Charentia cuvillieri Neumann 1965

Charentia cuvillieri Neumann, 1965

Reference Illustration & Description

Arnaud-Vanneau in Schroeder & Neumann (1985), Pl. 3, p. 17-18. See also Loeblich & Tappan (1985), Pl. 3, p. 6 and Maksoud (2015) Pl. 41, p. 134-138 (with extensive synonymy list, especially of Early Cretaceous occurrences).

The genus Charentia was introduced by Neumann (1965) and has a broad planispiral, lenticular test similar to Mayncina but often with a late uncoiled portion of up to 4 rectilinear chambers, following 11-13 chambers in the last whorl of up to 4 whorls. Internally the wall structure is pseudokeriothecal (see excellently illustrated material and description by Hottinger (1967) of material from the Cenomanian of Spain) with an imperforate outer layer similar to that seen in the subglobular Moncharmontia although Charentia is more lenticular and tends to uncoil (and also possesses a different apertural type). Rather thin septa with a build-up at the base of each (= characteristic chomata-like nodes, Loeblich & Tappan, 1985, p. 98) and the aperture varies in shape with ontogeny – a triangular arch progressing to a 3-prong opening with the “vertical” part of the opening becoming longer and ending in a narrow slit along the apertural face. This can be seen in rare external views of Cenomanian material from Egypt (Hassanien & Sigal, 1983) and Somalia (Luger, 2018). Nautiloculina Mohler is similar but has a simpler (i.e., non pseudokeriothecal) wall and noticeably thicker septa. See the Species Key Chart (Appendix) for diagnostic and other characteristics.

Loeblich & Tappan (1985) provide a useful review of synonyms of Charentia and C. cuvillieri.

The Late Jurassic genus Tonasia Gorbachik is considered as a synonym of Charentia (see discussion of the type species Tonasia evoluta Gorbachik below), whilst Hemicyclammina praesigali Banner (see below) from the Aptian – Albian of Spain is considered a synonym of C. cuvillieri. They note that the Barremian – Aptian genus Melathrokerion Brönnimann & Conrad is similar to Charentia by virtue of its pseudokeriothecal wall and general morphology, but has a thicker wall, a more nautiloid shape, fewer chambers per whorl, and a broadly rounded periphery. Cribrostomoides paralens Omara described from the Cenomanian of Egypt (Omara, 1956) is referred to Charentia by Loeblich & Tappan (1985). If it proves to be a synonym of C. cuvillieri it will have priority (access to type material is being sought at the time of writing).

A superficially similar form to C. cuvillieri is Everticyclammina greigi (Henson) which is clearly distinguished by its alveolar wall (Banner & Higton, 1990). Additionally, E. greigi is less inflated and the chamber sutures are more consistently depressed. Comaliamma Loeblich & Tappan is superficially similar to Charentia in the discoid early stage and tendency to uncoil but differs in the nature of the aperture and simple rather than canaliculate walls and septa.

Arnaud-Vanneau in Schroeder & Neumann (1985) identifies two morphotypes of C. cuvillieri – one large (1.2 – 1.4 mm equatorial diameter) with a thicker wall; the other small (0.780 – 0.830 mm equatorial diameter) with a thinner wall and fewer chambers (9-11) in the last whorl. Material described by Hofker (1965) from the Aptian – Albian of Spain as Haplophragmoides greigi (Henson) and later as Hemicyclammina praesigali Banner (Banner, 1966) conforms to C. cuvillieri sensu lato, suggesting that the smaller morphotype (0.6-0.8 mm cited diameter) might have a pseudokeriothecal wall texture. Small morphotypes of C. cuvillieri were described by Gollestaneh (1965) in an unpublished Ph.D. thesis as “ Haplophragmoides persica n. sp. ” from the Barremian – Aptian of the Iranian Zagros belt (Schlagintweit, 2015).

The two forms also appear to have different ranges with small forms found from around the Jurassic/Cretaceous boundary (e.g., Altiner, 1991; Schlagintweit & Ebli, 1999; Ivanova & Kolodziej, 2004; Chiocchini et al., 2012; Kobayashi & Wernli, 2014; Bucur et al., 2014, 2020) to the Cenomanian, and the larger forms from the Cenomanian only. However, a full taxonomic review of the many reported occurrences of the species and its possible synonyms from the latest Jurassic to mid-Cretaceous is required to confirm this stratigraphic separation.

