Valviloculus pleristaminis gen. et sp. nov., a Lauralean fossil flower with valvate anthers from mid-Cretaceous Myanmar amber
DOI:
https://doi.org/10.17348/jbrit.v14.i2.1014Abstract
The flower described here as Valviloculus pleristaminis, a new genus and species of fossil angiosperms, was obtained from Myanmar amber deposits dating to the mid-Cretaceous period. The flower is staminate, with an ovoid, hollow floral cup. The perianth consists of 6 tepals, one of which was lost prior to preservation. Numerous helically arranged stamens are borne at the summit of the flower. The anthers are bilocular, with pollen sacs that dehisce by laterally hinged valves. The tip of the connective bears a cup-shaped appendage. The gynoecium is represented only by a cluster of vestigial styles centered among the stamens. The fossil is provisionally assigned to order Laurales, its closest affinities being with the families Monimiaceae and Atherospermataceae.
Literaturhinweise
Chambers, K.L. & G.0. Poinar, Jr. 2020. Thymolepis toxandra gen. et sp. nov., a mid-Cretaceous fossil flower with horseshoeshaped anthers. J. Bot. Res. Inst. Texas 14:57–64.
Cohen, K.M., S. Finney, & P.L. Gibbard. 2013. International Chronostratigraphic Chart. International Commission on Stratigraphy. www.stratigraphy.org
Crepet, W.L., K.C. Nixon, D. Grimaldi, & M. Ricc io. 2016. A mosaic Lauralean flower from the Early Cretaceous of Myanmar. Amer. J. Bot. 103:290–297.
Cruickshank, R.D. & K. Ko. 2003. Geology of an amber locality in the Hukawng Valley, northern Myanmar. J. Asian Earth Sci. 23:441–455.
Duyfj es, B.E.E. 1996. Hernandiaceae. In: Flora Malesiana, Ser. 1, 12:737–761.
Endress, P.K. 1980a. Ontogeny, function and evolution of extreme floral construction in Monimiaceae. Pl. Syst. Evol. 134:79–120.
Endress, P.K. 1980b. Floral structure and relationships of Hortonia (Monimiaceae). Pl. Syst. Evol. 133:199–221.
Endress, P.K. 1992. Protogynous flowers in Monimiaceae. Pl. Syst. Evol. 181:227–232.
Endress, P.K. & L.D. Hufford. 1989. The diversity of stamen structures and dehiscence patterns among Magnoliidae. Bot. J. Linn. Soc. 100:45–85.
Endress, P.K. & S. Stumpf. 1990. Non-tetrasporangiate stamens in the angiosperms: Structure, systematic distribution and evolutionary aspects. Bot. Jahrb. Syst. 112:193–240.
Endress, P.K. & D.H. Lorence. 2004. Heterodichogamy of a novel type in Hernandia (Hernandiaceae) and its structural basis. Int. J. Pl. Sci. 165:753–763.
Foreman, D.B. & F.B. Sampson. 1987. Pollen morphology of Palmeria scandens and Wilkiea huegellana (Monimiaceae). Grana 26:127–133.
Foreman, D.B. & T. Whiffin. 2007. Daphnandra. In: A.J.G. Wilson, ed. Flora of Australia. CSIRO Publishing, Collingwood, Australia. 2:95–100.
Friis, E.M., P.R. Crane, & K.R. Pedersen. 2013. Early flowers and angiosperm evolution, Cambridge University Press, Cambridge, UK.
Hall, R. 2012. Late Jurassic-Cenozoic reconstructions of the Indonesian region and the Indian Ocean. Tectonophysics 570(571):1–41.
Kubitzki, K. 1993. Hernandiaceae. In: K. Kubitzki, J.G. Rohwer, and V. Bittrich, eds. The families and genera of vascular plants. Springer Verlag, Berlin, Germany 2:334–338.
Liu, Z-J., D. Huang, C. Cai, & X. Wang. 2018. The core eudicot boom registered in Myanmar amber. Sci. Rep. 8:16765.
