Nannotax3 - ntax_mesozoic - Eoconusphaera zlambachensis

Distinguishing features:
Parent taxon (Eoconusphaera): Tall tapering nannoliths with steeply sloping rim and central area filled with a mass of radially arranged elements. LM image shows relatively uniformily birefringent core with axial extinction line.
This taxon: Tall tapering nannoliths with steeply sloping rim and central area filled with a mass of radially arranged elements. Most commonly seen in side view. LM image shows relatively uniformily birefringent core with axial extinction line.

Citation: Eoconusphaera zlambachensis (Moshkovitz, 1982) Kristan-Tollmann, 1988

Basionym: Conusphaera zlambachensis Moshkovitz, 1982

Synonyms:

Eoconusphaera tollmanniae Jafar 1983 [according to Kristan-Tollmann, 1988, Bralower et al. 1991]
Conusphaera tollmanniae (Jafar 1983) Janofske 1987

The outer rim is formed of vertical laths arranged tangential to the rim, without overlap or imbrication and with directly butting edges. The core is formed of steeply dipping laths arranged radially and with clockwise imbrication. Posch & Stradner (1987) suggest that the structure of the core consists of about 8 segments each of which is formed of a separate set of steeply dipping laths.

Geological Range:
Notes: Gardin et al. (2012) record FO near base of the Rhaetian.
Last occurrence (top): within NT2b subzone (201.1-218.91Ma, top in Hettangian stage). Data source: Bown 1998b
First occurrence (base): within NT2b subzone (201.1-218.91Ma, base in Norian stage). Data source: Bown 1998b

References:

Bown, P. R. & Cooper, M. K. E. (1989a). Conical nannofossils in the Mesozoic. In, Crux, J. A. & van Heck, S. E. (eds) Nannofossils and their applications: Proceedings of the 2nd INA Conference, London 1987. British Micropalaeontological Society Publication Series . 98-106. gs

Bown, P. R. & Young, J. R. (1997). Mesozoic calcareous nannoplankton classification. Journal of Nannoplankton Research. 19(1): 21-36. gs

Bown, P. R. (1987a). Taxonomy, evolution, and biostratigraphy of Late Triassic-Early Jurassic calcareous nannofossils. Special Papers in Palaeontology. 38: 1-118. gs

Bown, P. R. (1998b). Triassic. In, Bown, P. R. (ed.) Calcareous Nannofossil Biostratigraphy. British Micropalaeontological Society Publication Series . 29-33. gs

Bralower, T. J., Bown, P. R. & Siesser, W. (1991). Significance of Upper Triassic nannofossils from the Southern Hemisphere (ODP Leg 122, Wombat Plateau, NW Australia). Marine Micropaleontology. 17: 119-154. gs

Demangel, I., Howe, R., Gardin, S. & Richoz, S. (2021). Eoconusphaera hallstattensis sp. nov. and a review of the Rhaetian genus Eoconusphaera. Journal of Nannoplankton Research. 39(1): 77-87. gs O

Gardin, S., Krystyn, L., Richoz, S., Bartolini, A. & Galbrun, B. (2012). Where and when the earliest coccolithophores? Lethaia. 45: 507-523. gs

Jafar, A. S. (1983). Significance of Late Triassic calcareous nannoplankton from Austria and Southern Germany. Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen. 166: 218-259. gs

Janofske, D. (1987). Kalkige Nannofossilien aus der Ober-Trias (Rhat) der Nordlichen Kalkalpen. Berliner Geowissenschaftliche Abhandlungen. 86: 45-67. gs

Kristan-Tollmann, E. (1988). Coccolithen aus den Älteren Allgäuschichten (Alpiner Lias, Sinemur) von Timor, Indonesien. Geologisch-Paläontologische Mitteilungen Innsbruck. 15: 71-83. gs

Moshkovitz, S. (1982). On the findings of a new calcareous nannofossil (Conusphaera zlambachensis) and other calcareous organisms in the Upper Triassic sediments of Austria. Eclogae Geologicae Helvetiae. 75: 611-619. gs

Posch, F. & Stradner, H. (1987). Report on Triassic nannoliths from Austria. Abhandlungen der Geologischen Bundesanstalt. 39: 231-237. gs

Eoconusphaera zlambachensis

References:

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