Murgeina apula ( Luperto Sinni, 1968 )

SCHLAGINTWEIT, FELIX, YAZDI-MOGHADAM, MOHSEN & TEŠOVIĆ, BLANKA CVETKO, 2023, Upper Cretaceous Foraminifera Murgeina Apula (Luperto Sinni, 1968): A Methusalem And Cenomanian-Turonian Boundary Survivor Taxon, Acta Palaeontologica Romaniae 19 (2), pp. 25-38 : 29-34

Murgeina apula ( Luperto Sinni, 1968)

Figs. 3c , 5d , 6-7

The references from the Cenomanian are highlighted in bold letters.

*1968 Nummofallotia apula n. sp. – Luperto Sinni, p. 7, pls. 1-3.

1970 Nummofallotia apula Luperto Sinni – Hamaoui & Saint-Marc, pl. 33 pars.

1974 Numofallotia apula Luperto Sinni – Saint-Marc, p. 237, pl. 8, figs. 13-19.

1976 Numofallotia apula Luperto Sinni – Luperto Sinni, pl. 48, figs. 4-5.

1976 Numofallotia apula Luperto Sinni – Charvet et al., pl. 7, figs. 6, 12.

1978 Numofallotia apula Luperto Sinni – Luperto Sinni & Ricchetti, pl. 45, figs. 11-13.

1978 Nummofallotia apula Luperto Sinni – Radoičić, pl. 4, figs. 7-8.

1979 Murgeina apula (Luperto Sinni) – Bilotte & Decrouez, p. 38, pl. 1, figs. 3-8 (synonymy).

1980 Nummofallotia apula Luperto Sinni – Fleury, pl. 3, fig. 6.

1981 Nummofallotia apula Luperto Sinni – Bismuth et al., pl. 4, figs. 6-8.

1982 Nummofallotia apula Luperto Sinni – Mouty & Saint-Marc, pl. 3, fig. 5.

1985 „ Nonion “ sp. – Bilotte, pl. 11, figs. 4-6.

1985 Numofallotia apula Luperto Sinni – Luperto Sinni, p. 100, pl. 48.

1988 Nummofallotia apula Luperto Sinni – Gušić & Jelaska, pl. 14, fig. 7.

1991 Nummofallotia apula Luperto Sinni – Schlagintweit & Weidich, pl. 1, fig. 6.

1992 Murgeina apula (Luperto Sinni) – Schlagintweit, p. 330, pl. 1, figs. 1–3 (synonymy).

1992 Nummofallotia apula Luperto Sinni – Mavrikas, pl. 1, fig. 28.

1994 Nonion senonicus (Perebaskine) – Ramírez del Pozo & Martín-Chivelet, pl. 1, fig. 4.

1994 Murgeina apula (Luperto-Sinni) – Chiocchini et al., pl. 22, figs. 9–13.

?1999 Nummofallotia cenomana sp. – Luperto Sinni, p. 2, fig. 1, pl. 1, figs. 1-9, pl. 1, figs. 9-11 as Nummofallotia apula .

