Ravenea

Last updated

Ravenea
Ravenearivularis.jpg
Ravenea rivularis
Scientific classification OOjs UI icon edit-ltr.svg
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Monocots
Clade: Commelinids
Order: Arecales
Family: Arecaceae
Subfamily: Ceroxyloideae
Tribe: Ceroxyleae
Genus: Ravenea
C.D.Bouché
Synonyms [1]
  • RaneveaL.H.Bailey
  • LouveliaJum. & H.Perrier

Ravenea is a genus of 20 known species of palms, all native to Madagascar and the Comoros. [1] [2]

Contents

They are small to large, dioecious palms, with solitary, robust grey stems, swollen at base and gradually tapering upward. The species vary greatly in size, with R. hildebrandtii and R. nana only reaching 4 m, while R. robustior and R. sambiranensis both reach 30 m. The leaves are up to 2–5 m long, pinnately compound, reduplicate, erect at first then arching, twisted near the apex; with numerous crowded narrow ribbed leaflets. The inflorescence is short, borne among the leaves; the fruit is a red drupe. [3] One particular species, Ravenea rivularis , is commonly cultivated as a houseplant and grown indoors all over the world. However, it is actually considered a vulnerable species in its wild habitat with fewer than 900 trees growing naturally.

Species

ImageScientific nameConservation StatusDistribution
Ravenea albicans.jpg Ravenea albicans (Jum.) Beentje Endangered northeast Madagascar
Ravenea beentjei Rakotoarin. & J.Dransf Critically endangered Vondrozo, Madagascar
Ravenea cycadifolia J.Dransf.Madagascar.
Ravenea declivium J.Dransf. & Rakotoarin. Critically endangered Madagascar.
Ravenea delicatula Rakotoarin. Critically endangered northwest Madagascar
Ravenea dransfieldii Beentje Endangered Madagascar.
Ravenea glauca kz1.JPG Ravenea glauca Jum. & H.Perrier Vulnerable species Madagascar.
Ravenea hildebrandtii H.Wendl. ex Bouché Endangered Comoros.
Ravenea hypoleuca Rakotoarin. & J.Dransf. Critically endangered southeast Madagascar
Ravenea julietiae Beentje Endangered Madagascar.
Ravenea krociana Beentje Endangered Madagascar.
Ravenea lakatra (Jum.) Beentje Critically endangered Madagascar.
Ravenea latisecta Jum. Critically endangered eastern central Madagascar.
Ravenea louvelii Beentje Critically endangered Madagascar
Ravenea madagascariensis kz1.JPG Ravenea madagascariensis Becc. Least concern Madagascar.
Ravenea moorei Kew Gardens.jpg Ravenea moorei J.Dransf. & N.W.Uhl Critically endangered Comoros.
Ravenea musicalis Beentje Critically endangered Madagascar
Ravenea nana Beentje Endangered Madagascar
AdultMajestyPalmFlorida.png Ravenea rivularis Jum. & H.Perrier Critically endangered Madagascar
Ravenea robustior kz1.JPG Ravenea robustior Jum. & H.Perrier Near threatened Madagascar
Ravenea sambiranensis Jum. & H.Perrier Least concern Madagascar
Ravenea xerophila 1zz.jpg Ravenea xerophila Jum. Vulnerable species Madagascar

Most of the species are endangered. Species such as R. moorei are critically so, with only two specimens known, last seen in 1993 (IUCN report). R. louvelii is little better off, with fewer than 25 plants known (IUCN report). Overall, less than 50 trees of several species are still alive. Historical data indicates that populations are still decreasing for most, except for Ravenea sambiranesis and Ravenea madagascariensis. The species listed as critically endangered will most likely become extinct this century unless measures are taken to cultivate new trees and protect their habitats from being disrupted by deforestation and water pollution. Even if as few as a dozen trees of each species were planted on ideal, protected land where they could reproduce, it would give each species a much better chance for survival.

