taxonID	type	description	language	source
061DF25FFFED432A680BADD9601C8836.taxon	description	1837 Orbitolites plana n. sp. – d’Archiac, p. 178. Cenomanian, France. Non 1890 Orbitolina concava - Martin, p. 211 - 219, pl. XXIV, fig. 1 - 13, pl. XXV, fig. 14 - 20 (= Palorbitolina lenticularis fide Schlagintweit & Simmons, 2023) 1960 a Orbitolina concava – Douglass, p. 32 - 34; pl. 2, fig. 1 - 12; pl. 3, fig. 1 - 9. Early Cenomanian, France. 1960 b Orbitolina concava - Douglass, pl. 2, fig. 6 - 7; pl. 4, fig. 12 - 13. Early Cenomanian, France. 1962 Orbitolina (Orbitolina) concava concava – Schroeder, p. 185 - 189, pl. 20, fig. 3 - 6, 8 - 10; pl. 21, fig. 6. Early Cenomanian, France. 1963 Orbitolina lenticularis (Blumenbach) – Hofker jr., text fig. 24; pl. 17, fig. 15 - 18; pl. 18, fig. 1 - 9. Early Cenomanian, France. Non 1964 Orbitolina (O.) concava concava – Schroeder, p. 688 - 690; text-fig. 3 a-d (= Orbitolina duranddelgai fide Schroeder in Schroeder & Neumann, 1985). Non 1969 – Orbitolina concava – Sampò, pl. 37, fig. 8 (= Palorbitolina lenticularis), pl. 39, fig. 10, 22 (= Mesorbitolina birmanica). 1970 Orbitolina concava – Chernov, p. 30 - 31, pl. 2, figs. 1 - 9. Early Cenomanian, Ukrainian Carpathians. Non 1972 Orbitolina (Orbitolina) concava concava – Ramirez del Pozo, p. 36, pl. 4, fig. 8 - 9 (= Mesorbitolina sp.) Non 1976 Orbitolina concava – Ho et al., p. 20, pl. 3, fig. 5 - 11. (= Palorbitolina ultima or Palorbitolinoides fide Rao et al., 2017). 1979 Orbitolina (Orbitolina) concava – Decrouez & Kunzle, pl. 1, fig. 1, 4; pl. 2, fig. 1 - 3 – Early Cenomanian, France. Non 1982 Orbitolina (Orbitolina) concava – Zhang, p. 75, pl. 12, fig. 8 - 9. Probably Palorbitolinoides sp. 1984 Orbitolina (Orbitolina) concava – Bilotte, p. 363 - 364, pl. 3, fig. 12 - 14. Middle Cenomanian, French Pyrenees. 1985 Orbitolina (Orbitolina) concava - Schroeder in Schroeder & Neumann, p. 62 - 66, pl. 29, fig. 1 - 8 Early Cenomanian, France. 1992 Orbitolina concava – Simmons & Williams, pl. 2, fig. 2. Early Cenomanian, France. Non 1992 Orbitolina concava – Kalantari, pl. 78, text-fig. 158 (= Mesorbitolina sp.) Diagnostic features: An Orbitolina with a relatively large embryonic apparatus (min 0.67 mm, max 1.21 mm, mean 0.85 mm) and an irregularly elliptical proloculus (min 0.17 mm, max 0.42 mm, mean 0.27 mm). Supra-embryonic zone divided by numerous vertical partitions of different lengths (orders). Sub-embryonic zone thin, a layer of numerous, irregular chambers. Radial zone chamber passages with an irregular rectangular-oval outline, with septulae alternating between chambers.	en	Bidgood, Michael, Schlagintweit, Felix, Simmons, Michael (2024): The Genus Orbitolina D’Orbigny, 1850 (Larger Benthic Foraminifera) And Its Constituent Species: Notes On Identity And Stratigraphic Ranges. Acta Palaeontologica Romaniae 20 (2): 33-59, DOI: 10.35463/j.apr.2024.02.05, URL: https://doi.org/10.35463/j.apr.2024.02.05
061DF25FFFED432A680BADD9601C8836.taxon	discussion	Remarks: Orbitolina concava (= Orbulites concava Lamarck, 1816) is the type species of Orbitolina (Schroeder & Simmons, 1988, 1989). First described over 200 years ago, it has had a complex history of usage. In the 19 th century and the first half of the 20 th century, as much attention was paid to the external morphology as to the internal morphology of the orbitolinids, leading to the use of species names that would not be deemed appropriate today, as taxonomic classification is now based on internal features almost exclusively (Henson, 1948; Douglass, 1960 a, 1960 b; Schroeder, 1962, 1963, 1975) (see Appendix). Consequently, taxa such as O. concava have many potential synonyms (Schroeder, 1962). An understanding of the stratigraphic range of O. concava is hampered by how the species name is being used – in a strict sense as used herein (sensu Schroeder, 1962); in a loose sense possibly including related Orbitolina (sensu lato) species, most of which were originally defined as varieties or subspecies of O. concava; or in the (incorrect) widest possible sense including a range of Orbitolininae. Some records, especially from the Aptian, Albian, and late Cenomanian of the Middle East, are clear misidentifications, unproven, or relate to outdated concepts of the species (see examples in Schlagintweit & Simmons, 2022 and also Bozorgnia & Banafti, 1964; Sampò, 1969; Kalantari, 1976, 1992; Rabu, 1993). Use of outdated species concepts also applies to records from Borneo (Schlagintweit & Simmons, 2023). Resolution of such taxonomic uncertainty requires detailed assessment of records that is beyond the scope of this study, although we have attempted to verify the most important range defining records. Orbitolina birmanica Sahni 1937 emend. Sahni & Sastri 1957 was tentatively considered a synonym of O. concava by Schroeder (1962) but has subsequently been shown to be a species of Mesorbitolina (Zhang, 1994; Schlagintweit & Wilmsen, 2014; Schlagintweit, 2024). Ho et al. (1976), Yang et al. (1982), and Zhang (1982) reported O. concava as occurring in the Cenomanian of Tibet, but the material is considered to be of the Palorbitolina ultima - Palorbitolinoides hedini lineage