Some small specimens have been tentatively recorded from the Late Jurassic – Early Cretaceous as Charentia evoluta (Gorbachik) (= Tonasia evoluta) (e.g., Bucur et al. (1996) from Italy; Krajewski & Olszewska (2007) from Crimea; Kobayashi & Vuks (2006) from Japan and Pleş et al. (2015) from Romania) although Schlagintweit & Wagreich (2005: p. 117) state that these small morphotypes “can hardly be distinguished from C. cuvillieri ”. Records of Charentia spp., including C. evoluta from the mid-Cretaceous of central Iran (Rahiminejad & Hassani, 2015, 2016) require further investigation. Most illustrations are potentially of haplophragminids, small and lacking any form of distinctive wall structure.

Charentia nana Arnaud-Vanneau is a very small species of Charentia (equatorial diameter 0.365 – 0.480 mm) (Arnaud-Vanneau, 1980) that is even smaller than the small forms of C. cuvillieri, and with only 2.5 – 3 whorls and 7.5 – 8 chambers in the last whorl. A pseudokeriothecal wall structure remains to be demonstrated for this species.

Radoičić (1974a) described a new species from the late Cenomanian of Kosovo called Charentia kosovica which she said differed from C. cuvillieri by having a more rounded test, being slightly smaller and having fewer (9- 10) chambers in the whorl. This corresponds somewhat with Arnaud-Vanneau in Schroeder & Neumann’s (1985) description of the smaller morphotype (see above), but the latter’s illustrations of the smaller form show a smooth, but clearly more angular periphery in axial view, leading to a lenticular test. Radoičić’s specimens have well-rounded peripheries (see also Saint-Marc, 1974a: pl. 1, fig.11) and a much less lenticular profile. Nonetheless, Rey et al. (1977) placed C. kosovica in synonymy with C. cuvillieri, which if correct, provides evidence for a late Cenomanian age for this species (see below). Arnaud-Vanneau in Schroeder & Neumann (1985) does not mention C. kosovica (i.e., she does not synonymise it with any other taxon). Specimens illustrated by Weidich & Al-Harithi (1990) from the Albian of Jordan as Charentia cf. cuvillieri and compared to C. kosovica do not appear to be Charentia. They possess large, broad chambers, separated by short septa, with a marked basal layer. More research is required to assess their identity.

Charentia hasaensis Basha and Charentia rummanensis Basha are poorly known species introduced from material from the late Cenomanian of Jordan (Basha, 1978). They appear to have only been mentioned in their type descriptions. From the limited illustrations they may be partly synonymous with Hemicyclammina whitei (Henson). Another species from the same publication, Mayncina hasaensis Basha might have closer affinity with C. cuvillieri. The type material of all these species needs to be re-examined. Likewise, Charentia granulosa Kerdany & Eissa, described from the late Cenomanian of Egypt (Kerdany et al., 1973), may include H. whitei amongst its types.

Stratigraphic Distribution

Latest Jurassic – late Cenomanian.

C. cuvillieri was originally described from the middle Cenomanian of western France (Neumann, 1965) and was described as ranging from Albian and older to the top of that substage by Schroeder & Neumann (1985). A range chart in Saint-Marc (1981) gave the Neotethyan range of this species to be throughout the Cenomanian, but gave an Albian restricted-range for its occurrence in Lebanon (although the text indicates extension into the earliest Cenomanian). Illustrations in Saint-Marc (1974a) suggest that it is the “small” form of C. cuvillieri (equatorial diameter <0.525 mm) that is being referred to for the Lebanese occurrences. As noted by Arnaud-Vanneau (1980) they may be comparable with her species C. nana. Since the publications of Saint-Marc (1981) and Schroeder & Neumann (1985) there have been a great many records of the species published (although relatively few with plausible illustration) and these confirm that the species if treated sensu lato pending a full taxonomic study of the genus is long ranging from around the Jurassic/Cretaceous boundary to the top of the Cenomanian. A middle Turonian record (Cherif et al., 1989) from Egypt is not this species. The external-only views are difficult to determine, but the test lacks the broad, lenticular profile of C. cuvillieri.

It is possible that Charentia can be found in strata younger than Cenomanian. Luperto-Sinni (1976) and Luperto-Sinni & Richetti (1978) illustrated specimens termed “ Navarella ? Sp.” from the Santonian and Maastrichtian of southern Italy. These are undoubtedly not Navarella Ciry & Rat and were considered as synonymous with specimens termed Lituola ? Sp. from the Coniacian-Santonian of Austria (Schlagintweit, 1992). Some of the Austrian specimens have hints of a pseudokeriothecal wall. Despite gross morphological similarities with Charentia, more material and research are required before drawing any conclusions regarding range extension.

