ORIGINAL ARTICLE
Two-seeded cones of probable gnetalean affinity from the Morrison Formation (Late Jurassic) of Utah and Colorado, USA
 
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1
Florida Museum of Natural History, Dickinson Hall, 1659 Museum Road, Gainesville, FL 32611-7800, USA
 
2
State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing, Jiangsu, China
 
3
Department of Paleobiology, NHB 121, National Museum of Natural History, Smithsonian Institution, Washington D.C., USA
 
4
Oak Spring Garden Foundation, 1776 Loughborough Lane, Upperville, VA 20184, USA
 
5
Yale School of the Environment, 195 Prospect Street, Yale University, New Haven, CT 06511-2387, USA
 
 
Online publication date: 2022-07-26
 
 
Publication date: 2022-07-26
 
 
Acta Palaeobotanica 2022; 62(2): 77-92
 
HIGHLIGHTS
  • Micro-CT scanning provides excellent surface details as well as some internal details of calcified cone remains.
  • Bassitheca is a new genus of gymnosperm cone with two seeds enveloped by decussately organized bracts.
  • The cones exhibit an unusual mode of dehiscence with a pair of lateral valves falling away from the central septum to release the two seeds.
KEYWORDS
ABSTRACT
Three dimensional calcitic casts of a two-seeded compound cone are described from the Upper Jurassic Brushy Basin Member of the Morrison Formation based on specimens from Colorado and Utah. Cones of Bassitheca hoodiorum gen. et sp. nov. are broadly obovate in face view, ~3.5 mm high, ~2.6 mm wide, and viewed from above have two planes of symmetry. Micro-CT scanning of numerous specimens shows that each cone has two well-developed orthotropous seeds positioned opposite each other in the major plane and separated by a median longitudinal septum in the minor plane. At a higher level in the cone, a median apical septum in the major plane separates two depressions arranged opposite each other. The two well-developed seeds in the major plane are enclosed by bracts, but numerous incomplete cones, together with cones showing lines of dehiscence, indicate that each seed was shed by the abscission of a lateral valve. One specimen indicates that three vascular bundles entered the base of each well-developed seed and these are interpreted as the vascular supply to the envelope of a chlamydospermous ovule. The opposite and decussate arrangement of bracts at the base of the cone, the paired arrangement of the two well-developed seeds perpendicular to the two apical depressions, combined with the inferred seed envelope that was apparently shed with the seed, indicates a probable relationship to Gnetales and specifically to extant Ephedra. Along with Dayvaultia tetragona Manchester et Crane, also known from the Brushy Basin Member of the Morrison Formation, Bassitheca hoodiorum provides further evidence that the Gnetales were more significant in the Morrison vegetation than has been recognized previously.
 
REFERENCES (58)
1.
Arnold, C.A., 1962. A Rhexoxylon-like stem from the Morrison of Utah. American Journal of Botany 49, 833–836. https://doi.org/10.1002/j.1537....
 
2.
Ash, S.R., 1994. First occurrence of Czekanowskia (Gymnospermae, Czekanowskiales) in the United States. Review of Palaeobotany and Palynology 81, 129–140. https://doi.org/10.1016/0034-6....
 
3.
Ash, S.R., Tidwell, W.D., 1998. Plant megafossils from the Brushy Basin Member of the Morrison Formation near Montezuma Creek Trading Post, southeastern Utah. Modern Geology 22, 321–339.
 
4.
Bass, C., 1964. Significant new fossil plant locality in Utah. Contributions to Geology University of Wyoming 3, 94–95.
 
5.
Bickner, M., Herrera, F., Herendeen, P.S., Shi, G., Ichinnorov, N., Crane, P.R., 2021. Three New Early Cretaceous Seeds from Mongolia with Chlamydospermous Organization. Conference: Botany 2021 Virtual! – July 18–23, Abstract available on-line: https://2021.botanyconference.....
 
6.
Carpenter, K., 1998. Vertebrate biostratigraphy of the Morrison Formation near Cañon City, Colorado. Modern Geology 23, 407–426.
 
7.
Chandler, M.E.J., 1966. Fruiting organs from the Morrison Formation of Utah, U.S.A. Bulletin of the British Museum (Natural History), Geology 12(4), 137–171. https://doi.org/10.5962/p.3138....
 
8.
Crane, P.R., Lidgard, S., 1989. Angiosperm diversification and paleolatitudinal gradients in Cretaceous floristic diversity. Science 246(4930), 675–678. https://doi.org/10.1126/scienc....
 