by Rao et al. (2017) and thus pre-Cenomanian (Schroeder et al., 2010). Measurements made by us on the embryonic apparatuses of scaled illustrations of topotypes of O. concava or from data from Douglass (1960 a), Schroeder (1962), Hofker (1963), Decrouez & Kundle (1979), Schroeder & Neumann (1985) and Simmons & Williams (1992) yielded the range of values shown in the diagnosis. It was noticed that Schroeder’s measurements in 1962 were close to those of Hofker’s (1963). However, later measurements by Schroeder (in Schroeder & Neumann, 1985) appeared to be 20 - 25 % larger and, in some respects, closer to those of Douglass (1960 a). This (apparent) discrepancy may be connected with issues surrounding image scaling during publication and subsequent re-measurement as discussed above. It could also reflect a genuine wide range of values. Regardless of this and considering the mean values, O. concava is still generally characterised as the species of Orbitolina with the largest embryonic apparatus diameter. Stratigraphic range: Early – middle Cenomanian (common records in the early Cenomanian, scarce records in the middle Cenomanian). First described from early Cenomanian sediments in Ballon, France (Lamarck, 1816), Schroeder in Schroeder & Neumann (1985) regarded the range of O. concava as being restricted to the entirety of the early Cenomanian (see range chart therein - a comment (p. 65) that it is “ Cénomanien supérieur ” is a lapsus calami). They reported no records outside of the early Cenomanian (with ammonite support) of France. This was followed by Simmons & Bidgood (2023). Its inception is considered as a useful proxy in carbonate platform settings for the base of the Cenomanian (Gale et al., 1996; Tröger & Kennedy, 1996; Velić, 2007; Simmons & Bidgood, 2023). Nonetheless, there is evidence that O. concava can be found in middle Cenomanian strata. Bilotte (1984) illustrated reasonable O. concava from the middle Cenomanian of the Pyrenees, an observation also made by Caus et al. (2009) without illustration. Co-occurrence with Praealveolina cretacea (d’Archiac, 1837) or Praealveolina debilis Reichel, 1936 supports this assertion. El Sheikh & Hewaidy (1998) reported O. concava from the middle Cenomanian of Egypt (with Praealveolina tenuis Reichel, 1933), but the illustration is inconclusive. In the Adriatic Platform, Velić (2007), considers the species as occurring in the early and middle Cenomanian (see illustration in Velić, 1988). It is interesting to note that Schroeder (1975) placed the range of “ O. concava concava ” in the overlap between a twofold subdivision of the Cenomanian, thereby implying extension into the middle Cenomanian, a view he presumably changed in the ten years subsequent. Although sometimes reported (but seldom illustrated) from late Albian strata (e. g., Decrouez & Moullade, 1974; Bilotte et al., 1978; Moullade et al., 1985; Görög, 1993; Ahmadi et al., 2008; Afghah et al., 2020), it may be that these records are actually of ancestral Orbitolina species or of O. concava sensu lato (herein Orbitolina spp.) (e. g., Rey et al., 1977 – see Berthou & Schroeder, 1978), or that the late Albian age is unproven, so are herein discounted. In the literature on the Middle East, there are some misleading statements about the range of O. concava (Schlagintweit & Simmons, 2022). For example, Haftlang et al. (2020) misquote the literature suggesting that Schroeder et al. (2010) indicated that O. concava is an Albian species (and thereby justifying a possible Albian age for rocks in which they supposedly find this species – the illustrations are indeterminate). There is no such statement that O. concava is an Albian species in Schroeder et al. (2010). Other records of O. concava from the Albian of the Iranian Zagros (Kalantari, 1976; Keshavarzi et al., 2020, 2021) are indeterminate and must be doubted. An illustrated record from the potentially late Albian Maududd Formation of southern Iraq (Manhi & Alsultani, 2021) is indeterminate. Palaeogeographic distribution: Excepting an interesting record from eastern Europe (Chernov, 1970), the majority of viable records of this species are from western Europe. Although widely reported from the Arabian Plate (including the Zagros), most records cannot be confirmed as this species due to the illustrated specimens being unsuitable for definitive identification (e. g. Mohammed, 1996; Ameen & Gharib, 2014; Farsi et al., 2022). Amongst the possible records are those of Schlagintweit & Yazdi-Moghadam (2020, 2021, 2023) and Yazdi-Moghadam & Schlagintweit (2020, 2021, 2022), although as previously noted, they use the term “ Orbitolina gr. concava ” to designate a degree of uncertainty, given the need to access both suitable axial and tangential sections to observe all the relevant features to confirm identification. Thus, they are herein included within Orbitolina spp. (see below). The records of Weidich & Al Harithi (1990) from the Albian / Cenomanian transition of Jordan, seem to conform to O. hensoni. Simmons et al. (2000) noted that the species appears to be absent from the F. R. S. Henson and Associates Collection in the Natural History Museum, London, which is based on Middle East material. Henson (1948: fig. 46) provided a detailed drawing of an embryo of ‘ O. concava vars. ’ Displaying a broad peri-embryonic zone, this specimen can be referred to Palorbitolinoides Cherchi & Schroeder (compare Schlagintweit et al., 2022: fig. 5 n).	en	Bidgood, Michael, Schlagintweit, Felix, Simmons, Michael (2024): The Genus Orbitolina D’Orbigny, 1850 (Larger Benthic Foraminifera) And Its Constituent Species: Notes On Identity And Stratigraphic Ranges. Acta Palaeontologica Romaniae 20 (2): 33-59, DOI: 10.35463/j.apr.2024.02.05, URL: https://doi.org/10.35463/j.apr.2024.02.05
