxa having at least possible occurrences in Cenomanian strata. It is shown that misidentifications have overextended the ranges of some taxa, although there are indeed species that have long ranges. Nonetheless, some taxa have short ranges within the Cenomanian that mark them out as potential species to be used, alongside species from other LBF groups, in the development of a biozonation/bioevent scheme for Cenomanian LBF. Alveolinoids are amongst the most morphologically complex mid-Cretaceous LBF, and, as with modern members of the group, mostly lived in the shallow waters of inner carbonate platforms developed in tropical belts. This paleoenvironmental restriction means that their local stratigraphic ranges could often be incomplete compared to the total composite range. Speciations and extinctions within the group seem closely linked to paleoceanographic events including sea-level change, hypertermals and anoxia. As with almost all mid-Cretaceous LBF, work on the taxonomy/identity of alveolinoids is an ongoing task requiring access to pristine material, including types
Calcareous red algae are organisms of great relevance in paleontological studies as they were important producers of calcium carbonate throughout geological time. This is also true for the Albian – Cenomanian time-interval, when shallow-water carbonate factories experienced a general decline in the northern Neo-Tethyan areas. In this paper, red algae taxa belonging to the uppermost Albian - lower Cenomanian carbonate succession of the Enisala Member (Iancila Formation, Babadag Basin) were documented and described, along with their associated microfacies. Based on the identified fossil taxa and the microfacies analyses, interpretations of the depositional environments have been made, suggesting an open-marine platform interior environment with normal salinity levels and reduced luminosity. The age of the carbonate succession is considered to be within the latest Albian - early Cenomanian interval, based on fossil evidence from the studied samples and research done by previous authors.
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 Ardèche (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.
Persiconus sarvaki Yazdi-Moghadam & Schlagintweit represents one of the latest (perhaps the latest) orbitolinids that became extinct before the Cenomanian-Turonian boundary faunal turnover. P. sarvaki has an apparently endemic distribution with a restriction to middle-late Cenomanian carbonate platforms of the former Arabian Plate margin. It is herein described from a section of the Sarvak Formation located in the Izeh Zone of SW Iran where it occurs in inner platform foraminiferal wackestones assigned to the early late Cenomanian. Details on the microfacies and the biostratigraphy of the section that includes the Cenomanian-Turonian boundary are provided. The new observations on P. sarvaki highlight the presence of two different types of embryos (thick-walled, simple and thin epidermis with partitions, complex). The same phenomenon is already known from the Eocene Cushmania americana (Cushman). This aspect is discussed in more detail in view of the current classification of the Orbitolinidae; respectively its subfamilies. In addition, the previously unknown microspheric form of P. sarvaki is recorded, as well as occasional test infestation by the foraminifer Tauchella endolithica Cherchi & Schroeder.
The Loftusiida (“loftusiids” herein) is an order of “larger” benthic foraminifera (LBF) that are common in the Cretaceous neritic carbonate successions of Neotethys. They are encountered in suitable rocks in a broad belt centred around the Mediterranean region and the Arabian Plate but some taxa are found in Central America and the Himalayas. To improve their stratigraphic utility, the identities and distribution of 25 species (excluding those from the Suborder Orbitolinina) are critically reviewed based on published records, these taxa having at least possible occurrences in Cenomanian strata. It is shown that misidentifications have mistakenly overextended the ranges of some taxa, although there are indeed species that have long ranges. This suggests that some loftusiids formed part of a group of environmentally tolerant LBF that were able to recover from palaeoceanographic events such as widespread anoxia or eustatic sea-level change. Some other taxa have short ranges within the Cenomanian that mark them out as potential species to be used, alongside species from other LBF groups, in the development of a biozonation/bioevent scheme for Cenomanian LBF. As with almost all mid-Cretaceous LBF, work on taxonomy/identity of loftusiids is an ongoing task requiring access to pristine material, including topotypes.
