Dispariflora robertae gen. et sp. nov., a mid-Cretaceous flower of possible Lauralean affinity from Myanmar amber

  • George O. Poinar, Jr. Department of Integrative Biology, Oregon State University
  • Kenton L. Chambers Department of Botany and Plant Pathology, Oregon State University

Abstract

Three flowers of a fossil angiosperm preserved in amber from Myanmar (Burma) are described as the new genus and species Dispariflora robertae. Although joined in a single cymose inflorescence, the flowers are variable in size and, in addition, they possess an unusual perianth in which 1 sepal is much enlarged and leaf-like, while the remaining 4 are smaller and unequal. The flowers each have 1 superior pistil with a peculiarly plumose and bristly ovary. The number of stamens is uncertain because most were lost before floral preservation, but scars on the receptacle suggest that at least 15 were present. The bithecal anthers open by longitudinal slits and basal glands may have been present on the filaments. Taken as a whole, the floral features that characterize Dispariflora suggest an affinity with members of Laurales, especially several Southern Hemisphere families allied with the Monimiaceae.

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Published
2019-07-23
How to Cite
Poinar, Jr., G. O., & Chambers, K. L. (2019). Dispariflora robertae gen. et sp. nov., a mid-Cretaceous flower of possible Lauralean affinity from Myanmar amber. Journal of the Botanical Research Institute of Texas, 13(1), 173-183. https://doi.org/10.17348/jbrit.v13.i1.839

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