061DF25FFFEF432B6829AEC366838F31.taxon	description	? 1962 Orbitolina (Orbitolina) concava qatarica – Schroeder, p. 191 - 193, pl. 20, fig. 11; pl. 21, fig. 2. Early Cenomanian, Spain. 1985 Orbitolina (Orbitolina) sefini - Schroeder in Schroeder & Neumann, pl. 30, fig. 1 - 3 “ Cenomanian ”, Iraq. Could be late Albian. Non 1985 Orbitolina (Orbitolina) sefini – Schroeder in Schroeder & Neumann, p. 66 - 68, pl. 30, fig. 4 - 8. Probably Orbitolina hensoni. Non 1992 Orbitolina sefini – Simmons & Williams, pl. 1, fig. 3 - 5. Probably O. hensoni.? 1999 Orbitolina sefini Henson – Cherchi & Schroeder, p. 20, pl. 2, figs. 1 - 8, pl. 3, figs. 1 - 3. Early Cenomanian, Spain. 2000 Orbitolina sefini – Simmons et al., p. 423, pl. 1, fig. 8; pl. 2, figs. 3 - 5; pl. 4, fig. 10. “ Cenomanian ”, Iraq. Could be late Albian. Non 2004 Orbitolina sefini – Schulze et al., text-fig. 10 b. Indeterminate orbitolinid, but not Orbitolina sp. Non 2013 Orbitolina sefini – Ghanem & Kuss, pl. 14, fig 5 - 6 (= Conicorbitolina sp.), 7 (= Cuneolina or Dicyclina sp.), 9 (= indeterminate orbitolinid) Diagnostic features: An Orbitolina with a proloculus of max diameter c. 0.25 mm and an embryonic apparatus diameter of 0.45 – 0.60 mm. The supra-embryonic zone is highly subdivided. Sub-embryonic zone thin. Radial zone chamber passages are initially triangular in section, becoming rectangular in later chambers. This variation is also observed in different generations (triangular in macrospheric, elliptical / subrectangular in microspheric).	en	Bidgood, Michael, Schlagintweit, Felix, Simmons, Michael (2024): The Genus Orbitolina D’Orbigny, 1850 (Larger Benthic Foraminifera) And Its Constituent Species: Notes On Identity And Stratigraphic Ranges. Acta Palaeontologica Romaniae 20 (2): 33-59, DOI: 10.35463/j.apr.2024.02.05, URL: https://doi.org/10.35463/j.apr.2024.02.05
061DF25FFFEF432B6829AEC366838F31.taxon	discussion	Remarks: First defined as a variety (= subspecies) of O. concava by Henson (1948) based on material from Sefin Dagh in NE Iraq. As noted by a number of workers (e. g., Schroeder in Schroeder & Neumann, 1985; Simmons et al., 2000) the original description and illustration of the species included a variety of taxa recognised using modern concepts of Orbitolininae, further amplified by assessment of material in the F. R. S. Henson and Associates Collection in the Natural History Museum, London. Nonetheless, Schroeder in Schroeder & Neumann (1985), Schroeder et al. (1986) and Cherchi & Schroeder (1999) in a revaluation of the species considered that the type material included an Orbitolina distinct from O. concava by virtue of a smaller embryonic apparatus and exclusively triangular chamber passages (in megalospheric forms). The exclusively triangular nature of the chamber passages was refuted by Simmons et al. (2000) who considered that the chamber passages are initially triangular but become rectangular in later adult chamber layers. This is still distinct from O. concava and O. qatarica that have exclusively rectangular chamber passages. Simmons et al. (2000) introduced Orbitolina hensoni for material that has only triangular chamber passages based on “ Orbitolina cf. concava ” sensu Henson (1948). Despite the work of Schroeder in Schroeder & Neumann (1985), Schroeder et al., (1986), Cherchi & Schroeder (1999) and Simmons et al. (2000) identification of O. sefini remains challenging, not least because the syntypes of Henson (1948) only include poor or somewhat oblique sections through the embryonic apparatus as illustrated by Simmons et al. (2000) (Henson, 1948 illustrated none). Schroeder in Schroeder & Neumann (1985) and Schroeder et al. (1986) illustrated axial sections of the embryonic apparatus based on material from western Europe thought to be O. sefini, but now might be better attributable to O. hensoni following Simmons et al. (2000). Cherchi & Schroeder (1999) made an important observation in that in material considered by them to be O. sefini from the early Cenomanian of Spain, chamber passage shape varies between macrospheric and microspheric generations. In macrospheric forms they considered chamber passage shape to be exclusively triangular, but in microspheric forms to be elliptical to sub-rectangular (illustrations show some triangular passages as well). This complicates species determination, as care needs to be taken to assess the generation of specimens being observed. For example, in the type material of O. sefini from Iraq, it is not possible to determine the generation of specimens showing