Hesperocyparis Explained
Hesperocyparis (western cypress) is a genus of trees in the family Cupressaceae, containing North American species otherwise assigned to the genus Cupressus.[1] They are found throughout western North America. Only a few species have wide ranges, with most being restricted-range endemics.
Taxonomy
Members of Hesperocyparis were and still are placed in Cupressus by many authorities, but phylogenetic evidence supports a different affinity. A 2021 molecular study found Hesperocyparis to be the sister group to the genus Callitropsis (containing only the Nootka cypress), with this clade being sister to the Asian genus Xanthocyparis, containing only the Vietnamese golden cypress. The clade comprising all three genera was found to be sister to a clade containing Juniperus and Cupressus sensu stricto.[2] If Hesperocyparis and the other smaller genera were reunited with Cupressus it may also require them to be merged into a larger genus including Juniperus.[3]
As of 2024 Hesperocyparis is listed as the correct classification by Plants of the World Online,[4] World Flora Online,[5] and the Gymnosperm Database.[6] There is disagreement about this classification, with some scientists continuing to use Cupressus in preference to Hesperocyparis.[7] [8]
At the species level there is also uncertainty as to the number of species. In part this is because the north west of Mexico has not been sufficiently surveyed to give enough information to definitively determine if a number of species there and in the southwestern United States are fully separate species or part of a species complex.
Phylogeny
Additional species:
Notes and References
- Robert P. Adams, Jim A. Bartel & Robert A. Price . 2009 . A new genus, Hesperocyparis, for the cypresses of the Western Hemisphere . . 91 . 1 . 160–185 .
- Stull. Gregory W.. Qu. Xiao-Jian. Parins-Fukuchi. Caroline. Yang. Ying-Ying. Yang. Jun-Bo. Yang. Zhi-Yun. Hu. Yi. Ma. Hong. Soltis. Pamela S.. Soltis. Douglas E.. Li. De-Zhu. July 19, 2021. Gene duplications and phylogenomic conflict underlie major pulses of phenotypic evolution in gymnosperms. Nature Plants. en. 7. 8. 1015–1025. 10.1038/s41477-021-00964-4. 34282286 . 232282918 . 2055-0278.
- Book: Christenhusz . Maarten J. M. . Fay . Michael F. . Chase . Mark W. . Plants of the world : an illustrated encyclopedia of vascular plants . 2017 . Kew Publishing, Royal Botanic Gardens, Kew & The University of Chicago Press . Richmond, Surrey, UK & Chicago, Illinois . 978-1-84246-634-6 . 84 . 18 February 2024.
- 60451544-2 . Hesperocyparis Bartel & R.A.Price . 30 January 2024.
- Hesperocyparis Bartel & R.A.Price . 4000017629 . 30 January 2024.
- Web site: Earle . Christopher J. . Hesperocyparis (New World Cypresses) description . The Gymnosperm Database . 30 January 2024 . en.
- Michalet . Richard . Carcaillet . Christopher . Delerue . Florian . Domec . Jean-Christophe . Lenoir . Jonathan . Assisted migration in a warmer and drier climate: less climate buffering capacity, less facilitation and more fires at temperate latitudes? . Oikos . 19 December 2023 . 10.1111/oik.10248 . 266410521 . 13 February 2024.
- Book: Raddi . Paolo . Della Rocca . Gianni . Danti . Roberto . Stimm . B. . Roloff . A. . Lang . U.M. . Weisgerber . H. . Enzyklopädie der Holzgewächse: Handbuch und Atlas der Dendrologie /begründet von Peter Schütt. Andreas Roloff; Horst Weisgerber; Ulla M. Lang; Bernd Stimm . 8 January 2020 . Wiley-VCH . Weinheim . 9783527321414 . en . Cupressus glabra.
- Stull. Gregory W.. Qu. Xiao-Jian. Parins-Fukuchi. Caroline. Yang. Ying-Ying. Yang. Jun-Bo. Yang. Zhi-Yun. Hu. Yi. Ma. Hong. Soltis. Pamela S.. Soltis. Douglas E.. Li. De-Zhu. July 19, 2021. Gene duplications and phylogenomic conflict underlie major pulses of phenotypic evolution in gymnosperms. Nature Plants. en. 7. 8. 1015–1025. 10.1038/s41477-021-00964-4. 34282286. 236141481. 2055-0278.
- Web site: Stull . Gregory W. . et al. . 2021 . main.dated.supermatrix.tree.T9.tre . Figshare . 10.6084/m9.figshare.14547354.v1 .
