''Pseuduvaria hylandii'' 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

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

. L.W. Jessup, the botanists who first formally described the species, named it after

Bernard Hyland Bernard Hyland (Bernard Patrick Matthew Hyland, born 1937), known as Bernie Hyland, is an Australian botanist. He has contributed significantly to the understanding of Australian plants, in particular numerous species of his home and workplace ...

an Australian botanist who collected the specimen he examined.

Description

It is a tree reaching 13 meters in height. The young, dark brown to black branches are sparsely covered in hairs and also have many

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, membranous to papery leaves are 13-24 by 3-6.5 centimeters. The leaves have pointed to wedge-shaped bases and tapering tips, with the tapering portion 8-18 millimeters long. The leaves are hairless on their upper and lower surfaces. The leaves have 8-12 pairs of secondary veins emanating from their midribs. Its hairless petioles are 5-13 by 1.5-3 millimeters with a narrow 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 groups of 2-3 on branches, and are organized on indistinct peduncles. Each inflorescence has a solitary flower. Each flower is on a 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 4-12 by 0.5-1 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 3-6

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, slightly 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 1.5-3 by 3-3.5 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 cream-colored to slightly pink, oval to elliptical, outer petals are 3.5-5.5 by 4-5 millimeters with hairless upper surfaces and very densely hairy lower surfaces. The inner petals are maroon with purple highlights at their edges. The diamond-shaped, inner petals have a 5-7 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 10.5-14.5 by 5.5-7 millimeter blade. The inner petals have pointed bases and tips. The inner petals are sparsely to densely hairy on their upper surface and densely hairy on their lower surfaces. The inner petals have two, irregularly shaped, smooth, raised glands on their upper surface. Male flowers have up to 67

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 1-2 by 0.9-1 millimeters. Female flowers have 23-29

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 1.5-2.3 by 0.6-1 millimeters. Each carpel has 1-3

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 fruit occur in clusters of 12-16 on slightly hairy pedicles that are 11-16 by 1.5-2.5 millimeters. The orange, mature fruit are elliptical to egg-shaped and 9-17 by 7-12 millimeters. The fruit are smooth, and sparsely to densely hairy. Each fruit has up to 2 spherical seeds that are 8-10 by 7.5-8.5 by 4.5-6.5 millimeters. The seeds are very wrinkly.

Reproductive biology

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

Habitat and distribution

It has been observed growing in rocky and clay soils in vine forests at elevations of 400-780 meters.

Uses

Oils extracted from its leaves contain high levels of

caryophyllene Caryophyllene (), more formally (−)-β-caryophyllene, (BCP), is a natural bicyclic sesquiterpene that is a constituent of many essential oils, especially clove oil, the oil from the stems and flowers of '' Syzygium aromaticum'' (cloves), the ess ...

and

humulene Humulene, also known as α-humulene or α-caryophyllene, is a naturally occurring monocyclic sesquiterpene (C15H24), containing an 11-membered ring and consisting of 3 isoprene units containing three nonconjugated C=C double bonds, two of them be ...

References

{{Taxonbar, from=Q17135143 hylandii Flora of Queensland Endemic flora of Australia Plants described in 1987