tangential sections and chamber passage shape. This is also true for O. hensoni, leading to the possibility that O. sefini and O. hensoni (sensu Simmons et al., 2000) represent different generations of the same taxon. This can only be resolved by study of more topotype material. Herein, we consider that the material of Cherchi & Schroeder (1999) is probably O. sefini but needs to be proven by comparison with additional type material. Stratigraphic range: Very latest Albian – earliest Cenomanian (uncertain). Difficulties in the reliable identification of O. sefini challenge an assessment of its stratigraphic range. Henson (1948) considered the species to be Cenomanian, but this is partly due to the broad concept of the taxa he employed that might include other Cenomanian Orbitolininae (e. g., species of Conicorbitolina). Furthermore, the Cenomanian age of the type locality at Sefin Dagh is unproven. It could certainly be late Albian. Schroeder in Schroeder & Neumann (1985) considered the species to be latest Albian – earliest Cenomanian and Schroeder et al (1986) recorded it from the late Albian of SW England supported by ammonite records. However, these records are now better assigned to O. hensoni. Lopez-Horgue et al. (2009) consider that the range may extended to low in the late Albian of Spain (variscum Zone, binum subzone = approximately mid- pricei zone fig. 3 herein) because of ammonite co-occurrences, but confirmation of the identity of O. sefini is uncertain (= Orbitolina spp. herein). Specimens of “ Orbitolina (Orbitolina) concava qatarica ” illustrated by Schroeder (1962) from the early Cenomanian of Spain may be this species, given the embryonic apparatus dimensions (total diameter 0.68 mm and proloculus diameter 0.26 mm) and chamber passages that appear to grade from triangular to rectangular. The species has been extensively reported from the Middle East, although many records are without illustration, or only supported by illustrations that are effectively inadequate to determine species. Simmons & Hart (1987) illustrated an uncertain specimen from the lower Natih Formation of Oman (latest Albian – earliest Cenomanian according to Bromhead et al., 2022). This is equivalent to the Mauddud Formation recognised in many parts of Arabia, and from which O. sefini is frequently reported, although seldom with supporting definitive illustration (see for example, Mohammed, 1996; Noori et al., 2016; Youssef et al., 2019; Navidtalab et al., 2020; Manhi & Alsultani, 2021; Shakir & Mousa, 2023 – all unconfirmed). Al-Mamory & Al-Dulaimi (2020) Ameen & Gharib (2014) report the species from the Qamchuqa Formation of northern Iraq, but the illustrations are indeterminate. The species has been reported from the early Cenomanian of Israel (Frank et al., 2010), whilst illustrations by Hamaoui (1965) from Israel of “ Orbitolina cf. O. concava sefini ” are probably of Conicorbitolina. Records from the middle – base late Cenomanian of NW Syria (Ghanem & Kuss, 2013) are also most likely of Conicorbitolina and can be discounted from an assessment of stratigraphic range. A record from the late Albian – early Cenomanian Naur Formation of Jordan (Schulze et al., 2004) is not of Orbitolina as illustrated. Xu et al. (2023) illustrate the species (as “ cf. ”) from the late Albian upper Khazdumi Formation of the Iranian Zagros, but the specimen is best considered as Orbitolina spp. as defined herein. Likewise, Luger (2018) confidently reports the species from the late Albian – early Cenomanian of Somalia, but the illustrations are probably better assigned to Orbitolina spp. Palaeogeographic distribution: As with assessment of stratigraphic range, difficulties in the reliable identification of O. sefini challenge an assessment of its palaeogeographic distribution. Iraq remains the only area where its presence – poor definition notwithstanding – has been confirmed (southern Neotethys), with other possible occurrences in Oman and Spain.	en	Bidgood, Michael, Schlagintweit, Felix, Simmons, Michael (2024): The Genus Orbitolina D’Orbigny, 1850 (Larger Benthic Foraminifera) And Its Constituent Species: Notes On Identity And Stratigraphic Ranges. Acta Palaeontologica Romaniae 20 (2): 33-59, DOI: 10.35463/j.apr.2024.02.05, URL: https://doi.org/10.35463/j.apr.2024.02.05
061DF25FFFEE43246AA7A9FF66358FB2.taxon	description	Non 1969 Orbitolina concava (Lamarck) qatarica Henson – Sampò, pl. 39, figs. 16 - 17, 19 - 21 (= Palorbitolinoides hedini Cherchi & Schroeder fide Schlagintweit et al., 2022). Non 1976 Orbitolina concava qatarica – Ho et al., p. 20, pl. 3, fig. 4, 1 - 16. (= Palorbitolina ultima or Palorbitolinoides fide Rao et al., 2017).? 1993 Orbitolina qatarica - Hewaidy & Al-Hitmi, p. 479, pl. 5, fig. 4 - 7. Late Albian, subsurface Qatar.? 1996 Orbitolina qatarica – Mohammed, p. 66 - 68, pl. 7, fig. 8 - 9; pl. 8, fig. 1 - 3. Late Albian, subsurface southern Iraq. 2000 Orbitolina qatarica – Simmons et al., p. 423 - 424, pl. 2, figs. 7 - 9. Most likely late Albian, subsurface Qatar (see text). 2018 Orbitolina qatarica – Luger, p. 75 - 77, pl. 8, fig. 11 - 14, pl. 9, fig. 1 - 5. Early Cenomanian, Somalia. Diagnostic features: An Orbitolina with a proloculus of max diameter c. 0.20 mm, and which is often convex upwards with a flat base. The embryonic apparatus diameter is 0.72 – 0.75 mm. The supra-embryonic zone is markedly conical, relatively thick and highly subdivided. The sub-embryonic zone is thin, convex and highly subdivided. Radial zone chamber passages are almost exclusively rectangular in section.	en	Bidgood, Michael, Schlagintweit, Felix, Simmons, Michael (2024): The Genus Orbitolina D’Orbigny, 1850 (Larger Benthic Foraminifera) And Its Constituent Species: Notes On Identity And Stratigraphic Ranges. Acta Palaeontologica Romaniae 20 (2): 33-59, DOI: 10.35463/j.apr.2024.02.05, URL: https://doi.org/10.35463/j.apr.2024.02.05