Late Cenomanian occurrence is demonstrated by Ettachfini & Andreu (2004) from Morocco (see also unillustrated by Ettachfini et al., 1989, 2005; Lézin et al., 2012). If C. kosovica proves to be a synonym of C. cuvillieri (see above), this provides further support for a late Cenomanian age. Other illustrated late Cenomanian records are less dependable. A specimen illustrated from Egypt by El-Sheikh & Hewaidy (1998) cannot be confirmed from the illustration provided which looks close to Hemicyclammina whitei (Henson). Nonetheless, the species has been plausibly illustrated from the Cenomanian of Egypt (Hassanien & Sigal, 1983). A late Cenomanian illustration of Charentia sp. from southern France by Rineau et al. (2021) is completely unrelated to this genus – it appears to be an indeterminate, but simple trochospiral taxon.

Other relatively biostratigraphically well-constrained records from the Cenomanian include Schlagintweit & Wagreich (2005) from the early Cenomanian of Austria; Simmons et al. (2020b) from the middle Cenomanian of south-east Turkey; and Aguilera-Franco (2000) from Mexico. A single specimen illustrated by Ghanem et al. (2012) from the early Cenomanian of Syria is probably C. cuvillieri but cannot be confirmed. Dr. Ian Sharp (pers. comm.) has provided the authors with a plausible illustration of C. cuvillieri from the lower Sarvak Formation of the Iranian Zagros and hence early Cenomanian in age (Bromhead et al., 2022) (see also unillustrated from the Zagros by Kiarostami et al. (2019) and Omidvar et al. (2014a, b).

Berthou (1973) recorded and illustrated this species from the early Cenomanian of Portugal, but the illustrations are poor. Rey et al. (1977) illustrated the species from what they termed late Albian strata, although based on the orbitolinids present from the same beds, the age could well be early Cenomanian at least in part (see Berthou & Schroeder, 1978). Later Berthou and Lauverjat (1979) revised the range in Portugal to early Albian to top Cenomanian (unillustrated, see also Rey, 2009), and then Berthou (1984b) extended the range into the early Turonian but provided no further illustrations (see also Andrade (2018) with uncertain illustration).

Cenomanian Paleogeographic Distribution

Neotethys and Caribbean.

A plausible illustrated record from the Cenomanian of the Tajik Basin (Central Asia, Kaya, 2020) represents an interesting palaeogeographic extension to the distribution of this species (see also Kaya et al., 2020). Dufaure et al. (1984) illustrated C. cuvillieri from the undifferentiated Cenomanian of Libya, close the border with Chad. It has been illustrated as Daxia cenomana from Armenia (Danelian et al., 2014) and from Tunisia (Abdallah et al., 1995) as Nummofallotia apula Luperto-Sinni (and as Charentia cf. cuvillieri) (see also unillustrated records by Bismuth et al. (1981) and Touir et al. (2017).

Additional unconfirmed (because of lack of illustration or uncertain illustration) occurrences in the Cenomanian include from Croatia and the Balkans (Husinec et al., 2000, 2009; Velić & Vlahović, 1994; Velić, 2007 and Radoičić & Schlagintweit, 2007); Greece (Steuber et al, 1993); Egypt (Kerdany et al., 1973; Bachmann et al., 2003; Abu-Zied, 2007; Ismail et al., 2009; Shahin & Elbaz, 2013, 2014; Orabi & Hamad, 2018; El Baz & Khalil, 2019); Levant (Bachmann & Hirsch, 2006); Spain (Cherchi & Schroeder, 1982; Calonge et al., 2002, 2003; Calonge García & López Carrillo, 2003; González-Fernández et al., 2004; Caus et al., 2009; Consorti, 2017; Consorti et al., 2014, 2016b; Gräfe, 2005; and Vicedo et al., 2011); Turkish Taurides (Solak et al., 2020); central Iran (Naraki et al., 2015); Mexico (Aguilera-Franco et al., 2001; Aguilera-Franco, 2003 and Omaña et al., 2019); Algeria (Laouidji & Hafiani, 2021, Slami et al., 2022); southern Iraq (Mohammed, 1996); and Oman (Simmons & Hart, 1987; Rabu, 1993).