9.
Crane, P.R., Upchurch, G.R., 1987. Drewria potomacensis gen. et sp. nov., an Early Cretaceous member of Gnetales from the Potomac Group of Virginia. American Journal of Botany 74(11), 1722–1736. https://doi.org/10.1002/j.1537....
 
10.
Dayvault, R.D., Hatch, H.S., 2003. Short shoots from the Late Jurassic Morrison Formation of southeastern Utah. Rocks & Minerals 78(4), 232–247. https://doi.org/10.1080/003575....
 
11.
Dayvault, R.D., Hatch, H.S., 2007. Conifer cones from the Jurassic and Cretaceous rocks of eastern Utah. Rocks & Minerals 82(5), 382–397. https://doi.org/10.3200/RMIN.8....
 
12.
Dodson, P., Behrensmeyer, A.K., Bakker, R.T., Mcintosh, J.S., 1980. Taphonomy and paleoecology of the dinosaur beds of the Jurassic Morrison Formation. Paleobiology 6(2), 208–232.
 
13.
Endress, P.K., 1996. Structure and function of female and bisexual organ complexes in Gnetales. International Journal of Plant Sciences 157 (6, Supplement), S113–125. https://doi.org/10.1086/297407.
 
14.
Farjon, A. 2005. A monograph of Cupressaceae and Sciadopitys. Royal Botanic Gardens, London, 643 pp.
 
15.
Farjon, A., 2008. A natural history of conifers. Timber Press.
 
16.
Foster, J.R., 2020. Jurassic West, The dinosaurs of the Morrison Formation and their world. Indiana University Press, Bloomington, Indiana.
 
17.
Friis, E.M., Crane, P.R., Pedersen, K.R., 2011. Early flowers and angiosperm evolution. Cambridge University Press, Cambridge.
 
18.
Friis, E.M., Crane, P.R., Pedersen, K.R., 2013. New diversity among chlamydospermous seeds from the Early Cretaceous of Portugal and North America. International Journal of Plant Sciences 174(3), 530–558. https://doi.org/10.1086/668250.
 
19.
Friis, E.M., Crane, P.R., Pedersen, K.R., 2014. Welwitschioid diversity in the Early Cretaceous: Evidence from fossil seeds with pollen from Portugal and eastern North America. Grana 53, 175–176. https://doi.org/10.1080/001731....
 
20.
Friis, E.M., Crane, P.R., Pedersen, K.R., 2019. Chlamydospermous seeds document the diversity and abundance of extinct gnetalean relatives in Early Cretaceous vegetation. International Journal of Plant Sciences 180(7), 643–666. https://doi.org/10.1086/704356.
 
21.
Friis, E.M., Crane, P.R., Pedersen, K.R., Bengtson, S., Donoghue, P.C.J., Grimm, G.W., Stampanoni, M., 2007. Phase-contrast X-ray microtomography links Cretaceous seeds with Gnetales and Bennettitales. Nature 450, 549–552. https://doi.org/10.1038/nature....
 
22.
Friis, E.M., Pedersen, K.R., Crane, P.R., 2009. Early Cretaceous mesofossils from Portugal and eastern North America related to the Bennettitales-Erdtmanithecales-Gnetales group. American Journal of Botany 96, 252–283. https://doi.org/10.3732/ajb.08....
 
23.
Gee, C.T., 2011. Dietary options for the sauropod dinosaurs from an integrated botanical and paleobotanical perspective. In: Klein, N., Remes, K., Gee, C.T., Sander, P.M. (eds), Biology of the Sauropod dinosaurs: Understanding the Life of Giants. Indiana University Press, Bloomington and Indianapolis, Indiana, pp. 34–56.
 
24.
Gee, C.T., 2013. Applying micro CT and 3D visualization to Jurassic silicified conifer seed cones: A virtual advantage over thin-sectioning. Applications in Plant Sciences, 1(11), 1300039. https://doi.org/10.3732/apps.1....
 
25.
Gee, C.T., 2016. Emerging data on the Morrison flora: Opulent conifer forests or a hinterland xeriscape for the sauropods? Journal of Vertebrate Paleontology, Program and Abstracts 2016, 143–144.
 
26.
Gee, C.T., Tidwell, W.D., 2010. A mosaic of characters in a new whole-plant Araucaria, A. delevoryasii Gee sp. nov., from the Late Jurassic Morrison Formation of Wyoming, U.S.A. In: Gee, C.T. (ed.), Plants in Mesozoic time: Morphological innovations, phylogeny, ecosystems. Indiana University Press, Bloomington, Indiana, pp. 67–94.
 
