Bulbobaculites problematicus ( Neagu, 1962 )

Besen, Richard M., Struck, Ulrich & Seibertz, Ekbert, 2021, Albian to Turonian agglutinated foraminiferal assemblages of the Lower Saxony Cretaceous sub-basins - implications for sequence stratigraphy and paleoenvironmental interpretation, Fossil Record 24 (2), pp. 395-441 : 413-414

Bulbobaculites problematicus ( Neagu, 1962)

Fig. 7i

1962. Ammobaculites agglutinans problematicus Neagu , p. 61, pl. 2, figs. 22–24.

1970. Ammobaculites problematicus (Neagu) ; Neagu, p. 39, pl. 6, figs. 1–5.

1990. Haplophragmium problematicum (Neagu) ; Kuhnt, p. 312, pl. 4, figs. 3–9.

1990. Bulbobaculites problematicus (Neagu) ; Kuhnt and Kaminski, p. 465, text fig. 5, 5A.

2011. Bulbobaculites problematicus (Neagu) ; Kaminski et al., p. 92, pl. 5, figs. 5–7.

Material

A total of 3 specimens from the Baddeckenstedt section, 746 specimens from the Söhlde section, 270 specimens from the Wunstorf Wu2010/1 core, 22 specimens from the Wunstorf Wu2010/3 core, and 969 specimens from the Wunstorf Wu2010/4 core.

Remarks

Bulbobaculites problematicus has a wide range of morphological variety ( Kuhnt and Kaminski, 1990). It can be used in the Atlantic realm as a post-Cenomanian marker but already appears in the Cenomanian in the Tethys realm of the Carpathians ( Neagu, 1962; Huss, 1966; Geroch and Novak, 1984). Tethyan post-Cenomanian assemblages with increased B. problematicus are documented by B ˛ak (2000). In Wunstorf, this species is noted already in the Albian.

Occurrence

Very abundant at the Cenomanian–Turonian boundary interval, very abundant to common in the Turonian at Söhlde, common to rare in the Cenomanian at Wunstorf, and very rare at Baddeckenstedt.

Figures

Figure 7. Late Albian to Turonian agglutinated foraminifers from the Lower Saxonian Cretaceous; scale bars are 100 µm. (a) Reophax subfusiformis, Wunstorf Wu2010/1, 54.00m. (b) Pseudonodosinella nodulosa, Wunstorf Wu2010/4, 48.20m. (c) Pseudonodosinella parvula, Wunstorf Wu2010/4, 48.20 m. (d) Pseudonodosinella troyeri, Baddeckenstedt section, 39.00 m. (e) Haplophragmoides suborbicularis, Wunstorf Wu2010/3, 70.50 m. (f) Haplophragmoides walteri, Wunstorf Wu2010/4, 48.95 m. (g) Ammobaculites agglutinans, Söhlde section, 31.00 m. (h) Ammobaculites wenonahae, Wunstorf Wu2010/1, 19.05m. (i) Bulbobaculites problematicus, Wunstorf Wu2010/1, 24.75m. (j) Spiroplectammina navarroana, Wunstorf Wu2010/4, 48.20 m. (k) Spiroplectinella cretosa, Baddeckenstedt section, 2.00 m. (l) Bicazammina lagenaria, Söhlde section, 24.00m. (m) Parvigenerina sp. 3, Wunstorf Wu2010/4, 48.95 m. (n) Eobigenerina kuhnti, Söhlde section, 9.50m. (o) Eobigenerina variabilis, Söhlde section, 1.50 m. (p) Rectogerochammina eugubina, Wunstorf Wu2010/4, 48.95m. (q) Gerochammina stanislawi, Wunstorf Wu2010/4, 53.15 m. (r) Plectina cenomana, Wunstorf Wu2010/3, 45.00 m. (s) Plectina mariae, Wunstorf Wu2010/3, 84.00m.