Dasykothon leptomiscus gen. et sp. nov., a fossil 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

A new fossil angiosperm, Dasykothon leptomiscus, is described from mid-Cretaceous amber deposits in the Hukawng Valley of northwestern Myanmar (Burma). The flower is post-anthesis except for one stamen that retains its pollen. The perianth is slightly irregular and composed of 5 ovate or lance-linear, erect or incurved sepals. The ca. 12 stamens have slender, elongate filaments and dorsifixed, bithecal, longitudinally dehiscent anthers. The superior ovary bears 2 long, curved styles. Germinating pollen grains observed on the stigmas are monoporate and have the peculiar feature of a grooved ridge encircling the grain from pole to pole. This structure is hypothesized to be an evolutionary elaboration of the meridionally syncolpate sulcus found in some members of the Atherospermataceae. The generalized floral morphology of the fossil prevents ready taxonomic assignment to a modern family.

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Published
2020-07-15
How to Cite
Poinar, Jr., G. O., & Chambers, K. L. (2020). Dasykothon leptomiscus gen. et sp. nov., a fossil flower of possible Lauralean affinity from Myanmar amber. Journal of the Botanical Research Institute of Texas, 14(1), 65-71. https://doi.org/10.17348/jbrit.v14.i1.897

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