Nectandra

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Nectandra
Nectandra saligna.jpg
N. saligna
Scientific classification
Kingdom: Plantae
(unranked): Angiosperms
(unranked): Magnoliids
Order: Laurales
Family: Lauraceae
Genus: Nectandra
Rol. ex Rottb.
Species

See text.

Nectandra is a genus of plant in the family Lauraceae.

Overview[edit]

Plants from this genus have been used in the treatment of several clinical disorders in humans. It has been demonstrated that Nectandra plants have potential analgesic, antiinflammatory, febrifuge, energetic and hypotensive activities. Nectandra also has been investigated as a possible antitumoral agent and the presence of neolignans was suggested as potential chemotherapeutics. Crude extracts of Nectandra contain alkaloids and lignans, berberine and sipirine. Some authors have postulated that tannins play important roles as antioxidant compounds in the scavenging of free radicals. It is reported that an extract of N. salicifolia has potent relaxant activity on vascular smooth muscle. Researchers of the entire world agree that pre-clinical large studies on herbal medicine are important and urgent, specially high-quality clinical and pre-clinical trials.[1]

Description[edit]

They are trees and bushes, hermaphrodites. The leaves are alternate, entire, glabrous or pubescent, pinnatinervias, with longitudinal grooves. Simple, alternate, petiole 0.9 to 2.2 cm in length canalicular limbo 11 to 28 cm long and 5 to 11 cm wide, with 16-28 secondary veins; base acute decurrent and revolute, entire, apex elliptically shaped, green dark, and very oblique secondary veins visible on the underside. terminal buds whitish. The inflorescences are pseudo-axillary, paniculate, the last divisions cimosas, mostly somewhat pubescent, the flowers are small, rarely more than 1 cm in diameter, white or greenish tepals equal. The fruit is a bay set on a shallow dome. Drupa domed red-pink fleshy fruit ovoid, green when are immature and black when ripe.

Ecology[edit]

Nectandra cissiflora berry.

A neotropical genus with 114 species. The genus is similar to Ocotea with it is closely related, but the best characters to distinguish them are the position of the locules in the anther, in an arc in Nectandra,in 2 rows in Ocotea, papillose pubescence are present and the fact that Nectandra tepals are fused at the base itself and fall as a unit in the old flowers, while they are free in Nectandra in Ocotea fall individually. Many species are looking for timber.

Medium trees reach 60 cm in diameter, 25 m in height and they have a cup irregular. Bole straight and cylindrical, with modifications of low and thin fins in its base. Species are located mostly in the middle stratum of forest. Medium trees slender, with thin fins and downs[2]

The Family Lauraceae was part of Gondwanaland flora and many genera also, migrated to South America via Antarctica in ocean landbridges by Paleocene time. There they spread over most of the continent. When the North American and South American tectonic plates joined in late Neogene, volcanic mountain building created island chains which later formed the meso-American landbridge. Pliocene elevation created new habitats for speciation. While some genera died out in increasingly xerophytic Africa, starting with the freezing of Antarctica about 20 million years ago and the formation of the Benguela current, others, like Beilschmiedia, and Nectandra, which also reached south and meso-America, are still surviving today in Africa in a number of species. The genus Persea, however, died out in Africa, except for Persea indica, surviving in the fog shrouded mountains of the Canary Islands, which with Madagascar constitutes Africa's Laurel forest plant refugia. In meso-America, the genus Nectandra proliferated into new species and the berries of some of them constitute a valuable food supply for the quetzal, that lives in the montane rainforests of meso-America. Since this habitat is constantly threatened by encroching agriculture, the laurel forest animal or vegetal species had already become rare in many of its former habitats and are threatened by habitat loss.

The quetzal favorite fruits are berries of relatives of the avocado family. Their differing maturing times in the Cloud forest determine the migratory movements of the quetzals to differing elevation levels in the forests. With a gape width of 21 mm, the quetzal swallows the small berries (aquacatillos) whole, which he catches while flying through the lower canopy of the tree, and then regurgitates the seed within 100 meters from the tree. Wheelright in 1983 observed that parent quetzals take far less time intervals to deliver fruits to the young brood than insects or lizards, reflecting the ease of procuring fruits, as opposed to capturing animal prey. Since the young are fed exclusively berries in the first 2 weeks after hatching, these berries must be of high nutritional value. Usually only the total percentage of water, sugar, nitrogen, crude fats and carbohydrates are reported by ornithologists[3]

Species selected[edit]

It contains the following species (but this list may be incomplete):

References[edit]