Mangashtia viennoti Henson, 1948c

Mangashtia viennoti Henson, 1948c View in CoL

Figure 15 View Fig

T 1948c Mangashtia viennoti n. gen, n. sp. Henson, p. 94-95, pl. XII, figs. 16-21; Cenomanian-Turonian, Iranian Zagros.

Non 1965 Mangashtia viennoti – Gollestaneh, p. 344- 348, pl. 104, figs. 1–2; pl. 105, figs. 1-6; pl. 106, figs. 1- 5; pl. 107, figs. 1-8; late Oxfordian-Kimmeridgian, Iranian Zagros. [= Levantinella egyptiensis Fourcade et al. 1997 ].

Non 1996 Mangashtia viennoti – Hughes, pl. 1 (pars); Kimmeridgian, Saudi Arabia. [= Levantinella egyptiensis ].

1997 Mangashtia viennoti – Fourcade et al., p. 183, figs. 5–6, 7.1–7.6; late Cenomanian? – Turonian, Iranian Zagros.

1998 Mangashtia viennoti – Whittaker et al., p. 48–49, pl. 71, figs. 1–4; late Cenomanian, Iranian Zagros. Explanation for the late Cenomanian age attribution is not given.

Non 2004a Mangashtia viennoti – Hughes, fig. 26 (8). Kimmeridgian, Saudi Arabia. [= Levantinella egyptiensis ].

2013 Mangashtia viennoti – Rahimpour-Bonab et al., fig. 8T; Turonian, Iranian Zagros.

2014a Biplanata peneropliphormis (sic) Hamaoui & Saint-Marc – Omidvar et al., pl. 1(I); Cenomanian-Turonian, Iranian Zagros.

2014b Mangashtia viennoti – Omidvar et al., fig. 4.1; Turonian, Iranian Zagros.

? 2014 Mangashtia viennoti – Afghah & Fadaei, labelled fig. 8g, but referring to fig. 9g; late Cenomanian, Iranian Zagros. [Effectively indeterminate, but possibly a fragment of Biplanata peneropliformis Hamaoui & Saint-Marc ].

Non 2016 Mangashtia viennoti – Rikhtegarzadeh et al., pl. 1, fig. 13; Cenomanian, Iranian Zagros. [Indeterminate biserial foraminifera].

? 2017 Mangashtia viennoti – Jamalpour et al., pl. 2, fig. h. Cenomanian, Iranian Zagros. [Effectively indeterminate but might be a fragment of Biplanata peneropliformis ].

2018 Mangashtia viennoti – BouDagher-Fadel, p. 306- 307; pl. 5.1, fig. 14; pl. 5.9, fig. 5. Cenomanian-Turonian, Iranian Zagros.

Non 2019a Mangashtia viennoti – Ghalandari et al., Pl. 1, fig. G; Jurassic, Persian Gulf. [= indeterminate, but not M. viennoti ].

Non 2019b Mangashtia viennoti – Ghalandari et al., text-fig. 7C; Jurassic, Persian Gulf. [= indeterminate, but not M. viennoti ].

? 2019 Biplanata peneropliformis Hamaoui & Saint-Marc – Kiarostami et al., pl. 2, fig. j; Santonian [erroneous label, probably Cenomanian], Iranian Zagros.

? 2021 Mangashtia viennoti – Bagherpour et al., fig. 12k; Turonian, Iranian Zagros.

? 2021 Mangashtia viennoti – Dousti-Mohajer et al., pl. 1, fig. h; early Turonian, Iranian Zagros.

2021 Cycledomia iranica (Henson) – Dousti-Mohajer et al., fig. 3l; early Turonian, Iranian Zagros.

2022 Cycledomia iranica – Esfandyari et al., fig. 25b; late Cenomanian?, Iranian Zagros.

Non 2022 Mangashtia viennoti – Dousti-Mohajer et al., fig. 5c; late Cenomanian, Iranian Zagros. [= Biplanata peneropliformis ].

2023a Mangashtia viennoti – Schlagintweit et al., p. 8, figs. 2E, 4A, C-F, 6, 7E-I; middle –?late Turonian, Iranian Zagros. [Probably can be restricted to mostly middle Turonian – Simmons et al., 2024a, b].

Non 2023a Mangashtia viennoti – Mehrabi et al., fig. 11(O); Santonian; Persian Gulf. [= new taxon to be described, Schlagintweit et al., 2024c].

Non 2024 Mangashtia viennoti – Moghaddam et al., fig. 2h; Cenomanian, Iranian Zagros. [= Biplanata peneropliformis ].

Reference Images: Fourcade et al. (1997); Schlagintweit et al. (2023a).

Taxonomy/Identity: First described from rather fragmentary material by Henson (1948c) from "Cenomanian-Turonian" limestones of the Izeh Zone of the Iranian Zagros, a detailed emended illustrated diagnosis for Mangashtia and the type species Mangashtia viennoti was published by Fourcade et al. (1997).

The test is compressed, discoidal with numerous annular chambers. Apertures are multiple, aligned in one row in the middle of the apertural face. The axes of the stolons are radial. Numerous subcylindrical or elongated pillars that are perpendicular to the septa are present in the central zone of the chambers. Pillars are aligned from one chamber to the next. The marginal zone of the chamber is not internally subdivided. The embryo of the megalospheric form consists of a globular proloculus with a simple wall.

Originally listed by Loeblich and Tappan (1987) in their “genera of uncertain status”, they noted that the genus is “unrecognisable” because many of the essential characters were not described by Henson (1948c). Fourcade et al. (1997) revised the genus based on the study of new topotype material, as well as specimens preserved in the F.R.S. Henson & Associates Collection housed in the Natural History Museum (London) and placed the genus in the subfamily Cyclopsinellinae . Critically, they recognised that Mangashtia lacks an initial planispiral stage as suggested by Henson (1948c).