Lorence, D.H. 1985. A monograph of the Monimiaceae (Laurales) in the Malagasy region (Southwest Indian Ocean). Ann. Missouri Bot. Gard. 72:1–165.
Mabberly, D.J. 2008. Mabberley’s plant book. Ed. 3. Cambridge University Press, Cambridge, UK.
Metcalfe, I. 1990. Allochthonous terrane processes in Southeast Asia. Phil. Trans. Roy. Soc. London A133:625–640.
Perkins, J. & E. Gilg. 1901. Monimiaceae. In: A. Engler, ed. Das Pflanzenreich. Verlag Wilhelm Engelmann, Leipzig, Germany. IV. 101:1–122.
Philipson, W.R. 1993. Monimiaceae. In: K. Kubitzki, J.G. Rohwer, and V. Bittrich, eds. The families and genera of vascular plants. Springer Verlag, Berlin, Germany. 2:426–437.
Poinar, G.O., Jr. 2017. A mid-Cretaceous Lauraceae flower, Cascolaurus burmitis gen. et sp. nov., in Myanmar amber. Cretaceous Res. 71:96–101.
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. 2018. Setitheca lativalva gen. et sp. nov., a fossil flower of Laurales from mid-Cretaceous Myanmar amber. J. Bot. Res. Inst. Texas 12:643–653.
Poinar, G.O., Jr. & K.L. Chambers. 2019. Zygadelphus aetheus gen. et sp. nov., an unusual fossil flower from mid-Cretaceous Myanmar amber. J. Bot. Res. Inst. Texas 13:467–473.
Poinar, G.O., Jr. & K.L. Chambers. 2020a. Dasykothon leptomiscus gen. et sp. nov., a fossil flower of possible Lauralean affinity from Myanmar amber. J. Bot. Res. Inst. Texas 14:65–71.
Poinar, G.O., Jr. & K.L. Chambers. 2020b. Phantophlebia dicycle gen. et sp. nov., a five-merous fossil flower in mid-Cretaceous Myanmar amber. J. Bot. Res. Inst. Texas 14:73–80.
Poinar, G.O., Jr. & K.L. Chambers. 2020c. Cyathitepala papillosa gen. et sp. nov., a mid-Cretaceous fossil flower from Myanmar amber with valvate anthers. J. Bot. Res. Inst. Texas 14:351–358.
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.
Rangin, C. 2017. Active and recent tectonics of the Burma Platelet in Myanmar. In: A.J. Barber, K. Zaw, and M.J. Crow, eds. Myanmar: Geology, resources and tectonics. Mem. Geol. Soc. London 48:53–64.
Renner, S.S. 1998. Phylogenetic affinities of Monimiaceae based on cpDNA gene and spacer sequences. Perspect. Pl. Ecol. Evol. Syst. 1:61–77.
Renner, S.S. 1999. Circumscription and phylogeny of the Laurales: Evidence from molecular and morphological data. Amer. J. Bot. 86:1301–1315.
Renner, S.S. 2004. Variation in diversity among Laurales, Early Cretaceous to present. Biol. Skr. 55: 441–458.
Renner, S.S., J.S. Struk, D. Strasberg, & C. Thebaud. 2010. Biogeography of the Monimiaceae (Laurales): A role for East Gondwana and long-distance dispersal, but not West Gondwana. J. Biogeog. 37:1227–1238.
Ross, A.J. 2018. Burmese (Myanmar) amber taxa, on-line checklist v. 2018.2. www.nms.ac.uk/explore/stories/natural-world/burmese-amber/
Sampson, F.B. 1996. Pollen morphology and ultrastructure of Laurelia, Laureliopsis, and Dryadodaphne (Atherospermataceae [Monimiaceae]). Grana 35:257–265.
Sampson, F.B. 2000. Pollen diversity in some modern Magnoliids. Int. J. Pl. Sci. 161(6 Suppl.):S193–S210.
Sampson, F.B. & D.B. Foreman 1988. Pollen morphology of Atherosperma, Daphnandra and Doryphora (Atherospermataceae [Monimiaceae]}. Grana 27:17–25.
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.