2001 Murgeina apula (Luperto Sinni) – Cvetko Tešović et al., fig. 9B-E.

2002 Nummofallotia sp. – Bauer et al., pl. 3, fig. 12.

2003 Murgeina apula Luperto Sinni – Polavder, fig. 4.3.

2003 Murgeina apula (Luperto Sinni) – Aguilera-Franco, pl. 1, fig. i3.

2004 Murgeina apula (Luperto Sinni) – Bravi et al., fig. 13h (synonymy).

2006 Murgeina apula (Luperto Sinni) – Perugini, p. 71, pl. 2.

2010 Nummofallotia apula Luperto Sinni – Cavin et al., Fig. 9i-j.

2014 Nummofallotia apula Luperto Sinni – Afghah et al., fig. 11G.

2017 Murgeina apula – Jamalpour et al., pl. 2, fig. e.

2019 Murgeina apula – Kiarostami et al., pl. 1, fig. m.

2021 Murgeina apula – Dousti Mohajer et al., fig. 9a.

Description: Test lenticular, planispirally-involute coiled in up to three whorls, biumbonate with angular periphery and umbonal plug of hyaline and fibrous calcite. Proloculus almost spherical and enveloped by a wall differentiated into a thin microgranular inner and thick radial-calcitic outer layer. In axial, sections, the outer layer almost completely surrounds the proloculus ( Fig. 6b, i ). The chambers of elongate quadrangular shape gradually increase in size as added. In axial sections, the last whorl attains a width, about double the one observed in the penultimate whorl. The foramina are single, interiomarginal and in equatorial sections some kind of a short tooth-plate is occasionally observable at the distal end of the septum ( Figs. 6 r-s, 7d). The wall and the septa are bilamellar with a dark microgranular (finely agglutinated?) inner and hyaline fibrous-calcitic outer layer.

Dimensions: The dimensions of the specimens from the Cenomanian Sarvak Formation of Iran are summarized in Table 1 and compared with the data from Luperto Sinni (1968) from the ‘Senonian’ Altamura Limestone of S-Italy. For other data on dimensions of M. apula in the literature see Schlagintweit (1992), Cvetko Tešović et al., 2001, and Perugini (2006).

Remarks: Not mentioned previously ( Luperto Sinni 1968, 1985, 1999; Perugini, 2006), some kind of a short tooth plate may be present preferentially in the latest whorl(s) of adult specimens ( Fig. 6 r-s). It is also discernible in the good quality equatorial section provided by Saint-Marc (1974, pl. 8, fig. 16), that also shows 14 chambers in the last whorl (see discussion in Comparisons). Luperto Sinni (1985, p. 100) mentioned a ‘courte canal flexostyle’, that in some alveolinid taxa represents a tubular extension following the proloculus ( Hottinger, 2006). Although not explicitly highlighted in any image by Luperto Sinni (1985), it might well belong to recrystallized neanic chambers or a shallow tangential sectioning of the umbo (e.g., Fig. 6q, s ).

Comparisons: With respect to the dimensions, there are no differences between the Cenomanian and the later Cretaceous (i.e., Campanian) forms of Murgeina apula ( Tab. 1 ). As a possible difference, both Luperto Sinni (1968) and Perugini (2006) noted 16 to 20 chambers in the final whorl of Campanian forms which differs from the Cenomanian forms studied herein with a maximum number of 15. However, the only illustrated specimen in Luperto Sinni (1968, pl. 3, fig. 6) that allows the chambers in the last whorl to be counted shows a number of 14, and thus overlapping with the data from the Cenomanian forms. In 1999, Luperto Sinni described another species as Nummofallotia cenomana from the Cenomanian of the same area (Murge, south Italy) displaying 14 to 16 chambers in the last whorl. In our opinion, this minor difference (that has not been further discussed by Luperto Sinni, 1999) is not suitable as a criterion for species discrimination. It can reasonably also be considered as an intraspecific variation in time. As her main criterion for discrimination of ‘ N.’ apula and ‘ N.’ cenomana, Luperto Sinni (1999, p. 2) stressed the thinning of the outer hyaline-calcareous layer towards the test periphery (up to its complete absence in this area) in the former. In ‘ N.’ cenomana instead it is said to be always present. In fact, the specimens of Murgeina apula from the Campanian of Croatia show that this feature is variable with only a thin ( Fig. 7j ) or thicker outer layer ( Fig. 7a ) and therefore again not suitable for species discrimination. It is worth mentioning, that this observation has also been made by Perugini (2006) studying a comparably rich assemblage from the Altamura Limestone of the Murge area. The third characteristic to be mentioned refers to the test dimensions. For the holotype of ‘ N.’ cenomana, Luperto Sinni (1999, p. 2) indicated 0.09 mm for the thickness and 0.05 mm for the diameter. The indicated values are considered as seemingly incorrect, and much too small. If correct, then it would be rather curious that Luperto Sinni (1999) did not highlight it in the discussion on species differences. Summarizing, there appear to be no characters that would justifiably separate a Cenomanian (= ‘ N.’ cenomana ) and a post-Cenomanian (= ‘ N.’ apula ) species, resulting in an assumed synonymy of both with Murgeina apula having priority.

