Dehaasia

Dehaasia
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Magnoliids
Order:	Laurales
Family:	Lauraceae
Genus:	Dehaasia Lam.
Species
53, including:

Dehaasia is a genus of evergreen or deciduous trees or shrubs belonging to the Laurel family, Lauraceae. It is a botanical genus to 53 species of flowering plants belonging to the family Lauraceae. Distributed from continental Asia, from India to China, and islands from Borneo, New Guinea, Java, and Indonesia. The genus was described by Carl Ludwig Blume and published in Rumphi 1: 161 in 1837. (Jun 1837).

Overview

About 35 species in Cambodia, China, Indonesia, Laos, Malaysia, Myanmar, Philippines, Thailand, Vietnam, with the center of diversity in west Malaysia; three species in China, two endemic.

Dehaasia, Alseodaphne, and Nothaphoebe are, morphologically, three closely related but distinct genera near to the Persea subgroup of the Lauraceae. A total of 214 binomials of the three genera have been published by various authors (International Plant Names Index, March 2007), of which 44 have been attributed to species occurring in Borneo. Despite many attempts by various authors, Rohwer in 1993, and 2000, Van der Werff & Richter 1996, Van der Werff in 2001, to clarify the generic delimitation between these three genera, to date there remains to be no satisfactory solution. The taxonomy of the genus is poorly understood due to their diversity, difficulty in identifying and reduced taxonomic work done on it. Dehaasia are tropical species of very different sizes, morphology, and ecology. Because of the lack of worldwide knowledge about the family Lauraceae in general, very little is known about the genera diversity. The knowledge of this genus to national level, is that to be expected in countries with limited economic means with the vast majority of species indeterminate or even poorly determined. Therefore an increase in the study of genera, at national level, is of utmost importance for the progress of the systematics of the family Lauraceae in general. The increase in the number of species is expected for the genera, bringing an expected considerable increase in the total number of species of the family. The exact relationships among the genera in the family remained unclear.

Description

Shrubs or small hermaphrodite trees, up to 5 m tall. They are bush or trees of medium size. Branchlets yellow-white initially but soon grayed, slender, glabrous, warty, lenticellate, with distinctive leaf scars; young ones more or less angled; innovation covered with long and finely appressed hairs. The leaves are alternate. The bark is usually white, soft, papery, peels easily, with the xylem yellow. White twigs, thin and stiff, with visible signs of scarring produced by the leaves. The sheet s are grouped at the apex of the twig: The inflorescence s in tassel s arm, generally thin with many bracts so few flowers, usually upright and branched at right angles. The fruit is black and shiny, usually ovoid, rarely globose and the exocarp meaty. Fruit black, shiny, usually ovoid, rarely globose, with fleshy exocarp; fruit stalk generally scarlet or yellow or green, fleshy-dilated, obconical, warty, apex nearly depressed and rarely with persistent perianth lobes. The dispersal of seeds is due to birds that swallow them, so the berries are shaped to attract the birds. The fruits are an important food source for birds.

Selected species

Some names in the repository Global Names Index of uBio:

• Dehaasia acuminata Koord. & Valeton
• Dehaasia annamensis Kosterm.
• Dehaasia assamica Kosterm.
• Dehaasia borneensis Fern.-Vill.
• Dehaasia brachybotrys (Merr.) Kosterm.
• Dehaasia Blume, 1837.
• Dehaasia caesia Blume.
• Dehaasia cairocan (Vidal) C.K. Allen.
• Dehaasia candolleana (Meisn.) Kosterm.
• Dehaasia celebica Kosterm.
• Dehaasia chatacea
• Dehaasia corynantha Kosterm.
• Dehaasia cuneata

External links

• Dehaasia en eFlora
• A synopsis of the genus Dehaasia Bl. (Lauraceae)
• Chemical constituents from Dehaasia triandra. 1. Three new alkaloids, isocorydione, norisocorydione, and dehatriphine, from the leaves
• Chemical constituents from Dehaasia triandra. II. Five new alkaloids, secoxanthoplanine, dehydroisocorydione, 11, 8′-O-bisisocorydine,(8, 8′-R)-and (8, 8′-S)