''Duckeanthus'' is a genus of

plant Plants are the eukaryotes that form the Kingdom (biology), kingdom Plantae; they are predominantly Photosynthesis, photosynthetic. This means that they obtain their energy from sunlight, using chloroplasts derived from endosymbiosis with c ...

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

Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...

. It contains a single species, ''Duckeanthus grandiflorus''. Robert Elias Fries, the Swedish botanist who first formally described it, named it in honor of

Adolpho Ducke Adolpho Ducke (October 19, 1876 – January 5, 1959), (also referred to as Adolfo Ducke and occasionally misspelled "Duque"), was a notable entomologist, botanist and ethnographer specializing in Amazonia. According to family records, he was an ...

who collected the specimen he examined, and its large (''grandis'' in Latin) flowers.

Description

It is a small tree. Its mature branches are smooth. Its

internodes A stem is one of two main structural axes of a vascular plant, the other being the root. It supports leaves, flowers and fruits, transports water and dissolved substances between the roots and the shoots in the xylem and phloem, engages in pho ...

are 3–5 centimeters long. Its hairless petioles are 5–7 millimeters long and 3 millimeters thick and have a deep groove on their upper surfaces. Its papery, elliptical leaves are 19–23 by 7.5–10.5 centimeters. The leaves have bright green hairless upper surfaces and yellow-green hairless lower surfaces. The tips of the leaves come to an abrupt tapering point about 2 centimeters long. Its leaves have about 10 secondary veins emanating from either side of their midribs. The secondary veins arch toward the leaf tip and join one another 4–6 millimeters before reaching the margin of the leaf. Its inflorescences have 1–2 flowers and are emerge from extra-

axillary Axillary means "related to the axilla (armpit)" or "related to the leaf axils". "Axillary" may refer to: Biology * Axillary artery * Axillary border * Axillary fascia * Axillary feathers * Axillary hairs * Axillary lines * Axillary lymph nodes ...

positions. Its white flowers are on 2 centimeter long, erect, hairless, warty

pedicels In botany, a pedicel is a stem that attaches a single flower to the inflorescence In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branch ...

. The pedicels have a 2 millimeter long

bract In botany, a bract is a modified or specialized leaf, associated with a reproductive structure such as a flower, inflorescence axis or cone scale. Bracts are usually different from foliage leaves in size, color, shape or texture. They also lo ...

at their base and about halfway up their length. Its round to triangular

sepal 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 Etymology The term ''sepalum'' ...

s are 15 by 15 millimeters and come to a point at their tip. The sepals are hairless on both sides, but are often warty. It has 6 fleshy petals in two rows of 3. Its outer petals are 3 by 2 centimeters, have silky hairs on their inner surfaces, and come to a shallow point at their tip. Its rhomboidal to oval inner petals are 4.5–5 by 2.5–3 centimeters and covered in sparse hairs. Its 2.5-3 millimeter long

stamen The stamen (: stamina or stamens) is a part consisting of the male reproductive organs of a flower. Collectively, the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filament ...

s form an androecium 1.5 centimeters in diameter. The connective tissue between the lobes of

anthers The stamen (: stamina or stamens) is a part consisting of the male reproductive organs of a flower. Collectively, the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filamen ...

is overgrown to form a flat cap covered in short hairs. Its narrow, oval

ovaries The ovary () is a gonad in the female reproductive system that produces ova; when released, an ovum travels through the fallopian tube/oviduct into the uterus. There is an ovary on the left and the right side of the body. The ovaries are endocr ...

are 1.5 millimeters long and covered in rust-colored hairs. Its bristly stigmas are 1.5 millimeters long.

Reproductive biology

The orange pollen of ''D. grandiflorus'' is shed as permanent tetrads.

Habitat and distribution

It has been observed growing in wet forest habitats.

References

{{Taxonbar, from1=Q15961892, from2=Q8770902 Flora of Brazil Plants described in 1934 Monotypic Magnoliales genera Annonaceae Annonaceae genera Taxa named by Robert Elias Fries