Biostratigraphy: Luperto Sinni (1968, p. 96) assigned the strata containing ‘ N.’ apula to the ‘Upper Senonian’, mostly to the Maastrichtian. Among the species associated with M. apula, Luperto Sinni (1968, p. 95) indicated also Accordiella conica Farinacci , that has a middle Coniacian to early middle Campanian age according to new results from southern Italy published by Frijia et al., (2015). Also, the occurrence of orbitolinids in the type strata of M. apula (fide Luperto Sinni, 1968) can be considered as further evidence for a Campanian age (see Schlagintweit, 2021). M. apula has been reported by Cvetko Tešović et al. (2001) from the (early) Maastrichtian of the Sumartin Formation of Croatia that should correspond to its youngest record. Summarizing, M. apula represents a methusalem taxon with a recorded early Cenomanian–(early) Maastrichtian range, almost comparable to another simple structured small presumably rstrategist taxon, Moncharmontia apenninica (De Castro) ( Table 2 ). For both taxa there is a gap in the record following the Cenomanian–Turonian boundary extinction (e.g., Parente et al., 2008). While M. apenninica is reported from upper Turonian strata, M. apula re-appears later in the early Coniacian ( Chiocchini et al., 2012, fig. 10).

Figures

Fig. 3 Lithological log of the Maymand section with distribution of larger benthic foraminifera (including Murgeina apula Luperto-Sinni) (after Schlagintweit & Yazdi-Moghadam, 2020). a Nezzazata gr. gyra-conica (Smout), b Nezzazata simplex Omara, c Murgeina apula (Luperto-Sinni), d Orbitolina gr. concava Orbigny, e Rajkanella hottingerinaformis Schlagintweit & Rigaud, f Biconcava bentori Hamaoui & Saint-Marc, g Praealveolina simplex Reichel, h Chrysalidina gradata Orbigny, i Cisalveolina fraasi (Gümbel), j Persiconus sarvaki Yazdi-Moghadam & Schlagintweit.

Fig. 5 Possible post-Triassic fusulinanids Protopeneroplis striata Weynschenk (a-c), Upper Jurassic of Romania and Murgeina apula (Luperto Sinni), Upper Cretaceous (Campanian) of Croatia (d). a Axial section. Note the irregular coiling, the alternating dark and bright layers in the umbo, and the presence of an outer hyaline-calcitic layer (arrow). b-c Equatorial sections. Note the double-layered septum (s) and wall (arrow). d Slightly oblique axial section. Note the alternating dark and bright layers in the umbo (compare to P. striata in a).

Fig. 6 Murgeina apula (Luperto Sinni) from the Cenomanian Sarvak Formation of SW Iran. a-b, d, f-i, l, n, s, t Axial sections, partly slightly oblique. Note the double-layered septa in s. c, j, k, m, r, v. Oblique sections. e Slightly oblique subaxial section. q, s, u Equatorial sections. Note the double-layered septa in q. Abbreviations: fo = foramen, pr = proloculus, se = septum, t.pl. = tooth plate, um = umbo. Thin sections: DB 14550 (a), BF 86 (b-c), BF 37 (d, v), BF 56 (e, g), BF 70 (f), BF 48 (h), BF 33 (i-l, p, s), BF 82 (m), BF 40 (n), BF 37 (o, q, u), BF 46 (r), BF 56 (t).

Fig. 7 Murgeina apula (Luperto Sinni) from the early-middle Campanian Pučišća Formation of the Island of Brač. a-b, f, h, j Axial sections. c-e, g Oblique sections. Note the presence of some kind of tooth plate in d (t. p.). i) Subaxial section.