Catalog - Chiloguembelitria hofkeri

This page provides data from the catalog of type descriptions. The catalog is sorted alphabetically. Use the current identification link to go back to the main database.

Other pages this level: C. biseriata, C. danica, C. hofkeri, C. trilobata

Chiloguembelitria hofkeri

Citation: Chiloguembelitria hofkeri Arenillas et al. 2017

Type specimens: Fig. 5(c); Fig. 12(h); Fig. 13(a)e(d); Holotype MPZ 2016/108 (Fig. 13(a)). Paratype MPZ 2016/109 (Fig. 13(b)). MPZ 2016/110 (Fig. 13(c)). Paratype MPZ 2016/111 (Fig. 13(d)). Type-specimens deposited in the Museo de Ciencias Naturales de la Universidad de Zaragoza (Aragon Government, Spain).

Type sample (& lithostrat): 7.50 m above the Cretaceous/Paleogene boundary of the El Kef section (sample KF19.50)

Type age (chronostrat): lower part of Zone P1a, or the middle part of the Eoglobigerina trivialis Subzone (Parasubbotina pseudobulloides Zone), lower Danian

Type locality: El Kef section, El Haria Formation, Tunisia.

Type repository: Zaragosa; Museo de Ciencias Naturales de la Universidad de Zaragoza

Test elongated, subconical, high-spired. Triserial arrangement, often slightly twisted, with 11-14 subspherical chambers distributed in 3.5-4.5 spiral whorls, with low rate of chamber enlargement. Outline subtriangular, lobate, with incised sutures. Aperture interiomarginal, umbilical-extraumbilical to extraumbilical, rounded or elongate, generally asymmetrical, with an imperforate lip. Wall surface microperforate, pustulate to rugose, with isolated, decentered pore-mounds, perforate and/or imperforate rugosities, and blunt pustules (papilla-type).

Adult size range 120-180 mm in height.

Species dedicated to Jan Hofker for the discovery and definition of the Danian genus Chiloguembelitria.

1978 Chiloguembelitria danica Hofker, p. 60, pl. 4, Fig. 14.
1987 Guembelitria danica (Hofker); Loeblich and Tappan, p. 452, part, pl. 484, Fig. 8.
non 1993 Guembelitria danica (Hofker); MacLeod, pl. 3, Figs. 1 and 5.
2007 Guembelitria danica (Hofker); Arenillas et al., p. 38, Figs. 13.14e17.

Remarks. It differs from Chg. danica in having a higher-spired test. The gross morphology of Chg. hofkeri sp. nov. is similar to the original holotype of Chg. danica illustrated by Hofker (1978). Nevertheless, because this holotype was invalidated (depository not given by the author), the name "danica" should be used to refer to Chiloguembelitria specimens with a medium-spired test, such as the neotype designated by Jenkins et al. (1998). The difference in spire height of Chg. hofkeri sp. nov. from Chg. danica and Chg. trilobata sp. nov. is similar to that of Guembelitria dammula from G. cretacea and G. blowi (Arz et al., 2010). These two triplets of species differ from each other in the wall texture and the position and shape of the aperture. Danian specimens of Chg. hofkeri sp. nov. have commonly been attributed to G. cretacea (MacLeod, 1993; Olsson et al., 1999; Arenillas et al., 2000a, 2000b), but Arenillas et al. (2007) and Arz et al. (2010) have already pointed out the possible existence in the early Danian of a pseudocryptic species similar to Guembelitria spp. but with a rugose wall.

Occurrence. Lowermost Danian, from the upper part of Zone P0 to the middle part of Zone P1b of Berggren and Pearson (2005), i.e. from the upper part of the Hedbergella holmdelensis Subzone (Guembelitria cretacea Zone) to the middle part of the S. triloculinoides Subzone (Parasubbotina pseudobulloides Zone) of Arenillas et al. (2004). It is very frequent in the Eoglobigerina trivialis Subzone (Parasubbotina pseudobulloides Zone), i.e. in P1a (Fig. 1).

References:

Arenillas, I., Arz, J. A. & Gilabert, V. (2017). Revalidation of the genus Chiloguembelitria Hofker: Implications for the evolution of early Danian planktonic foraminifera. Journal of African Earth Sciences. 134: 435-456. gs

CATALOG OF ORIGINAL DESCRIPTIONS: Chiloguembelitria hofkeri Arenillas et al. 2017

Chiloguembelitria hofkeri

References:

Add Comment

Comments