Pseudonummoloculina? regularis ( Philippson, 1887 ) sensu Chiocchini et al. 2012

SIMMONS, MICHAEL & BIDGOOD, MICHAEL, 2023, “ Larger ” Benthic Foraminifera Of The Cenomanian. A Review Of The Identity And The Stratigraphic And Palaeogeographic Distribution Of Non-Fusiform Planispiral (Or Near-Planispiral) Forms, Acta Palaeontologica Romaniae 19 (2), pp. 39-169 : 98-101

Pseudonummoloculina? regularis ( Philippson, 1887) sensu Chiocchini et al. 2012

Reference Illustration & Description

Chiocchini et al. (2012), pl. 83, figs. 2-8.

Nummoloculina regularis Philppson , a species first described from Late Cretaceous marls in the region of Lake Wolfgang, Austria ( Philippson, 1887), is often referred to from Cenomanian strata in the literature (as Nummoloculina or Pseudonummoloculina ), but Schlagintweit (2008) has discussed the identification, taxonomy and distribution of Philippson’s specimens and restricts its occurrence (in Austria at least) to no older than the late Turonian. Schlagintweit (2008) believes the specimens described and illustrated by Phillippson (1887) are better attributable to Vidalina hispanica Schlumberger , and, as first pointed out by Radoičić (1978), are not the same as those specimens variously assigned to regularis in the Cenomanian of other localities around Neotethys in having no true septa (in any case it is believed Phillippson’s types are lost so confirmation is impossible – Dr Lorenzo Consorti, pers. comm., 2023). If (hypothetically) correct (see Piuz & Vicedo, 2020 for discussion), the new combination – Vidalina regularis (Schlumberger) would become the type species of the genus Vidalina . However, Schlagintweit (2008) does not speculate on what this means for Cenomanian specimens attributed to the species regularis (nor do Piuz & Vicedo, 2020).

See the Species Key Chart (Appendix) for diagnostic and other characteristics.

The best illustrations of what we refer to as regularis which are demonstrably Cenomanian are from Chiocchini et al. (2012) figured herein. Assigned by them to Nummoloculina , they are, for the present, here questionably (and pending review) assigned to Pseudonummoloculina in the same way as P? heimi , as Nummoloculina is not a Cretaceous genus. Thus herein we discuss Pseudonummoluculina? regularis sensu Chiocchini et al. (2012) . These are comparable with Nummoloculina sp. ( aff. regularis ) as described and illustrated by Radoičić (1978).

As its name suggests, P.? regularis begins coiling planispirally in a single plane from very early on in the post-embryonic stage. In axial views a post-prolocular milioline stage is either very small or absent. In this respect it is also similar (in axial view) to Vidalina radoicicae .

P? regularis has a similar equatorial profile to P? heimi but with many fewer chambers per (later) whorl (3-5 cf. 6-16), as well as more regular planispiral coiling. P. gnosi has a more biconvex axial profile with more umbilical thickening and devlops ribs/notching, although P. gnosi and P? regularis appear to share a lack of a distinctly milioline early stage.

P. aurigerica is more inflated and biconvex in axial profile compared with P? regularis and with a more lobate periphery. It also posesses apertural notches/crenulations (caused by ribs in the chamber roof).

Stratigraphic Distribution

Early Cenomanian - late Cenomanian (?early Turonian).

The material of Chiocchini et al. (2012) is from the early Cenomanian in the concept of those authors, which may include part of the middle Cenomanian of the current international standard. Elsewhere in western Europe, the following records may refer to P.? regularis sensu Chiocchini et al. : Cenomanian of Portugal (Berthou, 1978; Berthou and Lauverjat, 1979; Crosaz-Galletti, 1979; Andrade, 2018), Spain (Cherchi & Scroeder, 1998) and Italy ( Chiocchini, 2008a). With the exception of Andrade (2018), these records are unillustrated. Bilotte (1984) illustrated N. regularis from the Pyrenenes, but the specimens are large (up to 2.1 mm) and broad in axial profile, making comparison to P.? regularis sensu Chiocchini et al. uncertain.

