Umkomasia is a genus of seed bearing organs produced by corystospermseed ferns, first based on fossils collected by Hamshaw Thomas from the Burnera Waterfall locality near the Umkomaas River of South Africa.[3] He recognized on the basis of cuticular similarities that the same plant produced pollen organs Pteruchus and the leaves Dicroidium. Various other corystosperm seed bearing organs from the Jurassic and Cretaceous have been assigned to this genus, but recently have been given distinct genera, with Umkomasia being restricted to the Triassic.[4]
^Gongle Shi; Andrew B. Leslie; Patrick S. Herendeen; Fabiany Herrera; Niiden Ichinnorov; Masamichi Takahashi; Patrick Knopf & Peter R. Crane (2016). "Early Cretaceous Umkomasia from Mongolia: implications for homology of corystosperm cupules". New Phytologist. 210 (4): 1418–1429. doi:10.1111/nph.13871. PMID 26840646.
^However, Rothwell & Stockey (2016) transferred this species to the genus Doylea. See: Gar W. Rothwell; Ruth A. Stockey (2016). "Phylogenetic diversification of Early Cretaceous seed plants: The compound seed cone of Doylea tetrahedrasperma". American Journal of Botany. 103 (5): 923–937. doi:10.3732/ajb.1600030. PMID 27208360.
^ abThomas, H.H. (1933). "On some pteridospermous plants from the Mesozoic rocks of South Africa". Philosophical Transactions of the Royal Society B. 222 (483–493): 193–265. doi:10.1098/rstb.1932.0016.
^Anderson, Heidi M.; Barbacka, Maria K.; Bamford, Marion K.; Holmes, W. B. Keith; Anderson, John M. (2019-01-02). "Umkomasia (megasporophyll): part 1 of a reassessment of Gondwana Triassic plant genera and a reclassification of some previously attributed". Alcheringa: An Australasian Journal of Palaeontology. 43 (1): 43–70. doi:10.1080/03115518.2018.1554748. ISSN 0311-5518. S2CID 134483119.
^Retallack G.J. (1977). "Reconstructing Triassic vegetation of southeastern Australia: a new approach to the biostratigraphy of Gondwanaland". Alcheringa. 1: 247–265. doi:10.1080/03115517708527763.
umkomasia, genus, seed, bearing, organs, produced, corystosperm, seed, ferns, first, based, fossils, collected, hamshaw, thomas, from, burnera, waterfall, locality, near, umkomaas, river, south, africa, recognized, basis, cuticular, similarities, that, same, p. Umkomasia is a genus of seed bearing organs produced by corystosperm seed ferns first based on fossils collected by Hamshaw Thomas from the Burnera Waterfall locality near the Umkomaas River of South Africa 3 He recognized on the basis of cuticular similarities that the same plant produced pollen organs Pteruchus and the leaves Dicroidium Various other corystosperm seed bearing organs from the Jurassic and Cretaceous have been assigned to this genus but recently have been given distinct genera with Umkomasia being restricted to the Triassic 4 UmkomasiaTemporal range Early Triassic Late Triassic PreꞒ Ꞓ O S D C P T J K Pg N Umkomasia macleanii ovulate structure Late Triassic Molteno Formation Umkomaas South Africa Scientific classification Kingdom Plantae Order Corystospermales Family Corystospermaceae Genus UmkomasiaThomas 1933 Species Umkomasia feistmantelii Early Triassic Australia Umkomasia macleanii Late Triassic South Africa Umkomasia mongolica Early Cretaceous Aptian Albian Mongolia 1 2 Umkomasia macleanii reconstruction with pollen organs Pteruchus africanus and leaves Dicroidium odontopteroides from the Late Triassic Molteno Formation of South Africa Contents 1 Description 2 Whole plant associations 3 Reassigned species 4 See also 5 References 6 External linksDescription editUmkomasia has helmet like cupules around ovules born in complex large branching structures Whole plant associations editUmkomasia feistmantelii from the Early Triassic of Australia may have been produced by the same plant as Pteruchus barrealensis pollen organs and Dicroidium zuberi leaves 5 Umkomasia macleanii from the Late Triassic of South Africa may have been produced by the same plant as Pteruchus africanus pollen organs and Dicroidium odontopteroides leaves 3 6 Reassigned species editU franconica Lower Jurassic Germany reassigned to the genus Kirchmuellia U asiatica Triassic China reassigned to the genus Stenorachis U mongolica Lower Cretaceous Mongolia moved to the genus Doylea See also editEvolution of plantsReferences edit Gongle Shi Andrew B Leslie Patrick S Herendeen Fabiany Herrera Niiden Ichinnorov Masamichi Takahashi Patrick Knopf amp Peter R Crane 2016 Early Cretaceous Umkomasia from Mongolia implications for homology of corystosperm cupules New Phytologist 210 4 1418 1429 doi 10 1111 nph 13871 PMID 26840646 However Rothwell amp Stockey 2016 transferred this species to the genus Doylea See Gar W Rothwell Ruth A Stockey 2016 Phylogenetic diversification of Early Cretaceous seed plants The compound seed cone of Doylea tetrahedrasperma American Journal of Botany 103 5 923 937 doi 10 3732 ajb 1600030 PMID 27208360 a b Thomas H H 1933 On some pteridospermous plants from the Mesozoic rocks of South Africa Philosophical Transactions of the Royal Society B 222 483 493 193 265 doi 10 1098 rstb 1932 0016 Anderson Heidi M Barbacka Maria K Bamford Marion K Holmes W B Keith Anderson John M 2019 01 02 Umkomasia megasporophyll part 1 of a reassessment of Gondwana Triassic plant genera and a reclassification of some previously attributed Alcheringa An Australasian Journal of Palaeontology 43 1 43 70 doi 10 1080 03115518 2018 1554748 ISSN 0311 5518 S2CID 134483119 Retallack G J 1977 Reconstructing Triassic vegetation of southeastern Australia a new approach to the biostratigraphy of Gondwanaland Alcheringa 1 247 265 doi 10 1080 03115517708527763 Retallack G J amp Dilcher D L 1988 Reconstructions of selected seed ferns Missouri Botanical Garden Annals 75 3 1010 1057 doi 10 2307 2399379 JSTOR 2399379 External links edit Fossilworks Lepidopteris paleodb org Retrieved 2016 03 18 Retrieved from https en wikipedia org w index php title Umkomasia amp oldid 1049959117, wikipedia, wiki, book, books, library,
