Tropidogyne lobodisca sp. nov., a third species of the genus 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

Abstract

The fossil flower described here is the third species of Tropidogyne to have been collected from mid-Cretaceous amber deposits in the Hukawng Valley of northwestern Myanmar. The flower of Tropidogyne lobodisca differs from the 2 previously described species, T. pikei and T. pentaptera, in lacking stamens and having a 5-lobed nectar disc covering the apex of the ovary. Its 2 slender, curved, attenuate styles are like those of T. pentaptera in being stigmatic along the adaxial surface. The new species has 5 spreading, reticulately-veined sepals, a generic character of Tropidogyne. An unusual, probably teratological, feature is the presence of 2 sepal-like staminodes on one side of the flower, inserted at the base of the nectar disc where stamens would otherwise be found. The inferior portion of the pistil is obconic, with 5 distinct veins that connect to the mid-nerves of the sepals.

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Published
2019-10-31
How to Cite
Poinar, Jr., G. O., & Chambers, K. L. (2019). Tropidogyne lobodisca sp. nov., a third species of the genus from mid-Cretaceous Myanmar amber. Journal of the Botanical Research Institute of Texas, 13(2), 461-466. https://doi.org/10.17348/jbrit.v13.i2.798

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