Abstract
Species of Gordonia s.l. are characterized by having seeds with prominent flattened apical wings. However, recent molecular phylogenetic studies show that this concept of Gordonia is not monophyletic, with species occurring in two tribes of Theaceae. We examine seed coat micromophology of 14 species of Gordonia s.l., including representatives from all proposed lineages, and ten species from six genera from all three tribes of Theaceae. We observed that seeds from Gordonieae, including two species of Gordonia s.l., have irregularly protruding groups of cells on the seed coat that appear to be unique in the family. Seeds of Theeae, including all remaining species of Gordonia s.l., lack protruding cells and include testa cells that are isodiametric to elongate. Seeds of Stewartieae lack protrusions and elongate testa cells, and often have sculpting visible below the seed coat. Seeds of Gordonia s.l. from Gordonieae appear significantly smaller than species placed in Theeae. These results may help to infer relationships of fossilized seeds previously identified as Gordonia.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
Literature Cited
Airy-Shaw, H. K. 1936. Notes on the genus Schima and on the classification of the Theaceae-Camellioïdeae. Bulletin of Miscellaneous Information (Royal Gardens, Kew): 496–499.
Grote, P. J. & D. L. Dilcher. 1989. Investigations of Angiosperms from the Eocene of North America: A new genus of Theaceae based on fruit and seed remains. Botanical Gazette 150: 190–206.
——— & ———. 1992. Fruits and seeds of tribe Gordonieae (Theaceae) from the Eocene of North America. American Journal of Botany 79: 744–753.
Keng, H. 1962. Comparative morphological studies in Theaceae. University of California Publications in Botany 33: 269–384.
———. 1980. On the unification of Laplacea and Gordonia (Theaceae). Gardens’ Bulletin Singapore 33: 303–311.
———. 1984. Florae Malesianae precursores – LVIII, part two. The genus Gordonia (Theaceae) in Malesia. Gardens’ Bulletin Singapore 37: 1–47.
Kobuski, C. E. 1950. Studies in the Theaceae, XX. Notes on the South and Central American species of Laplacea. Journal of the Arnold Arboretum 31: 405–429.
Mabberley, D. J. 2008. Mabberley’s plant-book: A portable dictionary of plants, their classification and uses. Cambridge University Press, Cambridge.
Ming, T. L. & B. Bartholomew. 2007. Theaceae. Pp. 366–478. In Z. Y. Wu & P. H. Raven (eds.), Flora of China. Missouri Botanical Garden Press, St. Louis.
Orel, G., P. G. Wilson, A. S. Curry & H. T. Luu. 2012. Polyspora huongiana sp. nov. (Theaceae) from Vietnam and notes on related species. Nordic Journal of Botany 30: 47–52.
Prince, L. M. 2002. Circumscription and biogeographic patterns in the Eastern North American-East Asian genus Stewartia (Theaceae: Stewartieae): insight from chloroplast and nuclear DNA sequence data. Castanea 67: 290–301.
———. 2007. A brief nomenclatural review of genera and tribes in Theaceae. Aliso 24: 105–121.
———. 2009. Theaceae. Pp. 322–328. In: Flora of North America Editorial Committee (eds.), Flora of North America North of Mexico, volume 8. Oxford University Press, Oxford and New York.
——— & C. R. Parks. 2001. Phylogenetic relationships of Theaceae inferred from chloroplast DNA sequence data. American Journal of Botany 88: 2309–2320.
Sealy, J. R. 1958. A revision of the genus Camellia. The Royal Horticultural Society. London.
Stevens, P. F., S. Dressler & A. L. Weitzman. 2004. Theaceae. Pp. 463–471. In: K. Kubitzki (ed.), The families and genera of flowering plants, volume 6. Flowering Plants: dicotyledons (Celastrales, Oxalidales, Rosales, Cornales, Ericales). Springer-Verlag, Berlin.
Tsou, C.-H. 1997. Embryology of the Theaceae–anther and ovule development of Camellia, Franklinia, and Schima. American Journal of Botany 84: 369–381.
———. 1998. Early floral development of Camellioideae (Theaceae). American Journal of Botany 85: 1531–1547.
Wang, Y. H., H. He, T. L. Min, L. H. Zhou & P. W. Fritsch. 2006. The phylogenetic position of Apterosperma (Theaceae) based on morphological and karyotype characters. Plant Systematics and Evolution 260: 39–52.
Whitlock, B. A., J. Silver & J. S. Prince. 2010. Seed coat morphology in Gentianopsis (Gentianaceae). Rhodora 112: 58–79.
Yakandawala, D. M. D. & L. A. A. H. Gunathilake. 2008. Phylogenetic relationships of Gordonia Ellis (Theaceae) species endemic to Sri Lanka. Journal of the National Science Foundation, Sri Lanka 36: 51–58.
Yang, S.-X., J.-B. Yang, L.-G. Lei, D.-Z. Li, H. Yoshina & T. Ikeda. 2004. Reassessing the relationships between Gordonia and Polyspora (Theaceae) based on the combined analyses of molecular data from the nuclear, plastid and mitochondrial genomes. Plant Systematics and Evolution 248: 45–55.
Zona S., P. Davis, L. A. A. H. Gunathilake, J. Prince & J. W. Horn. 2012. Seeds of Eriocaulaceae of the United States and Canada. Castanea 77: 37–45.
Acknowledgments
The authors wish to thank the curatorial staff of the Arnold Arboretum (A), the Fairchild Tropical Botanic Garden (FTG), and The New York Botanic Garden (NY) for permission to sample specimens for this study, and the University of Miami for financial support. All imaging was carried out at the Dauer Electron Microscopy Laboratory of the University of Miami Biology Department. We thank Linda Prince and an anonymous reviewer for providing valuable feedback, and Soyeon Ahn of Department of Educational and Psychological Studies of the University of Miami for advice on statistical analyses. The authors also thank Prof. D. M. D. Yakandawala of the Department of Botany of the Faculty of Science at University of Peradeniya, Sri Lanka, for her assistance with fieldwork.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Gunathilake, L.A.A.H., Prince, J.S. & Whitlock, B.A. Seed coat micromorphology of Gordonia sensu lato (including Polyspora and Laplacea; Theaceae). Brittonia 67, 68–78 (2015). https://doi.org/10.1007/s12228-014-9347-z
Published:
Issue Date:
DOI: https://doi.org/10.1007/s12228-014-9347-z