Biology:Trapa
Trapa is a genus of floating annual aquatic plants in the Lythraceae family. A well-known species in the genus is Trapa natans, grown as a food crop in China and the Indian subcontinent.
Trapa was formerly placed in the separate family Trapaceae. However, molecular phylogenetic studies have recovered Trapa as the sister group of Sonneratia, with the clade comprising these two genera sister to a clade comprising Lagerstroemia and Duabanga. This four-genus clade is deeply nested within Lythraceae, and the APG system therefore includes Trapa in Lythraceae.[1][2][3]
Evolution
Fossil record
The genus Trapa has an extensive fossil record, with numerous, distinctive species. Undisputed fossilized seeds have been found in Cenozoic strata starting from the Eocene throughout Europe, China and North America (though the genus became extinct in North America prior to the Pleistocene).[4] The oldest known fossils attributed to the genus are of leaves from Cretaceous Alaska, referred to the species, T. borealis.[5]
Taxonomy
The genus Trapa and its type species T. natans were named by the Swedish botanist Carl Linnaeus in his Species Plantarum in 1753.[6] The generic name Trapa is derived from a late Latin word for a caltrop, calcitrappa, an area denial weapon.[7] The specific name natans is the Latin for swimming or floating, from the verb nato, "I swim". As of 2023, there are eight recognised species, T. assamica, T. hankensis, T. hyrcana, T. incisa, T. kashmirensis, T. kozhevnikoviorum , T. natans, and T. nedoluzhkoi.[6][8]
References
- ↑ Graham, Shirley A.; Hall, Jocelyn; Sytsma, Kenneth; Shi, Suhua (2005). "Phylogenetic analysis of the Lythraceae based on four gene regions and morphology". International Journal of Plant Sciences 166 (6): 995–1017. doi:10.1086/432631.
- ↑ Inglis, Peter W.; Cavalcanti, Taciana B.; Facco, Marlon G.; Bakker, Freek T.; Graham, Shirley A. (2023). "A comprehensive genus-level phylogeny and biogeographical history of the Lythraceae based on whole plastome sequences". Annals of Botany 132 (2): 293–318. doi:10.1093/aob/mcad091.
- ↑ Angiosperm Phylogeny Group (2016). "An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG IV". Botanical Journal of the Linnean Society 181 (1): 1–20. doi:10.1111/boj.12385.
- ↑ "Torreya". Torrey Botanical Club.. August 3, 1912. https://books.google.com/books?id=rN4qAQAAIAAJ&q=trapa&pg=RA2-PA266.
- ↑ Hollick, Charles Arthur (1936). The Tertiary floras of Alaska, Issues 181–184. United States Government Print Office. p. 156. https://books.google.com/books?id=bmvnAAAAMAAJ&q=cretaceous+%22trapa%22+fossil&pg=PA156.
- ↑ 6.0 6.1 "Trapa Linnaeus, 1753". IRMNG. https://irmng.org/aphia.php?p=taxdetails&id=1375418.
- ↑ Palm, Natalie; Franzaring, Jürgen; Schweiger, Andreas H. (2024). "International Biological Flora: Trapa natans †: No. 5". Journal of Ecology 112 (10): 2386–2420. doi:10.1111/1365-2745.14372. Bibcode: 2024JEcol.112.2386P.
- ↑ "Trapa natans var. bispinosa (Lythraceae)". Botanica Wichita. 16 July 2025. https://botanica.org/two-spined-singhara-nut/.
Wikidata ☰ Q2487780 entry
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