061DF25FFFEE43246AA7A9FF66358FB2.taxon	discussion	Remarks: Initially introduced as a variety of O. concava by Henson (1948), it was elevated to subspecies then species status by a number of workers (e. g., Schroeder, 1962, 1975; Simmons et al., 2000; Luger, 2018). In his review of O. concava and O. sefini, Schroeder in Schroeder & Neumann (1985) considered O. qatarica as morphologically intermediate between them. Simmons et al. (2000) considered it as a distinct species, that whilst having mostly rectangular chamber passages and a large embryonic apparatus (both typical of O. concava), the embryonic apparatus was sufficiently distinct in subconical form and highly divided supra-embryonic and sub-embryonic zones. Luger (2018) independently came to similar conclusions, and emphasised the relationship to O. sefini, as opposed to O. concava, noting that some specimens could only be considered “ O. sefini / qatarica ”. Nonetheless, he recorded viable specimens from the early Cenomanian of Somalia (including an invalid lectotype – not from original syntypes). Within the syntypes of Henson (1948) there is a specimen (pl. 5, fig. 11 therein) that has been regarded as aberrant (Simmons et al., 2000; Luger, 2018). In fact, this specimen conforms to Mesorbitolina aperta (Erman), highlighting the mixture of taxa that can occur in several syntypic series of Henson (1948) (Simmons et al., 2000). As with all species of Orbitolina, multiple, good quality axial and tangential sections are required to confirm identity, and as such, records of its stratigraphic range are hard to confirm. Misidentifications also occur, for example by Sampò (1969) from the Albian of the Iranian Zagros that include Palorbitolinoides hedini (fide Schlagintweit et al., 2022). Older records (e. g., Schroeder, 1962; Berthou & Schroeder, 1978) might be better incorporated in the modern concept of O. sefini or O. hensoni. Stratigraphic range: Latest Albian – early Cenomanian (confident but scarce), uncertain in middle Cenomanian. The type locality in the subsurface of Qatar was considered Cenomanian by Henson (1948), supported by the co-occurrence with Praealveolina tenuis. Although this is oft-cited, Le Blanc (2015) showed that the type material in fact comes from the Mauddud Formation (late Albian according to Bromhead et al., 2022) and that the P. tenuis records represent caving. See also effective topotypes illustrated by Hewaidy & Al-Hitmi (1993), although their identity is uncertain. It is also reported from the Mauddud of Qatar by El Beialy & Al-Hitmi (1994), but the illustrations cannot be identified. Hofker (1963) illustrated the embryonic apparatus of each of three specimens of what he termed “ Orbitolina lenticularis ” from the type locality (but not the type horizon?) of O. qatarica (pl. 17, fig. 11 - 13). Their identity is uncertain but seems unlikely to be Orbitolina sensu stricto. Owen & Nasr (1958) and van Bellen et al. (1959) reported (without illustration) the species from the Rumaila Formation of southern Iraq. If correct, this would imply an age as young as middle Cenomanian (Bromhead et al., 2022). Many other records from southern Iraq are from the late Albian Mauddud Formation (Noori et al, 2016; Ezzulddin & Ibrahim, 2022; Shakir & Mousa, 2023), although only those of Mohammed (1996) are potentially plausible, others indeterminate or being ascribable to Orbitolina spp. at best. This includes a record from the Mauddud in southern Iran (Farsi et al., 2022), although the authors regard this as proof of a middle Cenomanian age, counter to regional evidence. It was also recorded from the late Albian Qamchuqa Formation of N. Iraq (Ameen & Gharib, 2014), but the illustrations are uncertain. Records from the early Cenomanian of Spain (Ramirez del Pozo, 1972) and Tibet (Ho et al., 1976; Yang et al., 1982; BouDagher-Fadel et al., 2017; Xu et al., 2019, 2021) are either not illustrated or misidentified. The records of Ho et al. (1976) from Tibet are considered to be of the Palorbitolina ultima - Palorbitolinoides hedini lineage by Rao et al. (2017). In summary, the potential stratigraphic range is late Albian – early Cenomanian, possibly middle Cenomanian, although more work is needed to confirm this. Palaeogeographic distribution: In common with other Orbitolina species, confirmed records of O. qatarica remain few and so far, restricted to Qatar and Somalia (southern Neotethys). Other possible occurrences are reported from southern Iraq.	en	Bidgood, Michael, Schlagintweit, Felix, Simmons, Michael (2024): The Genus Orbitolina D’Orbigny, 1850 (Larger Benthic Foraminifera) And Its Constituent Species: Notes On Identity And Stratigraphic Ranges. Acta Palaeontologica Romaniae 20 (2): 33-59, DOI: 10.35463/j.apr.2024.02.05, URL: https://doi.org/10.35463/j.apr.2024.02.05
