Allomorphia (PROSEA)
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Introduction |
Allomorphia Blume
- Protologue: Flora 14: 522 (1831); Bijdr. Natuurk. Wetensch. 6: 262 (1831).
- Family: Melastomataceae
- Chromosome number: x= unknown;A. alata: 2n= 30-32
Origin and geographic distribution
Allomorphia consists of approximately 20 species, and occurs in tropical Asia: Indo-China, southern China, Thailand, Peninsular Malaysia, Sumatra and northern Borneo. Indo-China, Thailand and Peninsular Malaysia are richest in species, each with about 5-7 species.
Uses
There is some information on medicinal uses of Allomorphia in Peninsular Malaysia. Poultices of leaves have been applied to treat headache, fever and skin diseases, whereas a decoction of the roots is given to women after childbirth.
Properties
Almost nothing is known about the biological activities and phytochemistry of Allomorphia . Ellagitannins are commonly present, as is the case in many other Melastomataceae . A general phytochemical screening showed that A. bullata leaves and stems contain some alkaloids and terpenes but no saponins, but the presence of alkaloids could not be demonstrated for A. alata or A. exigua .
Botany
Shrubs or half-shrubby herbs, up to 3 m tall. Leaves opposite, those of a pair equal or slightly unequal, simple and entire, symmetrical, usually membranous, 3-5-veined, with coarsely reticulate fine veins; petiole usually long; stipules absent. Inflorescence a terminal panicle or raceme, with terminal branchlets 3-flowered. Flowers bisexual, 3-4-merous; calyx with cylindrical or obconical tube, toothed; petals inserted at the rim of the calyx limb, free, whitish or yellowish-green; stamens 6 or 8, equal or unequal in length, anthers equal or subequal in shape, without appendages, pinkish or purplish, opening by a single pore; ovary inferior, 3-4-celled, style filiform with minute stigma. Fruit a capsule, urceolate to subglobose, about as long as wide, 6-8-ribbed, dehiscing apically with minute valves, many-seeded. Seeds irregular, beaked.
Allomorphia is closely related to Oxyspora , and is reduced by some authors to a synonym of the last genus. In general, Allomorphia has smaller inflorescences and flowers, equal or subequal anthers without appendages (in Oxyspora dimorphic anthers with appendages), and smaller urceolate or subglobose fruits (in Oxyspora ellipsoid or obconical).
Ecology
Allomorphia occurs particularly in the undergrowth of lowland forest, sometimes also in abandoned plantations near the forest. The species treated here are locally common in Peninsular Malaysia.
Management Allomorphia can be grown in gardens under partial shade. For this purpose, seed is sometimes collected from wild plants.
Genetic resources
Not much is known about the exact distribution of Allomorphia species, but those treated here seem locally common and not particularly endangered.
Prospects
Research on properties and phytochemistry is needed in order to evaluate the properties and prospects of Allomorphia as medicinal plants. Moreover, a thorough taxonomical study of the genus and related genera is badly needed.
Literature
121, 282, 331, 707, 731.
Selection of species
Authors
H.C. Ong
