Planera is a genus of flowering plants with a single living species, Planera aquatica,[1] the planertree[2] or water elm. The genus has an extensive fossil record dating back to the Cretaceous and spanning the northern hemisphere, with a few southern hemisphere records as well.[3] The living species is found in the southeastern United States, it is a small deciduous tree 10–15 m (390–590 in) tall, closely related to the elms but with a softly, prickly nut 10–15 mm (0.39–0.59 in) diameter, instead of a winged seed. It grows, as the name suggests, on wet sites. Despite its common English name, this species is not a true elm, although it is a close relative of the elms (species of the genus Ulmus). It is also subject to Dutch elm disease, a disease which affects only members of the Ulmaceae. It is native to most of the southeast United States. It is hardy down to Zone 7.[4]
| Planera | |
|---|---|
| |
| Planera aquatica | |
Scientific classification 
| |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Eudicots |
| Clade: | Rosids |
| Order: | Rosales |
| Family: | Ulmaceae |
| Genus: | Planera J.F.Gmel. |
| Species | |
|
See text | |
Species
editFossil species
edit- †Planera antiqua Heer, 1883 (Santonian-Campanian; Paatuut Formation, Greenland)
- †Planera aquaticiformis Hollick, 1936 (Paleocene/Eocene; "Berg Lake flora", Alaska)
- †Planera australis Ettingshausen, 1887 (Late Cretaceous; Otago, New Zealand)
- †Planera chankaensis Pavlyutkin, 2005 (Miocene; Novokachalinsk, Russia)
- †Planera crenata Newberry, 1883 (jr homonym, replacement name P. lingualis)
- †Planera cretacea Berry, 1907 (Cretaceous; North Carolina)
- †Planera dubia Lesquereux, 1859 (Eocene, Chuckanut Formation, Washington)
- †Planera emarginata (Göppert) Heer, 1856 (Tortonian, Poland)
- †Planera ezoana Ôishi & Huzioka, 1954 (Eocene; Hokkaido, Japan)
- †Planera hebridica Simpson, 1961 ("Cenozoic"; Isle of Mull, Scotland)
- †Planera knowltoniana Newberry, 1896 (Cenomanian; Raritan Formation, Virginia)
- †Planera mullensis Simpson, 1961 ("Cenozoic"; Isle of Mull, Scotland)
- †Planera myricifolia (Lesquereux) Cockerell, 1908 (Priabonian; Florissant Formation, Colorado)
- †Planera parvula Saporta, 1888 (Oligocene; France)
- †Planera subkeaki (Rérolle) Saporta, 1888 (Tortonian; La Cerdagnya, France)
- †Planera thompsoniana Traverse, 1955 (Burdigalian; Brandon lignite, Vermont)
- †Planera ulmifolia Schloemer-Jäger, 1958 (Paleocene; Brøgger peninsula, Spitsbergen)
- †Planera variabilis Newberry, 1883 (Ypresian; Green River Formation, Wyoming)
Species formerly included in Planera
edit- †Abelicea ungeri (Kováts ex Ettingshausen) Holmboe
- †Cedrelospermum nervosum (Newberry) Manchester
- †Chaetoptelea microphylla (Newberry) Hickey
- †Fagopsis longifolia Lesquereux
References
edit- ^ "Search results for Planera". The Plant List. Retrieved 1 March 2016.
- ^ USDA, NRCS (n.d.). "Planera aquatica". The PLANTS Database (plants.usda.gov). Greensboro, North Carolina: National Plant Data Team. Retrieved 7 October 2015.
- ^ "Planera". The International Fossil Plant Names Index. Retrieved 8 Feb 2023.
- ^ "Water Elm Ulmaceae Planera aquatica J.F. Gmel". Virginia Tech Department of Forestry and Environmental Conservation. Retrieved December 15, 2014.