Ampelocissus xizangensis
Encyclopedia
Ampelocissus xizangensis (xi zang suan lian teng in Chinese) is a deciduous
Deciduous
Deciduous means "falling off at maturity" or "tending to fall off", and is typically used in reference to trees or shrubs that lose their leaves seasonally, and to the shedding of other plant structures such as petals after flowering or fruit when ripe...

 vine
Vine
A vine in the narrowest sense is the grapevine , but more generally it can refer to any plant with a growth habit of trailing or scandent, that is to say climbing, stems or runners...

 in the Vitaceae
Vitaceae
Vitaceae are a family of dicotyledonous flowering plants including the grapevine and Virginia creeper. The family name is derived from the genus Vitis...

 family, native to shrubland
Shrubland
Shrubland, scrubland, scrub or brush is a plant community characterized by vegetation dominated by shrubs, often also including grasses, herbs, and geophytes. Shrubland may either occur naturally or be the result of human activity...

s in the high valleys of the Tibet Autonomous Region
Tibet Autonomous Region
The Tibet Autonomous Region , Tibet or Xizang for short, also called the Xizang Autonomous Region is a province-level autonomous region of the People's Republic of China , created in 1965....

 and Nepal
Nepal
Nepal , officially the Federal Democratic Republic of Nepal, is a landlocked sovereign state located in South Asia. It is located in the Himalayas and bordered to the north by the People's Republic of China, and to the south, east, and west by the Republic of India...

, at elevations about 2000 m high.

Its specific epithet is a toponym derived from the place it was collected from, Xizang, which is the Chinese name for the Tibet Autonomous Region. It was first scientifically described in 1997 by the Chinese
Chinese people
The term Chinese people may refer to any of the following:*People with Han Chinese ethnicity ....

 botanist, Li Chao-Luang.

Branches and tendrils

The liana
Liana
A liana is any of various long-stemmed, woody vines that are rooted in the soil at ground level and use trees, as well as other means of vertical support, to climb up to the canopy to get access to well-lit areas of the forest. Lianas are especially characteristic of tropical moist deciduous...

s of A. xizangensis are woody. Its climbing branchlet
Branch
A branch or tree branch is a woody structural member connected to but not part of the central trunk of a tree...

s, which are cylindrical and gradually tapering, have longitudinal ridges and sometimes a slight, pale wooliness.

Dividing off from them are characteristicly bifurcated tendrils, which appear as twisting cork-screws. These grow towards and slowly grip whatever tall, stationary object they happen upon. This action, called circumnutation
Nutation in plants
Nutation, in plants, is the bending movements executed by some plant organs, such as stems, leaves, roots, etc., by which the part is inclined successively in various directions. Nutations are due to the unequal rate of growth of different sides of the organ, an inequality which, so far as is known...

, has the real effect of securing and pulling the branches higher, thus enabling its leaves exposure to the sun for photosynthesis
Photosynthesis
Photosynthesis is a chemical process that converts carbon dioxide into organic compounds, especially sugars, using the energy from sunlight. Photosynthesis occurs in plants, algae, and many species of bacteria, but not in archaea. Photosynthetic organisms are called photoautotrophs, since they can...

. The whole process is repeated continuously throughout the life-cycle of the plant.

Foliage

The leaves
Leaf
A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....

 of A. xizangensis are simple. leaflet
Leaflet
A leaflet in botany is a part of a compound leaf. A leaflet may resemble an entire leaf, but it is not borne on a stem as a leaf is, but rather on a vein of the whole leaf. Compound leaves are common in many plant families...

s are typically between 23 - 24 cm long, broadly ovate, cordate at their bases, rounded and obtuse at their apexes, and finely-toothed on their margins. Each has 5 basal veins, and 4 or 5 pairs of lateral veins. Smaller veins are barely noticeable on the leaf's upper (adaxial) surface, while being slightly prominent on the under (abaxial) side. They are intricately downy with brown tomentum adaxially, and covered in somewhat long and straight, slightly stiff but weak, hair
Trichome
Trichomes are fine outgrowths or appendages on plants and certain protists. These are of diverse structure and function. Examples are hairs, glandular hairs, scales, and papillae.- Algal trichomes :...

s abaxially. The petiole
Petiole (botany)
In botany, the petiole is the stalk attaching the leaf blade to the stem. The petiole usually has the same internal structure as the stem. Outgrowths appearing on each side of the petiole are called stipules. Leaves lacking a petiole are called sessile, or clasping when they partly surround the...

 is about 15 cm long, and only covered sparsely in brownish, arachnoid hairs, which tend to be shed over time.