Mangashtia differs from Cyclopsinella in the nature of the internal structure (pillars in the form of beams) and in its apertural characteristics (a single row of pores rather than a double row). Occasionally the Cenomanian species Pastrikella balkanica Cherchi, Radoičić & Schroeder has been confused with Mangashtia (Cherchi et al., 1976) , but it lacks pillars.

Fourcade et al. (1984) introduced Mangashtia? egyptensis for a form from the Late Jurassic of Egypt. Later ( Fourcade et al., 1997), this was taken as the type species of the new genus Levantinella . Although similar in some random sections to Mangashtia , Levantinella is peneropliform and compressed axially. A simple proloculus followed by a planispiral evolute stage and a later uniserial stage. Chambers contain internal structures in the form of “pillars” in the shape of a zigzag blade situated in the median plane of the chamber. In the marginal zone of the chamber, this pilaroid structure forms intercalating digitations between two apertures of the same row, but it never reaches the lateral wall. Subepidermal partitions are absent. Apertures are aligned in rows that alternate from one side of the equatorial plane to the other. Thus, Levantinella differs from Mangashtia in the presence of a planispiral stage and in the presence of multiple apertures in alternating rows. L. egyptensis is the identity of the taxon described from the Jurassic but ascribed to M. viennoti (e.g., Gollesstaneh, 1965; Hughes, 1996, 2004a, b).

The taxonomy of this species has undergone a relatively complex pathway and was once proposed to be the possible senior synonym of Biplanata peneropliformis ( Whittaker et al., 1998) but Schlagintweit et al. (2023a) and Simmons & Bidgood (2023) disagreed with that opinion and regard the two species as distinctly separate, although certain views in random thin-sections do show superficial similarities (see Schlagintweit et al., 2023a, for comparative illustrations). Nevertheless, records in the literature where the two species have been mistaken for one another occur and which has complicated evaluation of M. viennoti 's stratigraphic distribution. Mangashtia has many annular chambers and Biplanata is entirely planispiral (and later uncoiled). The periphery of B. peneropliformis is also much more angular than that of M. viennoti and the test thickens towards the periphery. Fourcade et al. (1997) suggested a clear stratigraphic separation of the occurrence of B. peneropliformis (Cenomanian) and M. viennoti (Turonian) in their studied section from the Iranian Zagros.

Confident Stratigraphic Range: early to middle Turonian.

Uncertain Stratigraphic Range: late Cenomanian, Coniacian – Santonian.

First described from the undifferentiated “Cenomanian-Turonian” Sarvak Formation of Iran by Henson (1948c), a detailed emended description by Fourcade et al. (1997) somewhat refined the range as late Cenomanian? – Turonian. The biostratigraphy of the Sarvak Formation (and its regional equivalents) has long been debated ( Omidvar et al., 2014a, b; Bromhead et al. 2022; Schlagintweit et al., 2023a; Hosseini et al., 2024; Simmons et al., 2024a). Nevertheless, the youngest Sarvak Formation, where preserved, is early – middle Turonian. However, this is not commonly preserved in many areas due to a tectonic/eustatic-induced sea level fall in the middle Turonian ( Schlagintweit et al., 2023a; Simmons et al., 2024a). Schlagintweit et al. (2023a) concluded that, with correct identification of M. viennoti , it is possible to equate the range of M. viennoti with the Wynd (1965) assemblage zone (biofacies) 29, and which is "most likely Turonian" ( Wynd, 1965) or intra-Turonian (i.e. no younger than middle Turonian in age ( Simmons et al., 2024a) and represents the youngest preserved Sarvak Formation. Schlagintweit et al. (2023a) defined a Reticulinella ? – Mangashtia foraminiferal association (Zone 29b) in recognition of this.

Purported records of M. viennoti from the Cenomanian part of the Sarvak Formation or its regional equivalents (often unverified by illustration) should mostly be treated with caution (e.g., Afghah & Fadaei, 2014 illustration indeterminate; Jamalpour et al., 2017 illustration indeterminate; Dousti-Mohajer et al., 2022 and Moghaddam et al., 2024 illustrated but incorrectly identified). An exception is the record of “ Cycledomia iranica ” by Esfandyari et al. (2022). This is, in fact, a specimen of M. viennoti . Unfortunately, there is no clear definition of where in the Sarvak Formation this specimen was recovered from, but much of the associated fauna is late Cenomanian. Whittaker et al. (1998) regarded the types of M. viennoti as being of late Cenomanian age but gave no explanation for their reasoning. Records of “ Mangashtia sp. ” from the probable late Cenomanian Mishrif Formation of Kuwait (El-Naggar & Al-Rifaiy, 1973) are not this genus, and are possibly Cycledomia .

Records from sediments younger than Turonian are also doubtful (e.g., from the Santonian of the Persian Gulf – Ilam Formation – by Mehrabi et al., 2023a, illustrated but identification doubted – Schlagintweit et al. 2024c). Abdolahi et al. (2024) reported but did not illustrate M. viennoti from the Turonian uppermost Sarvak Formation and the overlying Santonian Ilam Formation in a well from the Dezful Embayment of the Iranian Zagros.

Geographic Distribution: Restricted to the Arabian Plate/Zagros region. The species is apparently absent from the circum-Mediterranean region (e.g., Velić 2007; Chiocchini et al., 2012; Frijia et al., 2015; Schlagintweit et al., 2023a).