061DF25FFFE143256A8BAE7F61A78DA6.taxon	description	1963 Orbitolina lenticularis – Hofker jr., pl. 17, fig. 5; pl. 20, fig. 2, 4 - 6. Albian – Cenomanian transition, Spain. 1964 Orbitolina (O.) concava concava – Schroeder, p. 688 - 690, text-fig. 3 a-d. Albian – Cenomanian transition, Spain. 1965 Orbitolina conica – Saint-Marc, pl. 4, fig. 2; pl. 14, fig. 7. Early Cenomanian, France. T 1972 Orbitolina (Orbitolina) duranddelgai n. sp. – Schroeder, p. 114 - 116; text-fig. 2 - 3 Albian – Cenomanian transition, Spain. 1973 Orbitolina (O.) duranddelgai – Bilotte, pl. 1, fig. 1 - 4; pl. 4, fig. 9 Latest Albian, Pyrenees, France. 1973 Orbitolina (O.) duranddelgai – Schroeder, text-fig. 2 - 3 Albian – Cenomanian transition, Spain. 1976 Orbitolina (O.) duranddelga i – Peybernes, p. 394; pl. 31, fig. 3 - 4; pl. 32, fig. 18 - 19 Latest Albian, Spain 1976 Orbitolina (O.) duranddelgai – Cherchi & Schroeder, p. 1217; text-fig. 1 Latest Albian – early Cenomanian, Sardinia.? 1977 Orbitolina (O.) duranddelga i – Rey et al., p. 378; pl. 2, fig. 7 Latest Albian, Portugal. 1984 Orbitolina (Orbitolina) duranddelgai – Bilotte, p. 364, pl. 1, fig. 10 (figs. 5 - 9 uncertain). Latest Albian, Pyrenees. 1985 Orbitolina (O.) duranddelgai – Schroeder in Schroeder & Neumann, p. 68 - 70, pl., 31, fig. 1 - 9 late Albian, Spain. Non 1993 Orbitolina (Orbitolin a) duranddelgai – Bravo & Garcia, pl. 3 (1). Appears similar to O. qatarica, but best classified as Orbitolina spp. in the absence of definitive sections. Diagnostic features: An Orbitolina with a proloculus of diameter 0.25 – 0.30 mm and height 0.14 – 0.16 mm, and which is irregularly ellipsoidal or cup-shaped. The embryonic apparatus diameter is 0.50 – 0.70 mm (max 0.80 mm). The supra-embryonic zone is highly subdivided. The sub-embryonic zone is thin, and only weakly subdivided. Radial zone chamber passages are numerous and densely-spaced, oval to squarish.	en	Bidgood, Michael, Schlagintweit, Felix, Simmons, Michael (2024): The Genus Orbitolina D’Orbigny, 1850 (Larger Benthic Foraminifera) And Its Constituent Species: Notes On Identity And Stratigraphic Ranges. Acta Palaeontologica Romaniae 20 (2): 33-59, DOI: 10.35463/j.apr.2024.02.05, URL: https://doi.org/10.35463/j.apr.2024.02.05
061DF25FFFE143256A8BAE7F61A78DA6.taxon	discussion	Remarks: This species was introduced by Schroeder (1972) for an Orbitolina with numerous, small, oval – squarish radial chamber passages, more densely spaced than in Orbitolina concava and an embryonic apparatus 0.5 - 0.7 mm (0.8 mm max) in diameter. Stratigraphic range: Very latest Albian – earliest Cenomanian (confident and common). Based on the type material from Spain, the species was originally considered as Cenomanian, but corrected (for the type material) to latest Albian (dispar zone = approximately rostratum / perinflatum zones fig. 3 herein) by Schroeder in Schroeder & Neumann (1985). Nonetheless, it was (mistakenly) considered a useful early Cenomanian zonal fossil by Schroeder (1973, 1975). Following discussion of the age range by Bilotte et al. (1978) and Berthou & Schroeder (1978), O. duranddelgai was further described by Schroeder in Schroeder & Neumann (1985) with a suggested short range of latest Albian to earliest Cenomanian. The Cenomanian extension to the range was established from records with Praealveolina from France and Spain (Debuyser & Schroeder, 1972; Peybernes, 1976; Babinot et al., 1991; Caus et al., 1993, 2009; Calonge et al., 2003; Calonge-Garcia & Lopez- Carillo, 2003; Consorti et al., 2016). Nonetheless, Schroeder et al. (1993) noted its value as a marker for the latest Albian in eastern Spain (see also Bilotte et al., 1978; Moullade et al., 1985) and Bilotte (1984) illustrated material from the latest Albian of the French Pyrenees. Martin-Chivelet (1994) considered it an early Cenomanian marker in Spain, thereby emphasising the possibility of short local ranges. The need to observe both sections of the embryonic apparatus and the chamber passages led Castro et al. (2001) and Bachmann et al. (2003) to use the term “ Orbitolina sefini / duranddelgai ”, with Luger (2018) emphasising the difficulty of identifying Orbitolina sensu stricto species in the absence of multiple suitably oriented sections. Bachmann et al. (2003) considered “ Orbitolina sefini / duranddelgai ” to potentially range from the inflatum zone (= approximately cristatum - fallax zones fig. 3 herein) of the late Albian – middle early Cenomanian (restricted to the late Albian in northern Sinai) but provided no illustrations. Palaeogeographic distribution: The species may be endemic to the western Mediterranean (northern margin of Neotethys), with most viable records from Spain or the French Pyrenees. The only records from the Arabian Plate are those of Afghah & Fanati Rashidi (2007) from the (Albian) Kazhdumi Formation of the Iranian Zagros (not illustrated) and BouDagher-Fadel (2018) (identification and stratigraphic position uncertain, but not O. duranddelgai). Therefore, O. duranddelgai appears to be absent from the Arabian Plate, a view supported by Dr. Mohsen Yazdi-Moghadam (pers. comm., 2024).	en	Bidgood, Michael, Schlagintweit, Felix, Simmons, Michael (2024): The Genus Orbitolina D’Orbigny, 1850 (Larger Benthic Foraminifera) And Its Constituent Species: Notes On Identity And Stratigraphic Ranges. Acta Palaeontologica Romaniae 20 (2): 33-59, DOI: 10.35463/j.apr.2024.02.05, URL: https://doi.org/10.35463/j.apr.2024.02.05
