''Pseuduvaria parvipetala'' is a species of

plant Plants are predominantly photosynthetic eukaryotes of the kingdom Plantae. Historically, the plant kingdom encompassed all living things that were not animals, and included algae and fungi; however, all current definitions of Plantae exclud ...

in the family Annonaceae. It is native to

Borneo Borneo (; id, Kalimantan) is the third-largest island in the world and the largest in Asia. At the geographic centre of Maritime Southeast Asia, in relation to major Indonesian islands, it is located north of Java, west of Sulawesi, and eas ...

and

Sumatra Sumatra is one of the Sunda Islands of western Indonesia. It is the largest island that is fully within Indonesian territory, as well as the sixth-largest island in the world at 473,481 km2 (182,812 mi.2), not including adjacent i ...

. Yvonne Su and Richard Saunders, the botanists who first formally described the species, named it after its small (, in Latin) petals (, in Latin).

Description

It is a tree reaching 10 meters in height. The young, light to dark brown branches are sparsely hairy and also have sparse

lenticel A lenticel is a porous tissue consisting of cells with large intercellular spaces in the periderm of the secondarily thickened organs and the bark of woody stems and roots of dicotyledonous flowering plants. It functions as a pore, providing a ...

s. Its egg-shaped to elliptical, papery to slightly leathery leaves are 8.5-17 by 3-6.5 centimeters. The leaves have pointed bases and tapering tips, with the tapering portion 12-22 millimeters long. The leaves are hairless on their upper and lower surfaces. The leaves have 10-14 pairs of secondary veins emanating from their midribs. Its sparsely to densely hairy petioles are 4-10 by 1-2 millimeters with a broad groove on their upper side. Its

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. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed o ...

s occur in pairs on branches, and are organized on slightly to sparsely hairy peduncles that are 1.5-3 millimeters. Each inflorescence has up to 18 flowers. Each flower is on a slightly to sparsely hairy

pedicel Pedicle or pedicel may refer to: Human anatomy *Pedicle of vertebral arch, the segment between the transverse process and the vertebral body, and is often used as a radiographic marker and entry point in vertebroplasty and kyphoplasty procedures ...

that is 3-9 by 0.2-0.5 millimeters. The pedicels are organized on a rachis up to 5 millimeters long that have 3-18

bract In botany, a bract is a modified or specialized leaf, especially one associated with a reproductive structure such as a flower, inflorescence axis or cone scale. Bracts are usually different from foliage leaves. They may be smaller, larger, or of ...

s. The pedicels have a medial, densely hairy

that is 0.5-1 millimeters long. Its flowers are unisexual. Its flowers have 3 free, triangular

sepals A sepal () is a part of the flower of angiosperms (flowering plants). Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom., p. 106 The term ''sepalum'' was coined b ...

, that are 0.7-1 by 1-1.5 millimeters. The sepals are hairless on their upper surface, sparsely to densely hairy on their lower surface, and hairy at their margins. Its 6 petals are arranged in two rows of 3. The pale yellow to pink, oval, outer petals are 1.5-2 by 1-2 millimeters with hairless upper and sparsely hairy lower surfaces. The pale yellow to pink, triangular, inner petals have a 1-2 millimeter long claw at their base and a 2-3.5 by 1.5-2.5 millimeter blade. The inner petals have flat bases and pointed tips. The inner petals are slightly hairy on their upper and lower surfaces. The inner petals have a single, smooth, flat, sausage-shaped gland on their upper surface. Male flowers have up to 26

stamen The stamen (plural ''stamina'' or ''stamens'') is the pollen-producing reproductive organ of a flower. Collectively the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filame ...

s that are 0.6 by 0.5-0.6 millimeters. Female flowers have up to 5

carpels Gynoecium (; ) is most commonly used as a collective term for the parts of a flower that produce ovules and ultimately develop into the fruit and seeds. The gynoecium is the innermost whorl of a flower; it consists of (one or more) ''pistils'' ...

that are 1 by 0.5 millimeters. Each carpel has 2

ovule In seed plants, the ovule is the structure that gives rise to and contains the female reproductive cells. It consists of three parts: the ''integument'', forming its outer layer, the ''nucellus'' (or remnant of the megasporangium), and the fe ...

s. The fruit occur in pairs and are organized on a sparsely hairy peduncle that is 3 by 1 millimeters. The fruit are attached by sparsely hairy pedicles that are 15 by 1 millimeters. The globe-shaped fruit are 7-9 by 7-9 millimeters. The fruit are wrinkly, and densely hairy.

Reproductive biology

The pollen of ''P. parvipetala'' is shed as permanent tetrads.

Habitat and distribution

It has been observed growing in sandstone or clay soils in lowland forests or rocky outcrops at elevations of 100-230 meters.

References

{{Taxonbar, from=Q17135454 parvipetala Flora of Borneo Flora of Sumatra Plants described in 2006 Taxa named by Richard M.K. Saunders Taxa named by Yvonne Chuan Fang Su