Mastixia

Mastixia arborea

The plant genus Mastixia belongs to the family of Dogwood ( Cornaceae ). The distribution area of ​​about 25 species Asia and Malaysia's.

Description

Vegetative characteristics

In Mastixia types are resin- producing, evergreen trees. The branches are terete or provided with longitudinal strips.

The opposite or alternate arranged on the branches leaves are stalked. The leathery or thick paper-like, simple leaf blades are oblong - elliptic, ovate or narrowly obovate. Stipules absent.

Generative features

The inflorescences are terminal or pendant. The flowers are on stalks about two bracts.

The hermaphrodite flowers are radial symmetry, usually four or fünfzählig double perianth. The usually four or five, rarely up to seven thick sepals are bell-shaped adherent and durable. The usually four or five, rarely six free petals are coriaceous, ovate and have a bent- tip. In the flower bud, the petals touch, but without overlap ( valvat ). The number of stamens varies depending on the type of four, five, six or eight. The short stamens are subulate and flattened. The pollen grains have three apertures. It's just a constant under carpel available. The carpel contains only one hanging ovule. The often until fruit ripening durable, short stylus is conical and terminates in a point, or ungelappten easier with two, four, or five-lobed stigma. The carpel is surrounded by an annular, fleshy disc, which is often easily four or five lobes.

The bluish- purple when ripe, ovate, oblong- ovate or narrow spherical drupes are fleshy or if they are dry hard. The stone core has a woody, längsgerieftes endocarp. The seed coat is white and membranous. The seed has a fleshy endosperm and a small embryo with two foliage leaf-like cotyledons ( cotyledons ).

The chromosome numbers be 2n = 22, 26

Dissemination and Fossil evidence

The approximately 25 species are extant in India, Sri Lanka, Bhutan, Cambodia, Laos, Malaysia, Myanmar, China, Vietnam, Thailand, Indonesia, Papua New Guinea, the Philippines and the Solomon Islands before.

Crop residues and leaf imprints that are assigned to the genus fossil Mastixia are relatively frequent. The earliest examples date back to the Eocene. The genus was widespread in Europe and North America during the Eocene and Oligocene. This genus therefore used to have a wider distribution.

System

The first description of the genus Mastixia in 1826 by Carl Ludwig Blume in the Bijdragen tot de flora van Nederlandsch Indië, Volume 13, pp. 654

The taxonomic classification of the genus Mastixia has long been debated. It was occasionally made ​​to the family Nyssaceae, which is attributed to their part today in the rank of a subfamily Nyssoideae the Cornaceae family (APG III). Other authors saw Mastixia together with the genus Diplopanax that are characterized by the possession of ten stamens - is different and constant five petals of the former, as an independent family Mastixiaceae to - five staminodial.

The genus contains about 25 species Mastixia (selection):

• Mastixia arborea ( Wight ) C.B.Clarke
• Mastixia caudatilimba CYWu ex Soong: This endemic species grows in subtropical forests and moderately humid forests in valleys at altitudes 1400-1600 meters only in Xishuangbanna: Nannuo Shan in southern Yunnan.
• Mastixia congylos Kosterm.
• Mastixia cuspidata flower
• Mastixia eugenioides K.M.Matthew
• Mastixia euonymoides Prain
• Mastixia glauca K.M.Matthew
• Mastixia kaniensis Melch.
• Mastixia macrocarpa K.M.Matthew
• Mastixia montana Kosterm.
• Mastixia nimalii Kosterm.
• Mastixia octandra K.M.Matthew
• Mastixia parviflora H.Zhu
• Mastixia pentandra flower: It occurs in Cambodia, China, northeastern India, Malaysia, Myanmar, Thailand and Vietnam.
• Mastixia rostrata flower
• Mastixia tetrandra ( Wight ex Thwaites ) C.B.Clarke
• Mastixia tetrapetala Merr.
• Mastixia trichophylla WPFang ex Soong: It is an endemic species in evergreen rain forests to elevations of about 700 meters in the southern Guangxi.
• Mastixia trichotoma flower