Sphenobaiera

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Sphenobaiera
Temporal range: Late Cretaceous
Scientific classification
Kingdom: Plantae
Division: Ginkgophyta
Class: Ginkgoopsida
Order: Ginkgoales
Family: incertae familiae
Genus: Sphenobaiera
Florin emend Harris & Millington[1]

Sphenobaiera is a plant that lived in the Late Cretaceous period. The genus Sphenobaiera is used for plants with wedge-shaped leaves that can be distinguished from Ginkgo, Ginkgoites and Baiera by the lack of a petiole.[1] It went extinct about 72.6 million years ago. The family to which this genus belongs has not been conclusively established; an affinity with the Karkeniaceae has been suggested on morphological grounds.[2]

Locations[edit]

Sphenobaiera ikorfatensis (Seward) Florin f. papillata Samylina has been found in Lower Cretaceous formations of Western Greenland, the Upper Jurassic of the Asiatic USSR, and the basal rock unit of the Lakota formation of the Black Hills, which Fontaine considered to be of Lower Cretaceous age. It is a ginkgophyte.[3]

In Paleorrota geopark in Brazil. Upper Triassic period, the Santa Maria Formation.[4]

References[edit]

  1. ^ a b Susannah J. Lydon, Joan Watson & Nicola A. Harrison (2003). "The lectotype of Sphenobaiera ikorfatensis (Seward) Florin, a ginkgophyte from the Lower Cretaceous of western Greenland". Palaeontology 46 (2): 413–421. doi:10.1111/1475-4983.00304. 
  2. ^ Wang, Yongdong; et al. (April 2005). "Cuticular Anatomy of Sphenobaiera Huangii (Ginkgoales) from the Lower Jurassic of Hubei, China" (PDF embedded in HTML). American Journal of Botany 92 (4): 709–721. doi:10.3732/ajb.92.4.709. Retrieved 7 June 2011. 
  3. ^ Elizabeth J. Cahoon (1960). "Sphenobaiera ikorfatensis f. papillata from the Lakota Formation of the Black Hills". Bulletin of the Torrey Botanical Club 87 (4): 247–257. JSTOR 2482869. 
  4. ^ Passo das Tropas, Santa Maria, RS. Marco bioestratigráfico triássico na evolução paleoflorística do Gondwana na Bacia do Paraná