Pseudonummoloculina? ex. grp. heimi, Calvez, 1988

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 : 94-98

Pseudonummoloculina? ex. grp. heimi ( Bonet 1956, emmend. Conkin & Conkin, 1958)

Reference Illustration & Description

Conkin & Conkin (1958), pl. 1, text figs. 1-25, p. 152- 156.

In addition to the correct generic classification of nummoloculinids in general, a separate issue relates to the status of the species heimi . Nummoloculina heimi was first described from the Albian-Cenomanian of Mexico by Bonet (1956). Bonet’s descriptions and illustrations were – according to Conkin & Conkin (1958) – unsatisfactory, and they emended the definition based on their own material which was also from Mexico and from the southern United States of America. Some of this material came from the same lithostratigraphic unit in Mexico as Bonet’s, but not from the same (type) locality.

Conkin & Conkin (1958) recognised two macrospheric morphotypes, essentially: (i) with a quinqueloculine nepionic stage followed by a planispiral coil and (ii) planispirally coiled throughout.

Subsequent studies by Hottinger et al. (1989) from Mexico resulted in them attributing forms to heimi (“as revised by Conkin & Conkin, 1958 ”) characterised by an early streptospiral (not quinqueloculine) stage followed by whorls which gradually stabilised their coiling axis without becoming completely stable; part of their so-called “stem miliolids” ( Hottinger et al., 1989; p. 103).

A separate but related issue also arises over the nature of the aperture. The presence of folds or notches/crenulations in the aperture is fundamental (among other things) for a generic assignment to Pseudonummoloculina . Neither Bonet (1956) nor Conkin & Conkin (1958) observed such features in their North American material. Hottinger et al. (1989) only observed a row of notches in one illustrated specimen [see Fig. 44 (right) herein] of a near-completely planispiral form but not observed at all in specimens with initial streptospiral coiling. Piuz and Vicedo (2020) tentatively suggested assigning this specimen to their new nummoloculinid species – Nummoloculinodonta akhdarensis thus removing any suggestion of notched/crenulated apertures as a characteristic of heimi forms. However, Solak et al. (2021) contradict this by stating “… the widespread Cretaceous species Nummoloculina heimi Bonet, 1956 , with a clear notched aperture ( De Castro, 1987; Hottinger et al., 1989) was transferred to Pseudonummoloculina ”. It should be noted that Solak et al. (2021) did not themselves observe the notched aperture in their own material either. De Castro’s material from the Cenomanian of Apennine Italy shows one specimen (out of 4 examples) which shows an aperture with “wavy margins”. Hottinger et al. (1989) ’s material from the Cenomanian of Mexico shows a single specimen (out of several tens of examples) with “notches in distal apertural margin”. This particular specimen (a subaxial section, bottom right corner of pl. 22, fig. 6 – see Figure 44 b ) is very similar to Fig. 48b herein for P? cf. irregularis .

Piuz & Vicedo (2020) discussed the implications of these observations (and others) and concluded that “…the different morphotypes mentioned above as P. heimi [are] likely separate taxa”. However, both they and we agree that many forms displaying this variety of morphological characteristics have been attributed to heimi in the literature and that a comprehensive revision is required. The solution would require the adequate stratigraphic separation of similar morphotypes to determine if relationships were evolutionary or of intra-specific variability.

We agree in part with Piuz & Vicedo’s (2020) proposal to restrict heimi sensu stricto to the morphotypes described by Bonet (1956) and Conkin & Conkin (1958) – essentially the North American specimens – although recognising that these themselves may comprise several separate taxa. Their characteristics are:

• compressed axially and lacks umbilical axial thickening

• small quinqueloculine nepionic stage (max 4 whorls/8 chambers)

• numerous planispiral whorls (up to 7)

• numerous chambers per whorl (6 up to 16)

• aperture with “stocky tooth” but no notch/ridge/crenulations

Our observations suggest that, in the majority and possibly all cases, forms attributed to heimi in Europe/Africa/Middle East do not appear to conform wholly to these criteria and that further taxonomic revision is required to determine if they are – as we suspect - additional, separate taxa. Some may be attributable with further research to Nummoloculinodonta akhdarensis , others to P.? regularis sensu Chiocchini et al. , or a completely new species. Such work is beyond the scope of this article, and we have therefore, reluctantly, placed heimi in open nomenclature (“ex gr.”) and assigned it to an unsatisfactory genus, as a problem to be solved in the future.