061DF25FFFE043266A3FA86C63E0889A.taxon	description	? 1978 Orbitolina (Orbitolina) cf. concava qatarica – Berthou & Schroeder, p. 76, pl. 4, fig. 8 - 12. Early Cenomanian, Portugal.? 1985 Orbitolina (Orbitolina) sefini – Schroeder in Schroeder & Neumann, pl. 30, fig. 4 - 8. Late Albian, Spain. 1986 Orbitolina (Orbitolina) sefini – Schroeder et al., p. 383 - 385, text fig. 2 a-g. Late Albian, SW England. 1990 Orbitolina (Orbitolina) concava – Weidich & Al-Harithi, p. 605 - 606, pl. 5, figs. 1 - 10. Albian – Cenomanian transition, Jordan (age in part based on this occurrence). 1992 Orbitolina sefini – Simmons & Williams, pl. 1, figs. 3 - 5. Late Albian, south-west England. T 2000 Orbitolina hensoni n. sp. – Simmons et al., p. 423, pl. 2, fig. 1 - 2; pl. 4, fig. 9. Late Albian, subsurface Iraq. Diagnostic features: An Orbitolina with a proloculus of max diameter c. 0.25 mm. The proloculus is not well known in published illustrations but appears concave upwards. The embryonic apparatus diameter is c. 0.60 mm and generally has a flat base. The supra-embryonic zone is highly subdivided. The sub-embryonic zone is thin, and less strongly subdivided than the supra-embryonic zone. Radial zone chamber passages are distinctive and exclusively equilateral triangular in shape.	en	Bidgood, Michael, Schlagintweit, Felix, Simmons, Michael (2024): The Genus Orbitolina D’Orbigny, 1850 (Larger Benthic Foraminifera) And Its Constituent Species: Notes On Identity And Stratigraphic Ranges. Acta Palaeontologica Romaniae 20 (2): 33-59, DOI: 10.35463/j.apr.2024.02.05, URL: https://doi.org/10.35463/j.apr.2024.02.05
061DF25FFFE043266A3FA86C63E0889A.taxon	discussion	Remarks: Following their reappraisal of Orbitolina sefini, Orbitolina hensoni was introduced by Simmons et al. (2000) for Orbitolina with exclusively triangular chamber passages. An embryonic apparatus with a diameter of 0.6 mm and a flat-based, upwards concave proloculus is a supplementary defining feature, although the proloculus shape is poorly known. Specimens of “ O. (O.) sefini ” from the late Albian of Spain illustrated by Schroeder in Schroeder & Neumann (1985) that may be better referred to O. hensoni (note triangular chamber passages) have a cup-shaped or spherical proloculus. The embryonic apparatus is a little larger (diameter 0.7 - 0.8 mm; proloculus diameter 0.2 mm) than the type material of O. hensoni. Specimens of “ O. sefini ” from the late Albian of southwest England (Schroeder et al., 1986; Simmons & Williams, 1992) have clearly triangular chamber passages and an embryonic apparatus in the size range of O. hensoni, although its morphology is slightly different. See discussion of O. sefini for issues surrounding chamber passage shape that differ between macrospheric and microspheric generations (Cherchi & Schroeder, 1999). Conceptually, this might be a difference that mistakenly led Simmons et al. (2000) to separate O. hensoni from O. sefini but cannot be proved without a review of better topotype material. Stratigraphic range: Latest Albian (confident and common) – (uncertain)? earliest Cenomanian. With type material from the Naftah- 1 well in Iraq, the range was tentatively regarded as late Albian. The only other named record of the species is that of Farsi et al. (2022) who provided indeterminate illustrations from the (late Albian) Mauddud portion of the Sarvak Formation from the Iranian Zagros (Kuh-e-Genu). The species may have been recorded from the early Cenomanian of Portugal as “ Orbitolina (Orbitolina) cf. concava qatarica ” (Berthou & Schroeder, 1978). Specimens of “ Orbitolina (Orbitolina) concava ” illustrated by Weidich & Al-Harithi (1990) from the Albian / Cenomanian transition of Jordan fit well with the identity of O. hensoni in terms of embryonic apparatus size and chamber passage shape. Palaeogeographic distribution: Confirmed records (notwithstanding issues concerning identity) range from Jordan and Iraq to the UK with possible records also from Iran and the Iberian Peninsula. Consequently O. hensoni as interpreted herein appears to be the most widespread of the Orbitolina species.	en	Bidgood, Michael, Schlagintweit, Felix, Simmons, Michael (2024): The Genus Orbitolina D’Orbigny, 1850 (Larger Benthic Foraminifera) And Its Constituent Species: Notes On Identity And Stratigraphic Ranges. Acta Palaeontologica Romaniae 20 (2): 33-59, DOI: 10.35463/j.apr.2024.02.05, URL: https://doi.org/10.35463/j.apr.2024.02.05