27.
Gee, C.T., Dayvault, R.D., Stockey, R.A., Tidwell, W.D., 2014. Greater palaeobiodiversity in conifer seed cones in the Upper Jurassic Morrison Formation of Utah, USA. Palaeobiodiversity and Palaeoenvironments 94, 363–375. https://doi.org/10.1007/s12549....
 
28.
Gee, C.T., Sprinkel, D.A., Bennis, M.B., Gray, D.E., 2019. Silicified logs of Agathoxylon hoodii (Tidwell et Medlyn) comb. nov. from Rainbow Draw, near Dinosaur National Monument, Uintah County, Utah, USA, and their implications for araucariaceous conifer forests in the Upper Jurassic Morrison Formation. Geology of the Intermountain West 6, 77–92. https://doi.org/10.31711/giw.v....
 
29.
Herrera, F., Shi, G., Knopf, P., Leslie, A.B., Ichinnorov, N., Takahashi, M., Crane, P.R., Herendeen, P.S. 2016. Cupressaceae Conifers from the Early Cretaceous of Mongolia. International Journal of Plant Sciences 178, 19–41. https://doi.org/10.1086/689577.
 
30.
Hotton, C., Baghai-Riding, N., 2010. Palynological evidence for conifer dominance within a heterogeneous landscape in the Late Jurassic Morrison Formation, U.S.A. In: Gee, C.T. (ed.), Plants in Mesozoic Time; Morphological Innovations, Phylogeny, Ecosystems. Indiana University Press, Bloomington, Indiana, pp. 295–330.
 
31.
Hotton, C., Baghai-Riding, N., 2016. Palynology of the Late Jurassic Morrison Formation: New insights into floristics, paleoclimate, phytogeography, and tetrapod herbivory. Journal of Vertebrate Paleontology, Program and Abstracts 2016, 157.
 
32.
Kowallis, B., Deino, A.R., Peterson, F., Turner, C., 1998. High precision radiometric dating of the Morrison Formation. Modern Geology 22, 2356–2360.
 
33.
Krassilov, V.A., 1986. New floral structure from the Lower Cretaceous of Lake Baikal area. Review of Palaeobotany and Palynology 47, 9–16. https://doi.org/10.1016/0034-6....
 
34.
Kunzmann, L., Mohr, B.A., Wilde, V., Bernardes-de- Oliveira, M.E., 2011. A putative gnetalean gymnosperm Cariria orbiculiconiformis gen. nov. et spec. nov. from the Early Cretaceous of northern Gondwana. Review of Palaeobotany and Palynology 165(1–2), 75–95. https://doi.org/10.1016/j.revp....
 
35.
Litwin, R.J., Turner, C.E., Peterson, F., 1998. Palynological evidence for the age of the Morrison Formation, Western Interior, U.S. Modern Geology 22, 297–319.
 
36.
Manchester, S.R., Zhang, X., Hotton, C., Wing, S., Crane, P.R., 2021. Distinctive quadrangular seedbearing structures of gnetalean affinity from the Late Jurassic Morrison Formation of Utah, USA. Journal of Systematic Palaeontology 19, 743–760. https://doi.org/10.1080/147720....
 
37.
Medlyn, D.A., Tidwell, W.D., 1975a. Conifer wood from the Upper Jurassic of Utah, Part 1: Xenoxylon morrisonense sp. nov. American Journal of Botany 63(2), 203–208. https://doi.org/10.1002/j.1537....
 
38.
Medlyn, D.A., Tidwell, W.D., 1975b. Petrified plant remains from the Upper Jurassic Morrison Formation near Greybull, Wyoming. American Journal of Botany, Abstract Volume, 62, 22.
 
39.
Medlyn, D.A., Tidwell, W.D., 1979. A review of the genus Protopiceoxylon with emphasis on North American species. Canadian Journal of Botany 57, 1451–1463.
 
40.
Mendes, M.M., Pedersen, K.R., Friis, E.M., 2020. Battenispermum hirsutum gen. et sp. nov., a new Early Cretaceous seed from Portugal with chlamydospermous organisation. Cretaceous Research 109, 104376. (9 pp.). https://doi.org/10.1016/j.cret....
 
41.
Rodin, R.J., Kapil, R.N., 1969. Comparative anatomy of the seed coats of Gnetum and their probable evolution. American Journal of Botany 56(4), 420–431. https://doi.org/10.1002/j.1537....
 