Records from eastern Europe, Greece and the Balkans area are numerous (mostly middle – late Cenomanian) but are all unillustrated apart from Radoičić (1974a & b, 1978) (as “ Nummoloculin a cf. regularis ” and Nummolulina sp. ( aff. regularis )”) from the late Cenomanian –?early Turonian of Serbia, Schlagintweit & Rigaud (2015) from the upper middle – late Cenomanian of Kosovo and Tsaila-Monopolis (1977) from the “Cenomanian – Turonian” of Greece. The unillustrated records are from Albania ( Consorti & Schlagintweit, 2021a); Croatia ( Husinec et al., 2000, 2009; Tišljar et al., 1998; Velić & Vlahović, 1994; Velić, 2007); Greece / Crete ( Decrouez, 1976, 1978; Fleury, 1980; Zambetakis-Lekkas, 2006; Zambetakis-Lekkas et al., 2006; Pomoni-Papaioannou & Zambetakis-Lekkas, 2009) and Slovenia ( Šribar & Pleničar, 1990; Jez et al., 2011). An illustration by Fleury (1971) from Greece is most likely Vidalina radoicicae .

Records from North Africa are comparatively rare but with an uncertain illustration from the late Cenomanian of Morocco ( Ettachfini, 1993) and an unillustrated record from the late Cenomanian of Tunisia ( Touir et al., 2017).

Solak et al. (2020) provides illustrated records from throughout the Cenomanian of the Turkish Taurides. Sari et al. (2009) also provides an illustration from a section assigned to the middle Cenomanian – Turonian, but this specimen, though regularly planispiral, appears axially too broad to be definitely assigned to this species and is most likely a different taxon. Other records from Turkey include Solak et al. (2015) and Koç (2017) but are unillustrated. They are assigned age ranges of Cenomanian – Conician and Cenomanian –?early Turonian respectively.

In the eastern Mediterannean area illustrated records are found from Lebanon ( Saint-Marc, 1974 a, 1981) and Syria ( Ghanem et al., 2012 (uncertain); Ghanem & Kuss, 2013). As noted by Radoičić (1978), the dimensions mentioned by Saint-Marc (1974a) are small for the Cenomanian form of P.? regularis , but the illustrations in both his 1974 and 1981 paper indicate a larger size which is compatable. Saint-Marc (1978, 1981) regarded the species as having a late middle – late Cenomanian range. Records from the Naur (b-d) Formation in Jordan (Schulze, 2003; Schulze et al., 2004) are unillustrated.

Records from the Sarvak Formation of the Iranian Zagros are relatively numerous with several confirmed by illustration. These are Afghah et al. (2014); Dehghanian & Afghah (2021); Esfandyari et al. (2023); Kiarostami et al. (2019); Mohajer et al. (2021b); Parnian et al. (2019); Saeedi Razavi et al. (2019) and Saeedi Razavi et al. (2021). An illustration by Afghah & Fadaei (2014) (note transposition of plate captions) is uncertain, whilst “ Nummoloculina sp. ” as illustrated by Sampò (1969) may, questionably, be this species, as might the illustration of “ Nummoloculina sp. ” by Ahmadi et al. (2008). However, illustrations by Rahimpour-Bonab et al. (2013) [= Pseudonummoluculina? cf. irregularis sensu Chiocchini et al., 2012 ], Omidvar et al. (2014a) [= Pseudonummoluculina? cf. irregularis sensu Chiocchini et al., 2012 ], and Rikhtegarzadeh et al. (2016) [indeterminate nummoloculinid] are probably not this species, whilst the illustration by Afghah & Dookh (2014) is of an alveolinid. Assigned ages are Cenomanian. Unillustrated records by Fourcade et al. (1997) and Shapourikia et al. (2021) are middle - late Cenomanian.

An unillustrated record from the Cenomanian Natih Formation of Oman is also noted by Rabu (1993).

In the Caribbean area P.? regularis sensu Chiocchini et al. has been recorded from the late middle – late Cenomanian of Mexico with illustration by Aguilera-Franco (2000) and Aguilera-Franco et al. (2001) (see also Aguilera-Franco, 2003; Aguilera-Franco & Allison, 2004 and Michaud et al., 1984 but without any illustration). It has been questionably illustrated from Guatemala by Moeschler (2009).

Cenomanian Paleogeographic Distribution

Neotethys and Caribbean.

See above references.