Flowers

The flower
Flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...

 bud
Bud
In botany, a bud is an undeveloped or embryonic shoot and normally occurs in the axil of a leaf or at the tip of the stem. Once formed, a bud may remain for some time in a dormant condition, or it may form a shoot immediately. Buds may be specialized to develop flowers or short shoots, or may have...

s of A. xizangensis emerge elliptic, with a rounded apex, and measure 2 to 2.5 mm in length, blooming in July.

    


Inflorescence
Inflorescence
An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...

s are leaf-opposed, compound dichasiums (at left). The inflorescence's base branches into two peduncle
Peduncle (botany)
In botany, a peduncle is a stem supporting an inflorescence, or after fecundation, an infructescence.The peduncle is a stem, usually green and without leaves, though sometimes colored or supporting small leaves...

s before terminating in a tendril. The peduncles, which are about 6 cm long, branch into pedicel
Pedicel (botany)
A pedicel is a stem that attaches single flowers to the main stem of the inflorescence. It is the branches or stalks that hold each flower in an inflorescence that contains more than one flower....

s, and are, like the petioles of the leaves, sparsely matted in arachnoid tomentum; but unlike the petioles, these tend not to be shed.

The pedicel, which is 1-1.5 mm long, wears a sparse coat of glandular hairs
Trichome
Trichomes are fine outgrowths or appendages on plants and certain protists. These are of diverse structure and function. Examples are hairs, glandular hairs, scales, and papillae.- Algal trichomes :...

. The calyx is nearly hairless, has pendulous lobes and is generally saucer
Saucer
A saucer is a small type of dishware, a plate that is specifically used with and for supporting a cup – a cylindrical cup intended for coffee or a half-sphere teacup for tea. Additionally, the saucer is a distant cousin to the plate. The saucer has a raised centre with a depression sized to fit a...

-like in shape. Petal
Petal
Petals are modified leaves that surround the reproductive parts of flowers. They often are brightly colored or unusually shaped to attract pollinators. Together, all of the petals of a flower are called a corolla. Petals are usually accompanied by another set of special leaves called sepals lying...

s are smooth, ovate-oblong, and measure 1.5-1.8 mm. There are 5 stamen
Stamen
The stamen is the pollen producing reproductive organ of a flower...

s, each topped by an oval anther. The lower portion of the ovary is adnate
Adnation
Adnation in plants is the "union of unlike parts; organically united or fused with another dissimilar part, e.g. an ovary to a calyx tube, or stamens to petals". This is in contrast to connation, the fusion of similar organs....

 to the flower's disk, which is lobed and clearly visible. The style
Gynoecium
Gynoecium is most commonly used as a collective term for all carpels in a flower. A carpel is the ovule and seed producing reproductive organ in flowering plants. Carpels are derived from ovule-bearing leaves which evolved to form a closed structure containing the ovules...

 is short with ridges, about ten in number.

Fruit

The fruit
Fruit
In broad terms, a fruit is a structure of a plant that contains its seeds.The term has different meanings dependent on context. In non-technical usage, such as food preparation, fruit normally means the fleshy seed-associated structures of certain plants that are sweet and edible in the raw state,...

 of A. xizangensis is a one- to four-seeded
Seed
A seed is a small embryonic plant enclosed in a covering called the seed coat, usually with some stored food. It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth within the mother plant...

, grape
Grape
A grape is a non-climacteric fruit, specifically a berry, that grows on the perennial and deciduous woody vines of the genus Vitis. Grapes can be eaten raw or they can be used for making jam, juice, jelly, vinegar, wine, grape seed extracts, raisins, molasses and grape seed oil. Grapes are also...

-like berry
Berry
The botanical definition of a berry is a fleshy fruit produced from a single ovary. Grapes are an example. The berry is the most common type of fleshy fruit in which the entire ovary wall ripens into an edible pericarp. They may have one or more carpels with a thin covering and fleshy interiors....

.
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