Thymolepis toxandra gen. et sp. nov., a mid-Cretaceous fossil flower with horseshoe-shaped anthers

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

Abstract

The fossil flower described here as Thymolepis toxandra is from amber deposits in Myanmar which have been dated as ca. 100 Ma. The peri-anth consists of 12 tepals of varying size and shape, arranged in decussate pairs at the summit of an obconic floral cup. The epidermis of some of the tepals is densely papillate-secretory. The flower is bisexual, the androecium consisting of 2 stamens whose anthers are bisporangiate, hippocrepiform, and densely hirsute. The gynoecium is visible only as a bilobed stigma or as the tips of two postgenitally fused styles, the re-mainder of the pistil(s) being hidden by the perianth and floral cup. It is suggested that the fossil may be an early representative of family Monimiaceae.

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Published
2020-07-15
How to Cite
Chambers, K. L., & Poinar, Jr., G. O. (2020). Thymolepis toxandra gen. et sp. nov., a mid-Cretaceous fossil flower with horseshoe-shaped anthers. Journal of the Botanical Research Institute of Texas, 14(1), 57-64. https://doi.org/10.17348/jbrit.v14.i1.896

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