Cultivation and uses

Ravenea rivularis (majesty palm) is widely cultivated in subtropical regions, and it is sold commercially as a houseplant. [4] It is an adaptable palm that looks somewhat similar to the ever-popular Queen palm. It is a very large palm with a large, untidy crown. It has symmetrical leaves and develops an attractive swollen base of the trunk. Majesty palms prefer full sun, plenty of water, and high humidity to ensure healthy growth. It is tolerant of different soil types. Propagation is by seeds, which germinate in 2–3 months.

Pinnate leaves characteristic to Ravenea Ravenea rivularis 2zz.jpg
Pinnate leaves characteristic to Ravenea

Related Research Articles

<i>Aiphanes</i> Genus of spiny palms native to tropical South and Central America and the Caribbean

Aiphanes is a genus of spiny palms which is native to tropical regions of South and Central America and the Caribbean. There are about 26 species in the genus, ranging in size from understorey shrubs with subterranean stems to subcanopy trees as tall as 20 metres (66 ft). Most have pinnately compound leaves ; one species has entire leaves. Stems, leaves and sometimes even the fruit are covered with spines. Plants flower repeatedly over the course of their lifespan and have separate male and female flowers, although these are borne together on the same inflorescence. Although records of pollinators are limited, most species appear to be pollinated by insects. The fruit are eaten by several birds and mammals, including at least two species of amazon parrots.

<i>Jubaea</i> Genus of palms

Jubaea is a genus of palms with one species, Jubaea chilensis, commonly known in English as the Chilean wine palm or Chile cocopalm, and palma chilena in Spanish. It is native to southwestern South America and is endemic to a small area of central Chile between 32°S and 35°S in southern Coquimbo, Valparaíso, Santiago, O'Higgins, and northern Maule regions.

<i>Beaucarnea recurvata</i> Species of tree

Beaucarnea recurvata, the elephant's foot or ponytail palm, is a species of flowering plant in the family Asparagaceae. The species was native to numerous states of eastern Mexico but is now confined to the state of Veracruz. Despite its common name, it is not closely related to the true palms (Arecaceae). It has become popular in Europe and worldwide as an ornamental plant. There are 350-year-old Beaucarneas registered in Mexico.

<i>Ulmus gaussenii</i> Species of tree

Ulmus gausseniiW. C. Cheng, the Anhui, or hairy, elm, is a medium size deciduous tree whose natural range is restricted to the valleys of the Langya limestone mountains of Chu Xian in Anhui Province, eastern China. The tree was most commonly found on the flood plains, indicating a tolerance of periodic inundation. However, U. gaussenii is now possibly the rarest and most endangered elm species, with only approximately 30 trees known to survive in the wild in 2009.

<i>Ceroxylon quindiuense</i> Species of palm

Ceroxylon quindiuense, often called Quindío wax palm, is a palm native to the humid montane forests of the Andes in Colombia and Peru.

<i>Pseudophoenix ekmanii</i> Species of palm

Pseudophoenix ekmanii is a palm species endemic to the Barahona Peninsula and Isla Beata in the Dominican Republic on the Caribbean island of Hispaniola.

<i>Attalea crassispatha</i> Species of palm

Attalea crassispatha is a palm which is endemic to southwest Haiti. The most geographically isolated member of the genus, it is considered a critically endangered species and has been called one of the rarest palms in the Americas.

Erythrina schliebenii is a species of legume in the family Fabaceae. It is found only in Tanzania. The species is named for German collector and botanist Hans-Joachim Schlieben.

<i>Sonchus brassicifolius</i> Species of plant

Sonchus brassicifolius, synonym Dendroseris litoralis, is a species of flowering plant in the daisy and sunflower family Asteraceae. It is a small evergreen tree species known as the cabbage tree. It is endemic to the Juan Fernández Islands, which lie in the southeast Pacific, off the west coast of Chile. It is native only to the tiny, volcanic Robinson Crusoe Island, home of the famed Juania australis and many other endemic plants. The species is threatened by habitat loss and has been brought back from the brink of extinction. It had been reduced to only a few individuals by feral goats on the island, and is still considered critically endangered.

<i>Ceroxylon</i> Genus of palms

Ceroxylon is a genus of flowering plants in the family Arecaceae, native to the Andes in Venezuela, Colombia, Ecuador, Peru, and Bolivia, known as Andean wax palms.

