Bramkampella arabica Redmond, 1964

Pleş, George, Bucur, Ioan I. & Păcurariu, Adriana, 2015, Foraminiferal Assemblages And Facies Associations In The Upper Jurassic Carbonates From Ardeu Unit (Metaliferi Mountains, Romania), Acta Palaeontologica Romaniae 11 (2), pp. 43-57 : 48-49

Bramkampella arabica Redmond, 1964

( Fig. 3 a-c)

1964 – Bramkampella arabica – Redmond, p. 409-414, pl. 1, figs. 26-29; pl. 2, figs. 19-20.

1988 – Bramkampella arabica – Loeblich & Tappan., p. 101-102, pl. 100, figs. 14-18.

1991 – Bramkampella arabica – Banner & Whittaker, p. 45, pl. 2, figs. 1-7.

1997 – Bramkampella arabica – Gorbachik & Mohamad, p. 347, pl. 1, figs. 8, 9, 11.

2005a – Bramkampella arabica – Bucur & Sasaran, pl. 2, figs. 6, 7.

Description: The test is subconical with a fine-grained imperforate agglutinated wall. In early ontogenetic stages, the test is planspirally-enrolled, involute. In the adult stage, the test begins to uncoil, finally becoming rectilinear, uniserial, up to 2.21 mm in lenght. In transversal section the test is circular in shape with a diameter size between 1.1 – 1.56 mm. The chambers are short and flattened, separated by strongly embowed septa. Beams and rafters are displayed as an interseptal alveolar network (septulae). The spetulae are elongated and radially developed inward up to the central part of the test. The aperture is terminal, multiple, represented as large pores on the central part of the septal surface.

Remarks: In our samples, Bramkampella arabica is frequently associated with the species described before ( L. mirabilis , P. caelinensis and E. praekelleri ). Several similarities with other cyclamminids, especially with Rectocyclammina chouberti Hottinger can be noticed sometimes. They are restricted mainly to the internal morphology of the species. Even so, the multiple aperture, the presence of interseptal pillars or the highly arched septa, clearly differentiate Bramkampella arabica from Rectocyclammina chouberti ( Gorbachik & Mohamad, 1997) .

Stratigraphic range: Bramkampella arabica was firstly described from Upper Jurassic-basal Cretaceous deposits from Arabia by Redmond (1964). Several lowermost Cretaceous (Berriasian-Valanginian) records of the species were documented by Gorbachik & Mohamad (1997) and Nouajim Clark & Boudagher-Fadel (2001). Due to these occurrences, mainly in lowermost Cretaceous carbonates, B. arabica was considered to be an index marker for the Berriasian-?Valanginian interval. However, Bucur & Săsăran (2005a) identified this species, besides the lowermost Cretaceous deposits, in Kimmeridgian-upper Tithonian limestones from Trascău Mountains. In the samples from Ardeu Unit, B. arabica is also found in association with typical Upper Jurasic foraminifera ( L. mirabilis or P. caelinensis ). Summarizing, the stratigraphic position of Bramkampella arabica is Kimmeridgian-?lower Valanginian.

Figures

Fig. 3 Upper Jurassic foraminifers from the Ardeu Unit. a-c Bramkampella arabica Redmond (a - Sample 65, b - Sample 172, c - Sample 146). d Undetermined lituolid (Sample 41). e Kaminskia-type foraminifer with fine canaliculated wall (Sample 66). f-h Everticyclammina praekelleri Banner & Highton (Sample 65). i Alveosepta jaccardi (Schrodt) (Sample 49). j-l Ammobaculites sp. (j - Sample 65, k - Sample 110, l - Sample 95). m-n Charentia evoluta (Gorbachik) (m - Sample 32, n - Sample 45). o-p Protopeneroplis striata Weynschenk (o - Sample 153, p - Sample 212).