P.? heimi is more axially compressed than P. aurigerica , has more numerous planispiral whorls and chambers per whorl and does not appear to have notches or crenulations.

Despite having fewer chambers in each post-embryonic whorl (3-5 cf. 6-16) P.? regularis sensu Chiocchini et al. can also appear similar in some random section orientations with a similar number of post embryonic planispiral coils (up to 7), although unlike P.? ex. grp. heimi , P.? regularis sensu Chiocchini et al. is planispiral virtually throughout its growth.

Stratigraphic Distribution

(late Aptian?) Albian – Cenomanian (?Turonian and younger).

Notwithstanding the comments made above, an evaluation of published records suggests P.? ex grp. heimi is widely distributed with the majority from Albian-Cenomanian strata. Many records are accompanied by illustration but some of these illustrations do not necessarily confirm identity. In addition, the generic assignment ( Pseudonummoloculina or Nummoloculina ) varies between authors. The upper age limit of this species is difficult to pinpoint although an extension into the Turonian appears possible. Records above this level need further evaluation (e.g., Tsaila-Monopolis, 1977).

Pseudonummoloculina? heimi was first described from the Albian – Cenomanian El Abra formation of Mexico ( Bonet, 1956). Conkin & Conkin’s (1958) material was from Mexico (El Abra Formation), and Texas (Devil’s River, Edwards and Glen Rose Formations) and Florida (Fredericksburg Formation) of the USA (see also Applin & Applin, 1965).

Other confirmed illustrated records of this species from Mexico include Rosales-Dominguez (1989); Rosales-Dominguez et al. (1997) and Omaña et al. (2013, 2019) respectively from the Albian – early Cenomanian Sierra Madre Formation and the Albian – Cenomanian El Abra Formation. Scott & Gonzalez-Leon (1991) recorded the species from the middle Albian Espinazo del Diablo and Nogal formations of the Lampazos region. Unillustrated records include Ontiveros-Tarango (1973; Cenomanian); Hernández-Romano et al. (1997; late Cenomanian); Cros et al. (1998; Cenomanian); Aguilera-Franco et al. (2001) and Aguilera-Franco (2003) (from the middle – late Cenomanian); and Aguilera-Franco & Allison (2004; undated) from the Morelos Formation. However, the illustration in Aguilera-Franco (2000) is not identifiable at species level but appears incompatible with P.? ex. grp. heimi as described herein. Lucas et al. (2015) provided an illustrated record from New Mexico.

Ashworth (1974); Caceres Flores (2016) and Radmacher et al. (2021) have plausible illustrated records from the Albian – Cenomanian Coban Formation of Guatemala (see also Fourcade et al., 1999, unillustrated, but Albian). However, the record by Moeschler (2009) is probably not this species (it may be Spiroloculina sp. ). Ayala-Castañares & Furrazola-Bermúdez (1962) provide excellent illustrations of this species from the Albian – Cenomanian of Cuba, whilst Diaz Otero et al. (2001) records but does not illustrate this species. Rogers et al. (2007) report the species from the Albian of Honduras.

In Western Europe records from Portugal by Berthou (1973) and Andrade (2018) are illustrated but the illustration cannot be confirmed as P.? ex. grp. heimi . Records by Berthou & Lauverjat (1979) and Crosaz-Galletti (1979) are unillustrated. Most assign a middle – late Cenomanian age.

