''Pseuduvaria oxycarpa'' is a species of plant in the family Annonaceae. It is native to

Sulawesi Sulawesi (), also known as Celebes (), is an island in Indonesia. One of the four Greater Sunda Islands, and the world's eleventh-largest island, it is situated east of Borneo, west of the Maluku Islands, and south of Mindanao and the Sulu Ar ...

Sijfert Hendrik Koorders Sijfert Hendrik Koorders (1863 – 1919) was a Dutch botanist, who worked primarily on the flora of Java. Life Koorders was born in Bandung, Indonesia on 29 November 1863. In 1881 he graduated from the Hogere Burgerschool in Haarlem in the ...

, the Dutch botanist who first formally described the species, named it after the pointed (Latinized form of Greek , oxus) tips of its fruit (Latinized form of Greek , karpos).

Description

It is a tree reaching 13 meters in height. The young, yellow-brown to dark brown branches are slightly hairy. Its elliptical, papery leaves are 18–43.5 by 7.5-15 centimeters. The leaves have blunt bases and tapering tips, with the tapering portion 12–17 millimeters long. The leaves are hairless on their upper and lower surfaces. The leaves have 16–20 pairs of secondary veins emanating from their midribs. Its slightly hairy petioles are 9–15 by 2.5–4.5 millimeters with a broad groove on their upper side. Its inflorescences occur in groups of 2–5 on branches, and are organized on indistinct peduncles. Each inflorescence has 1–2 flowers. Each flower is on a very densely 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 14–20 by 0.6–1 millimeters. The pedicels are organized on a rachis up to 5 millimeters long that have up to 6

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, very densely hairy

that is 1.5–2 millimeters long. Its flowers are unisexual. Its flowers have 3 free, oval

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 1.5–2 by 2–3 millimeters. The sepals are hairless on their upper surface, densely hairy on their lower surface, and hairy at their margins. Its 6 petals are arranged in two rows of 3. The yellow, circular, outer petals are 5 by 4.5-5 millimeters with hairless upper and very densely hairy lower surfaces. The yellow, diamond-shaped inner petals have a 2-2.5 millimeter long claw at their base and a 5–6 by 3–4 millimeter blade. The inner petals have pointed bases and tips. The inner petals are densely hairy upper surfaces and very densely hairy lower surfaces. Male flowers have up to 65

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 0.7 by 0.5–0.6 millimeters. Female flowers have 6–9

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 2 by 1 millimeters. Each carpel has 3–4 ovules arranged in two rows. The fruit occur in clusters of 5–9 on slightly hairy pedicles that are 14–22 by 1.5–3.5 millimeters. The green, mature fruit are 13–22 by 7–18 millimeters. The fruit are globe shaped with an extended point. The fruit are wrinkly, and densely hairy. Each fruit has 3–4 lens-shaped seeds that are 11–13 by 7–8.5 by 5–6.5 millimeters. The seeds are wrinkly.

Reproductive biology

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

Habitat and distribution

It has been observed growing in clay volcanic soils in primary forests at elevations of 200–750 meters.

References

{{Taxonbar, from=Q17135381 oxycarpa Flora of Sulawesi Plants described in 1898 Taxa named by Sijfert Hendrik Koorders Taxa named by Yvonne Chuan Fang Su Taxa named by Richard M.K. Saunders