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Planera

Planera is a genus of flowering plants with a single living species, Planera aquatica, the planertree 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. 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. 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.

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Planera
Planera aquatica
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Embryophytes
Clade: Tracheophytes
Clade: Spermatophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Rosids
Order: Rosales
Family: Ulmaceae
Genus: Planera
J.F.Gmel.
Species

See text

Planera is a genus of flowering plants with a single living species, Planera aquatica,1 the planertree2 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

Species

Fossil species

  • †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

  • †Abelicea ungeri (Kováts ex Ettingshausen) Holmboe
  • †Cedrelospermum nervosum (Newberry) Manchester
  • †Chaetoptelea microphylla (Newberry) Hickey
  • †Fagopsis longifolia Lesquereux
References

References

  1. "Search results for Planera". The Plant List. Retrieved 1 March 2016.
  2. NRCS. "Planera aquatica". PLANTS Database. United States Department of Agriculture (USDA). Retrieved 7 October 2015.
  3. "Planera". The International Fossil Plant Names Index. Retrieved 8 Feb 2023.
  4. "Water Elm Ulmaceae Planera aquatica J.F. Gmel". Virginia Tech Department of Forestry and Environmental Conservation. Retrieved December 15, 2014.