Records from Italy are numerous ( De Castro (1965; 1987 – see comments above regarding synonymy with N. akhdarensis ); Borghi & Pignatti (2006); Consorti et al. (2015); Crescenti (1969); Di Stefano & Ruberti (2000); Spalluto & Caffau (2010) and Spalluto (2011)) but only the record of Spalluto & Caffau (2010) is confirmed by illustration. Ages assigned are from early – late Cenomanian, but Crescenti (1969) indicates this species ranges up to the “Senonian” (see also Tsaila-Monopolis, 1977 from Greece). Parente et al. (2010) provide an unillustrated record of “ Nummoloculina cf. heimi ” from the late Turonian. Chiocchini and Mancinelli (1977) mention the species as having biozonal value for the Turonian of the Apennines, but perhaps like other records, this may be because of loose use of the species concept of heimi . In subsequent papers (e.g., Chiocchini et al., 2008), the zonal index is called “ Nummoloculina cf. irregulari s”. This may explain the illustrated Turonian record of “ Nummoloculina cf. heimi ” by Foglia (1992).

Records from Slovenia and the Balkans (mainly Croatia) are also numerous (e.g., Radoičić, 1965, illustrated from Cenomanian strata). Koch et al. (1998) from Slovenia illustrates a form which is possibly P.? ex. grp. heimi from the Cenomanian – Turonian and Jez et al. (2011) records unillustrated material from the late Cenomanian. Croatian records are more numerous with illustrated records: Husinec & Sokač (2006) (illustrated as “ Pseudonummoloculina sp. ” but mentioned as Pseudonummoloculina heimi in the text and range charts - Albian), Tešović et al. (2011) from the early – late Albian, and Velić & Sokač (1979) undated. The illustrated records of Ritossa (2018), also undated, and Brčić et al. (2021) (late Cenomanian) cannot be verified as this species. Additional records unconfirmed by illustration include Brčić et al. (2017); Husinec et al. (2000, 2009); Tišljar et al. (1998); Velić (2007); Korbar & Husinec (2003), and Velić & Vlahović (1994). Assigned ages range from the early Albian to the early Campanian (e.g., Velić, 2007). A record from the late Turonian – Coniacian of Croatia ( Gušić et al., 1988) is a nummoloculinid, but difficult to assign to a species. A single record from Montenegro ( Božović, 2016) is unillustrated and has no assigned age.

Most records from Greece (e.g., Fleury, 1971; Decrouez, 1976, 1978; early – late Cenomanian) are unillustrated, but that of Charvet et al. (1976) is, but might be P.? regularis sensu Chiocchini et al. or Nummoloculinodonta akhdarensis . Tsaila-Monopolis (1977) illustrated the species from the “Cenomanian - Turonian” and “Senonian” of Greece. Some illustrations are more compatible with P.? regularis sensu Chiocchini et al. (2012) . Another record from Greece (Zambetakis-Lekkas, 2006) is unillustrated and is said to range from the late Cenomanian to the Maastrichtian, although that seems unlikely. Zambetakis-Lekkas et al. (2006) also records the species (unillustrated) from Crete and assigns the same age range.

North Africa records include from Tunisia ( Bismuth et al., 1967; Saïdi et al., 1995 and Touir et al., 2017). Only the former record is confirmed by illustration and may include P.? regularis sensu Chiocchini et al. (2012) but all authors assign a Cenomanian age. By contrast, Lüning et al. (2000) report the species from the Kufra Basin of Libya and assign a Campanian? – Maastrichtian age, although they provide no illustration but note that “ the present specimen is similar to those described in Hottinger et al. (1989, pl. 22, fig. 6) and by Calvez (1988); the only difference is the smaller size compared to the material described by Calvez. The specimen figured by De Castro (1987, fig. 3) also shows all features of the present material.” In this respect it is worth noting that Calvez (1988) did not illustrate P.? heimi , but P. aurigerica .

Numerous illustrated records occur from Turkey of which those of Sari et al. (2009) and Solak et al. (2020, 2021) are confirmed by illustration. The records of Ozkan & Altiner (2019), Solak (2021) and Solak et al. (2017, 2019) are also illustrated but the specimens are only possibly of this species. Most records are assigned a middle – late Cenomanian age although Solak et al. (2021) indicates an age as old as late Albian and Sari et al. (2009) an age as young as Coniacian. The record of Ozkan & Altiner (2019) is thought to be from the early Cenomanian. Sinanoglu (2021) provides an unillustrated record.