061DF25FFFE3432669FDAF6066DD8F2E.taxon	description	T 1962 Orbitolina (Orbitolina) concava pauletensis – Schroeder, p. 189 - 191, pl. 20, fig. 1 - 2, 12. Early Cenomanian, France. 1964 Orbitolina (Orbitolina) concava pauletensis – Schroeder, p. 687, text-fig. 2. Early Cenomanian, France. Diagnostic Features: An Orbitolina with a proloculus of max diameter c. 0.28 mm. The embryonic apparatus diameter is c. 0.875 mm. The supra-embryonic zone is highly subdivided. The sub-embryonic zone is thin, and weakly subdivided. Radial zone chamber passages are triangular at first, becoming rectangular in older chambers.	en	Bidgood, Michael, Schlagintweit, Felix, Simmons, Michael (2024): The Genus Orbitolina D’Orbigny, 1850 (Larger Benthic Foraminifera) And Its Constituent Species: Notes On Identity And Stratigraphic Ranges. Acta Palaeontologica Romaniae 20 (2): 33-59, DOI: 10.35463/j.apr.2024.02.05, URL: https://doi.org/10.35463/j.apr.2024.02.05
061DF25FFFE3432669FDAF6066DD8F2E.taxon	discussion	Remarks: Introduced as a new subspecies of Orbitolina concava by Schroeder (1962) based on type material from supposedly basal Cenomanian sandstones at St Paulet in the Gard region of southern France. At the time, Schroeder (1962) distinguished two other subspecies of Orbitolina concava: Orbitolina concava concava and Orbitolina concava qatarica. Orbitolina concava pauletensis was differentiated on the basis of a thin (0.04 – 0.05 mm) and poorly subdivided subembryonic zone. The embryonic apparatus appears to be around 0.875 mm in diameter (second largest to O. concava), and the proloculus has a maximum diameter of 0.24 – 0.28 mm. The chamber passage shape is triangular becoming rectangular in adult chambers. Schroeder (1962) considered it the oldest member of a pauletensis – qatarica – concava lineage. However, after 1962, Schroeder almost never mentioned the species again (it is completely ignored in his 1975 and 1985 reviews for example and only very briefly mentioned and illustrated by Schroeder (1964 )). Stratigraphic range: Earliest Cenomanian (confident but scarce records). Neumann & Schroeder (1981) mention it with a late Albian – early Cenomanian range, but without explanation. In practice, the species needs to be redescribed on the basis of type and topotype material, and if valid, its range reassessed. Palaeogeographic distribution: In so much as the species is known, it appears to be endemic to the western Mediterranean (Western Neotethys).	en	Bidgood, Michael, Schlagintweit, Felix, Simmons, Michael (2024): The Genus Orbitolina D’Orbigny, 1850 (Larger Benthic Foraminifera) And Its Constituent Species: Notes On Identity And Stratigraphic Ranges. Acta Palaeontologica Romaniae 20 (2): 33-59, DOI: 10.35463/j.apr.2024.02.05, URL: https://doi.org/10.35463/j.apr.2024.02.05
061DF25FFFE243206A3AAF0F66F48E84.taxon	description	Age range summaries for the constituent species of Orbitolina including Orbitolina spp. are given in Figure 3. In this work we have used three broad categories to depict stratigraphic range confidence: Confident and Common - a wide, solid, green line on Figure 3 A relatively large number of (correctly) illustrated records (or if unillustrated, from a generally reliable source) with at least plausible age-control. Confident but Scarce – a narrow, solid, green line on Figure 3 At least one, but relatively fewer records but which fit the same criteria as above. Uncertain – a series of orange “? ” on Figure 3 Occurrences that lie outside of the “ confident ” ranges that are neither confirmed in terms of identity nor age-control but cannot be completely dismissed (e. g., an illustrated record with poor age-control or an unillustrated record from a generally reliable source with good age control). As can be readily understood, subjectivity plays a role here, and the boundaries between one category and another are inevitably gradational. Records which exist of named species occurring in rocks outside of these ranges, but which are based on very uncertain (i. e. dubious) identity and / or age control are not shown on Figure 3. Species of Orbitolina sensu stricto can be demonstrated to occur across an area extending from north-west Europe, the circum-Mediterranean, and to Somalia and the Arabian Plate. There may be some endemic patterns in this distribution as suggested by Luger (2018). For example, O. concava and O. duranddelgai are not convincingly found outside of the Northwest Europe - Mediterranean region. It is unclear if different lineages of Orbitolina independently arose from Mesorbitolina (?) ancestral stock in the Mediterranean and Arabian Plate, or if taxa arose in Arabia and rapidly migrated westwards (following prevailing palaeocurrents – Simmons & Bidgood, 2023, fig. 84 therein), with some morphological changes to create new species. Firm conclusions await the necessary taxonomic revisions derived from as yet unavailable data as highlighted in this paper.	en	Bidgood, Michael, Schlagintweit, Felix, Simmons, Michael (2024): The Genus Orbitolina D’Orbigny, 1850 (Larger Benthic Foraminifera) And Its Constituent Species: Notes On Identity And Stratigraphic Ranges. Acta Palaeontologica Romaniae 20 (2): 33-59, DOI: 10.35463/j.apr.2024.02.05, URL: https://doi.org/10.35463/j.apr.2024.02.05
