Watznaueria diaphanae
Set number: 3202
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10µm
Watznaueria diaphanae IWorsley, 1971
Coccolithites supracretaceus Reinhardt, 1965. Under the ICN, any species name originally published in association with a provisional genus is not validly published (ICN Art. 35.1) and therefore has no standing under the ICN.
Watznaueria supracretacea (Reinhardt 1965) Wise & Wind 1977, Invalid according to ICN Art. 35.1.
Small- to medium-sized (3.0–7.0 µm), elliptical species of Watznaueria, characterised by a distal shield that is larger than the proximal shield and a narrow, indistinct central area. The central area and its features, consisting of two small depressions located at opposite ends along the long axis and connected by a suture, are only resolvable under phase-contrast illumination.
In plan view under cross-polarised light, the shields display white interference colours that decrease in intensity towards the periphery, where only the distal shield is present, and show parallel extinction lines and length-fast (–) elongation. The central area is not resolvable under cross-polarised light. The extinction angles are 0° in the shields.
Watznaueria diaphanae differs from Watznaueria bayackii in its optical properties: Watznaueria diaphanae displays parallel extinction (0°), whereas Watznaueria bayackii exhibits inclined extinction with extinction angles of about 65–75°.
Watznaueria diaphanae is further distinguished from Watznaueria sp.1 by the nature of the central area. In Watznaueria diaphanae, the central area is not resolvable under cross-polarised light, whereas in Watznaueria sp.1 the narrow, elongate central area is visible and exhibits dimmer interference colours than the shields.
Reinhardt, P. 1965. Neue Familien für fossile Kalkflagellaten (Coccolithophoriden, Coccolithineen). Monatsberichte der Deutschen Akademie der Wissenschaften zu Berlin. 7: 30-40.
Worsley, T. R., 1971. Calcareous nannofossil zonation of Upper Jurassic and Lower Cretaceous sediments from the Western Atlantic. In: Farinacci, A. (ed.), Proceedings of the Second Planktonic Conference Roma 1970. Edizioni Tecnoscienza, Rome vol. 2, pp. 1301-1321.
Wise, S. W. & Wind, F. H. 1977. Mesozoic and Cenozoic calcareous nannofossils recovered by DSDP Leg 36 drilling on the Falkland Plateau, south-west Atlantic sector of the Southern Ocean. Initial Reports of the Deep Sea Drilling Project. 36: 269-491.
Holotype
Watznaueria diaphanae
Worsley, 1971
Berriasian - Valanginian
JOIDES, DSDP, Leg 1, hole 4, Caribbean Sea.