In the eastern Mediterranean area P.? ex. grp. heimi has been reported from Syria, Lebanon, and Israel, although confirmed by illustration only from the first two (i.e., Ghanem & Kuss, 2013, and Saint-Marc, 1974 a, 1981). Note the illustrated records of Ghanem et al. (2012) are insufficient to confirm their identity. Unconfirmed Israeli records are from Hamaoui (1965, 1966). All of these records are from throughout the Cenomanian, with Turonian records (e.g., Saint-Marc, 1970) being revisable as late Cenomanian (e.g., Saint-Marc, 1978). Mouty et al. (2003) have reported the species from the late Cenomanian of Syria.

Records from the Sarvak Formation of Iran and the Mishrif Formation in Iraq are numerous, especially from the former, but the quality of confirmatory illustrations is variable. Records with good or plausible illustration in the sense of P.? ex. grp. heimi include Esfandyari et al. (2023), Rahimpour-Bonab et al. (2013) and Mohajer et al., (2021b). Records with questionable or no illustration include Assadi et al. (2016) (probably P.? regularis sensu Chiocchini et al. ); Daneshian et al. (2016); Kiarostami et al. (2019); Saeedi Razavi et al. (2019, 2021); Mohajer et al. (2022b); Omidvar (2014a); Rikhtegarzadeh et al. (2016, 2017) and Al-Salihi & Ibrahim (2023). Even though considered of biozonal value by the authors, the illustrations of P.? ex. grp. heimi (as Nummoloculina heimi ) by Afghah et al. (2014) and Afghah & Fadaei (2014) cannot be confirmed as being of this species. The illustration by Afghah & Dookh (2014) is of an alveolinid. These records are predominantly assigned a Cenomanian age, although Rahimpour-Bonab et al. (2013) provide a combined total range of late Albian – Turonian. An illustrated record by Gollesstaneh (1965) from the “late Aptian – early Albian” of the Iranian Zagros, represents one of the oldest records of this species sensu lato.

Records from Iraq are fewer and include illustrated forms by Al-Dulaimy & Al-Sheikhly (2013) which are possibly P.? ex. grp. heimi . Illustrations by Al-Dulaimy et al. (2022) from the late Cenomanian Mishrif Formation may well be alveolinids.

Additional unillustrated records occur from the Natih Formation of Oman ( Kennedy & Simmons, 1991; Simmons & Hart, 1987) and are assigned a middle – late Cenomanian age.

Cenomanian Paleogeographic Distribution

Pan-Neotethyan, America and the Caribbean.

See references above. As a note, pre-Cenomanian records can be extended further since Arnaud-Vanneau & Premoli-Silva (1995) note that their “ Nummoloculina sp. ” recorded from the late Albian (?) of MIT Guyot in the Pacific is very similar to P.? ex. grp. heimi .

Figures

Fig. 44 Pseudonummoloculina heimi (Bonet) left – after De Castro (1987: fig. 3-2) and right –after Hottinger et al. (1989: pl. 22, fig. 6-part). Both specimens purported to show notched apertures. Neither specimen can, however, be attributed to heimi based on the criteria established by Piuz & Vicedo (2020, see text). Those authors place both specimens in tentative synonymy with their new species Nummoloculinodonta akhdarensis.

Fig. 48 Representative illustrations of Pseudonummoloculina? cf. irregularis: a Subequatorial section, Chiocchini et al. (2012, pl. 1, fig. 3, Italy); b Subaxial section, Chiocchini et al. (2012, pl. 120,fig. 2, Italy); c Subequatorial section, Chiocchini et al. (2012, pl. 120, fig. 4, Italy); d Pseudonummoloculina sp. sensu Solak et al. (2020, fig. 14V, Turkey).