Endobeuthos paleosum gen. et sp. nov., fossil flowers of uncertain affinity from mid-Cretaceous 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


Endobeuthos paleosum gen. et sp. nov. is based on 6 flowers preserved together in a single block of mid-Cretaceous amber from Myanmar (Burma). The calyx is composed of ca. 50+ small, helically arranged sepals. The corolla consists of 5 imbricate petals forming a sheath-like structure that is usually concealed within the calyx. The petal tips are often spreading and exserted from the calyx. There are numerous stamens, each of which consists of a filament and an enlarged anther connective with a single lateral, bisporangiate theca. Dehiscence is extrorse. The tips of 3 or 4 styles are visible, indicating that the flowers are bisexual. The fossils possess unique features that prevent assignment to any modern family. However, the numerous sepals and stamens and a thickened anther connective may suggest an association of E. paleosum with the family Dilleniaceae.


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How to Cite
Poinar, Jr., G. O., & Chambers, K. L. (2018). Endobeuthos paleosum gen. et sp. nov., fossil flowers of uncertain affinity from mid-Cretaceous Myanmar amber. Journal of the Botanical Research Institute of Texas, 12(1), 133-139. https://doi.org/10.17348/jbrit.v12.i1.923

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