''Pseuduvaria luzonensis'' 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 The Annonaceae are a Family (biology), family of flowering plants consisting of trees, shrubs, or rarely lianas commonly known as the custard apple family or soursop family. With 108 accepted genera and about 2400 known species, it is the largest ...

. It is native to The

Philippines The Philippines (; fil, Pilipinas, links=no), officially the Republic of the Philippines ( fil, Republika ng Pilipinas, links=no), * bik, Republika kan Filipinas * ceb, Republika sa Pilipinas * cbk, República de Filipinas * hil, Republ ...

Elmer Drew Merrill Elmer Drew Merrill (October 15, 1876 – February 25, 1956) was an American botanist and taxonomist. He spent more than twenty years in the Philippines where he became a recognized authority on the flora of the Asia-Pacific region. Through t ...

, the American botanist who first formally described the species using the synonym ''Orophea luzoniensis'', named it after

Luzon Luzon (; ) is the largest and most populous island in the Philippines. Located in the northern portion of the Philippines archipelago, it is the economic and political center of the nation, being home to the country's capital city, Manila, as ...

in the Province of Battan, Philippines where the specimen he examined was collected along the Lamao River.

Description

It is a tree reaching 10 meters in height. The young, yellow-brown to black branches are densely hairy, but become hairless when mature. The branches 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 elliptical, papery to leathery leaves are 10-27 by 3–8.5 centimeters. The leaves have pointed to wedge-shaped bases and tapering tips, with the tapering portion 5-19 millimeters long. The leaves are hairless on their upper surfaces and sparsely hairy on their lower surfaces. The leaves have 10-18 pairs of secondary veins emanating from their midribs. Its very densely hairy petioles are 4-12 by 1-3 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 alone or in pairs 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 12-30 by 0.3-0.8 millimeters. The pedicels are organized on a

rachis In biology, a rachis (from the grc, ῥάχις [], "backbone, spine") is a main axis or "shaft". In zoology and microbiology In vertebrates, ''rachis'' can refer to the series of articulated vertebrae, which encase the spinal cord. In this c ...

up to 5 millimeters long that have 2-3

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 0.5-1.5 millimeters long. Its flowers are unisexual. Its flowers have 3 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 1.5-2.5 by 1.5-2.5 millimeters. The sepals are hairless on their upper surface, very densely hairy on their lower surface, and hairy at their margins. Its 6 petals are arranged in two rows of 3. The greenish-white, circular, outer petals are 2.5-4.5 by 2–3.5 millimeters with hairless upper surfaces and very densely hairy lower surfaces. The inner petals are greenish-white to yellowish-green. The diamond-shaped, inner petals have a 7-14 millimeter long

claw A claw is a curved, pointed appendage found at the end of a toe or finger in most amniotes (mammals, reptiles, birds). Some invertebrates such as beetles and spiders have somewhat similar fine, hooked structures at the end of the leg or tarsus ...

at their base and a 11-20 by 7-12 millimeter blade. The inner petals have pointed bases and pointed to tapering tips. The inner petals are hairless on their upper surface except near their tips, and densely hairy on their lower surfaces. Male flowers have 70-85

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 0.6-1 by 0.5-0.8 millimeters. Female flowers have 13-14

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 2-2.5 by 0.7-1 millimeters. Each carpel has 4-6

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 arranged in a row. The female flowers have 2-7 sterile stamens. The fruit occur in clusters of up to 3 on slightly hairy pedicles that are 16-18 by 1 millimeters. The yellow-green fruit are elliptical and 6-7 by 4 millimeters. The fruit are smooth, and very densely hairy.

Reproductive biology

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

Habitat and distribution

It has been observed growing in lowland forests at elevations of 90–100 meters.

References

{{Taxonbar, from=Q17135044 luzonensis Flora of the Philippines Plants described in 1908 Taxa named by Elmer Drew Merrill Taxobox binomials not recognized by IUCN