<i>Latania</i> Genus of palms

Latania, commonly known as latan palm or latania palm, is a genus of flowering plant in the palm tree family, native to the Mascarene Islands in the western Indian Ocean.

<i>Phoenicophorium</i> Genus of palms

Phoenicophorium, the thief palm, is a monotypic genus of flowering plant in the family Arecaceae. The sole species is Phoenicophorium borsigianum.

<i>Ravenea albicans</i> Species of plant in the family Arecaceae

Ravenea albicans is a species of flowering plant in the Arecaceae family. It is a palm endemic to northeast Madagascar and found in seven fragmented locations between the towns of Ampasimanolotra and Antalaha with the exception of one location much farther south near Vondrozo. It is an endangered species threatened by habitat loss. There are perhaps 200 mature individuals remaining. In its natural range it tends to grow in humid forests within northeast Madagascar's mountain valleys. It is unique among the Ravenea genus because its pinnate leaves have an exotic, colorful appearance. Its species name, albicans, is derived from the Latin word for the color white, album, as is the word for albinism. The base of each frond is green, yet they become white to dark grey near the tip at maturity. Some individuals have completely white fronds.

Ravenea musicalis, or the river palm, is a species of flowering plant in the family Arecaceae. Also known by the Antanosy word "torendriky," meaning "submerged trunk", R. musicalis is known for being the only truly aquatic palm tree. Like many mangrove trees, R. musicalis seeds germinate within the fruit, and the seedling takes root underwater. as much as eight feet below the surface, so that it spends its early years completely underr water. Endemic to Madagascar, R. musicalis was first discovered in 1993 by Henk Beentje on an expedition funded by the McDonald's restaurant. although of course it was ethnoknown by the Antanosy People for centuries. This palm is listed in the IUCN Red List. This tree is harvested by local people primarily for building material and food. Over-harvesting, habitat degradation and habitat loss threaten the remaining populations. Horticulturalists prize R. musicalis for its rarity and unique life history.

<i>Ravenea rivularis</i> Species of palm

Ravenea rivularis, the majestic palm, or majesty palm, is a species of tree in the family Arecaceae. They generally grow to 10 to 12 feet tall and are often marketed in stores as a "houseplant" in a pot, in its natural state, the majesty palm may sometimes grow to 98 feet tall.

<i>Pseudophoenix sargentii</i> Species of palm

Pseudophoenix sargentii, commonly known as the Florida cherry palm or buccaneer palm, is a medium-sized palm native to the northern Caribbean, eastern Mexico, and extreme southeast Florida in the United States.

<i>Coccothrinax crinita</i> Species of palm

Coccothrinax crinita is a palm which is endemic to Cuba. Like other members of the genus Coccothrinax, C. barbadensis is a fan palm.

Gaussia spirituana is a palm which is endemic to the Sierra de Jatibonico in east-central Cuba.

Dypsis humilis is a rare species of stemless palm that was discovered in Madagascar in 2007 by a collaboration between botanists from Madagascar and Royal Botanical Gardens, Kew. Fewer than ten plants were observed in an area that is threatened by logging and other human activity.

Beaucarnea olsonii is a plant in the family Asparagaceae, native to Mexico. The species is named for the botanist Mark E. Olson.

References

  1. 1 2 Kew World Checklist of Selected Plant Families
  2. Beentje, H. J. (1994). "A Monograph of Ravenea (Palmae: Ceroxyloideae)". Kew Bulletin. 49 (4): 623–671. Bibcode:1994KewBu..49..623B. doi:10.2307/4118064. JSTOR   4118064.
  3. Govaerts, R. & Dransfield, J. (2005). World Checklist of Palms: 1-223. The Board of Trustees of the Royal Botanic Gardens, Kew.
  4. Phillipson, P. (2017). "Ravenea rivularis". IUCN Red List of Threatened Species . 2017: e.T38677A67737451. doi: 10.2305/IUCN.UK.2017-2.RLTS.T38677A67737451.en . Retrieved 18 November 2021.