Strombothelya gen. nov., a fossil angiosperm with two species in mid-Cretaceous Myanmar amber
Strombothelya, a new genus of fossil angiosperms from Myanmar amber deposits, is represented by 2 flowers that are here described as separate species. Flowers of Strombothelya have 5 spreading, more or less distinctly veined sepals. Petals are absent. There are 10 inwardly arching stamens and a half-inferior ovary, whose broadly conic superior portion terminates in 1 or 3 stout, columnar, apically truncate styles. The superior portion has a papillate surface that was probably nectarifer-ous. The inferior portion of the ovary in both species is obconic and 5- or 10-ribbed. The fossils are comparable in certain respects to the genus Tropidogyne, described earlier from the same amber deposits. The 3 species of Tropidogyne have flowers with 5 or 10 stamens and 2 or 3 slender, curved, acutely-tipped styles. The inferior portion of the ovary is strongly 10-ribbed, while the superior portion is flat or cushion-shaped and bears a lobed nectar-disc. Strombothelya and Tropidogyne inhabited a Cretaceous araucarian rainforest, which may have been located in the Southern Hemisphere continent of Gondwana.
Barnes, R.W. & R.S. Hill. 1999. Ceratopetalum fruits from Australian Cainozoic sediments and their significance for petal evolution in the genus. Austral. Syst. Bot. 12:635–645.
Barnes, R.W., R.S. Hill, & J.C. Bradford. 2001. The history of Cunoniaceae in Australia from macrofossil evidence. Austral. J. Bot. 49:301–320.
Bradford, J.C., H.C.F. Hopkins, & R.W. Barnes. 2004. Cunoniaceae. In: K. Kubitzki, ed. The families and genera of vascular plants. Springer-Verlag, Berlin, Germany. 6:91–111.
Chambers, K.L., G.O. Poinar, Jr., & R. Buckley. 2010. Tropidogyne, a new genus of Early Cretaceous eudicots (Angiospermae) from Burmese amber. Novon 20:23–29.
Cohen, K.M., S. Finney, & P.L. Gibbard. 2013. International Chronostratigraphic Chart. International Commission on Stratigraphy.
Cruickshank, R.D. & K. Ko. 2003. Geology of an amber locality in the Hukawng Valley, northern Myanmar. J. Asian Earth Sci. 21:441–455.
Dickison, W.C. 1989. Comparison of primitive Rosidae and Hamamelidae. In: P.R. Crane & S. Blackmore, eds. Evolution, systematics, and fossil history of the Hamamelidae. Oxford Univ. Press, London. Syst. Assoc. Spec. Vol. 40(1):47–73.
Engler, A. 1930. Cunoniaceae. In: A. Engler & K. Prantl, eds. Die natürlichen Pflanzenfamilien, ed. 2. W. Engelemann, Leipzig, Germany. 18a:229–262.
Gandolfo, M.A. & E.J. Hermsen. 2017. Ceratopetalum (Cunoniaceae) fruits of Australasian affinity from the early Eocene Laguna del Hunco flora, Patagonia, Argentina. Ann. Bot. 119:507–516.
Hall, R. 2012. Late Jurassic-Cenozoic reconstructions of the Indonesian region and the Indian Ocean. Tectonophysics 570–571:1–41.
Liu, Z-J., D. Huang, C. Cai, & X. Wang. 2018. The core eudicot boom registered in Myanmar amber. Scientific Reports 8:16765.
Metcalfe, I. 2013. Gondwana dispersion and Asian accretion: Tectonic and palaeogeographic evolution of eastern Tethys. J. Asian Earth Sci. 66:1–33.
Poinar, G.O., Jr. 2018a. Burmese amber: Evidence of Gondwanan origin and Cretaceous dispersion. Hist. Biol. 2018:1–6.
Poinar, G.O., Jr. 2018b. Mid-Cretaceous angiosperm flowers in Myanmar amber. In: B. Welch & M. Wilkerson, eds. Recent advances in plant research. Nova Science Publishers, New York, U.S.A. Pp. 187–218.
Poinar, G.O., Jr. & K.L. Chambers. 2017. Tropidogyne pentaptera sp. nov., a new mid-Cretaceous fossil angiosperm flower in Burmese amber. Palaeodiversity 10:135–140.
Poinar, G.O., Jr. & K.L. Chambers. 2018a. Endobeuthos paleosum gen. et sp. nov., fossil flowers of uncertain affinity from mid-Cretaceous Myanmar amber. J. Bot. Res. Inst. Texas 12:133–139.
Poinar, G.O., Jr. & K.L. Chambers. 2018b. Fossil flowers of Lachnociona camptostylus sp. nov., a second record for the genus in mid-Cretaceous Myanmar amber. J. Bot. Res. Inst. Texas 12:655–666.
Poinar, G.O., Jr. & K.L. Chambers. 2019a. Dispariflora robertae gen. et sp. nov., a mid-Cretaceous flower of possible Lauralean affinity from Myanmar amber. J. Bot. Res. Inst. Texas 13:173–183.
Poinar, G.O., Jr. & K.L. Chambers. 2019b. Tropidogyne lobodisca sp. nov., a third species of the genus from mid-Cretaceous Myanmar amber. J. Bot. Res. Inst. Texas 13:xxx-xxx.
Poinar, G.O., Jr. & K.L. Chambers. 2019c. Zygadelphus aetheus gen. et sp. nov., an unusual fossil flower from mid-Cretaceous Myanmar amber. J. Bot. Res. Inst. Texas 13:xxx-xxx.
Poinar, G.O., Jr., G.J.B. Lambert, & Y. Wu. 2007. Araucarian source of fossiliferous Burmese amber: Spectroscopic and anatomical evidence. J. Bot. Res. Inst. Texas 1:449–455.
Rozefelds, A.C. & R.W. Barnes. 2002. The systematic and biogeographical relationships of Ceratopetalum (Cunoniaceae) in Australia and New Zealand. Int. J. Pl. Sci. 163:651–673.
Shi, G., D.A. Grimaldi, G.E. Harlow, J. Wang, M. Yang, W. Lei, Q. Li, & X. Li. 2012. Age constraint on Burmese amber based on U-Pb dating of zircons. Cretaceous Res. 37:155–163.
Copyright (c) 2019 Journal of the Botanical Research Institute of Texas
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.