42.
Rothwell, G.R., Stockey, R.A., 2013. Evolution and phylogeny of Gnetophytes: Evidence from the anatomically preserved seed cone Protoephedrites eamesii gen. et sp. nov. And the seeds of several Bennettitalean species. International Journal of Plant Sciences 174(3), 511–529. https://doi.org/10.1086/668688.
 
43.
Rydin, C., Pedersen, K.R., Crane, P.R., Friis, E.M., 2006a. Former diversity of Ephedra (Gnetales): evidence from Early Cretaceous seeds from Portugal and North America. Annals of Botany 98(1), 123–140. https://doi.org/10.1093/aob/mc....
 
44.
Rydin, C., Wu, S.Q., Friis, E.M., 2006b. Liaoxia Cao et SQ Wu (Gnetales): ephedroids from the Early Cretaceous Yixian Formation in Liaoning, northeastern China. Plant Systematics and Evolution, 262(3), 239–265. https://doi.org/10.1007/s00606....
 
45.
Rydin, C., Khodabendeh, A., Endress, P.K., 2010. The female reproductive unit of Ephedra (Gnetales); comparative morphology and evolutionary perspectives. Botanical Journal of the Linnean Society 163(4), 387–430. https://doi.org/10.1111/j.1095....
 
46.
Tidwell, W.D., 1990a. A new osmundaceous species (Osmundacaulis lemonii n. sp.) from the Upper Jurassic Morrison Formation, Utah. Hunteria 2(7), 1–11.
 
47.
Tidwell, W.D., 1990b. Preliminary report on the megafossil flora of the Upper Jurassic Morrison Formation. Hunteria 2(8), 1–11.
 
48.
Tidwell, W.D., 1994. Ashicaulis, a new genus for some species in Millerocaulis (Osmundaceae). Sida 16(2), 253–261.
 
49.
Tidwell, W.D., Ash, S.R., 1990. On the Upper Jurassic stem Hermanophyton and its species from Colorado and Utah, USA. Palaeontographica, Abt. B 218(4-6), 77–92.
 
50.
Tidwell, W.D., Ash, S.R., 2006. Preliminary report on the Early Jurassic flora from the St. George Dinosaur Discovery Site, Utah. In: Harris, J.D. Lucas, S.G, Spielmann, J.A., Lockley, M.G., Milner, A.R.C., Kirkland, J.I., Kirkland (eds), The Triassic–Jurassic Terrestrial Transition. New Mexico Museum of Natural History and Science Bulletin 37, 414–420.
 
51.
Tidwell, W.D., Medlyn, D.A., 1992. Short shoots from the Upper Jurassic Morrison Formation, Utah, Wyoming, and Colorado, USA. Review of Palaeobotany and Palynology 71(1-4), 219–238. https://doi.org/10.1016/0034-6....
 
52.
Tidwell, W.D., Medlyn, D.A., 1993. Conifer wood from the Upper Jurassic of Utah, USA–Part II: Araucarioxylon hoodii sp. nov. The Palaeobotanist 42(1), 70–77.
 
53.
Tidwell, W.D., Rushforth, S.R., 1970. Osmundacaulis wadei, a new osmundaceous species from the Morrison Formation (Jurassic) of Utah. Bulletin of the Torrey Botanical Club 97(3), 137–144. https://doi.org/10.2307/248334....
 
54.
Tidwell, W.D., Britt, B.B., Ash, S.R., 1998. Preliminary floral analysis of the Mygatt-Moore Quarry in the Jurassic Morrison Formation, west-central Colorado. Modern Geology 22(1-4), 341–378.
 
55.
Trujillo, K.C., Kowallis, B.J., 2015. Recalibrated legacy 40Ar/39Ar ages for the Upper Jurassic Morrison Formation, Western Interior, USA. Geology of the Intermountain West 2, 1–8.
 
56.
Yang, Y., Ferguson, D.K., 2015. Macrofossil evidence unveiling evolution and ecology of early Ephedraceae. Perspectives in Plant Ecology, Evolution and Systematics 17, 331–346. http://dx.doi.org/10.1016/j.pp....
 
57.
Yang, Y., Wang, Q., 2013. The earliest fleshy cone of Ephedra from the Early Cretaceous Yixian Formation of northeast China. PLoS ONE 8(1), e53652. https://doi.org/10.1371/journa....
 
58.
Zumajo-Cardona, C., Frangos, S., Stevenson, D.W., 2021. Seed anatomy and development in cycads and Ginkgo, keys for understanding the evolution of seeds. Flora 285, 151951. https://doi.org/10.1016/j.flor....
 
 
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