Dransfieldia
Encyclopedia
Dransfieldia is a monotypic genus
of flowering plant
in the palm
family from New Guinea
where the lone species Dransfieldia micrantha grows in dense rain forest. Discovered in 1872, 134 years passed before DNA
testing revealed its proper placement. With no close relatives, it is a delicate, pinnate-leaved palm named for John Dransfield
, former palm expert at the Kew Royal Botanic Gardens
.
; the small rachis bears widely-spaced, acute leaflets, slightly offset and taper to a point. The inflorescence
is borne beneath the crownshaft, protected by a caducous prohyll, once-branched, producing one-seed
ed fruit
with apical remains.
first collected the palm in Indonesian New Guinea in 1872 assigning it to the Ptychosperma
genus under the epithet micranthum, Latin
for "small flower". The leaf tips were not jagged like most in the genus and, eleven years later, was moved to Rhopaloblaste
by Sir Joseph Hooker
, then director of the Kew gardens. The fit was imperfect as the male flowers and seedling eophylls in Rhopaloblaste did not match. In 1970, palm scientist Harold E. Moore
analyzed Beccari's collection, and despite bearing a crownshaft, reclassified it as a member of Heterospathe
, a non-crownshafted genus. Finally, in 2006, DNA tests revealed the plant matched no known genera; it was named for John Dransfield by his contemporaries to honor his long study of the family.
, with high humidity
and frequent rainfall.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of flowering plant
Flowering plant
The flowering plants , also known as Angiospermae or Magnoliophyta, are the most diverse group of land plants. Angiosperms are seed-producing plants like the gymnosperms and can be distinguished from the gymnosperms by a series of synapomorphies...
in the palm
Arecaceae
Arecaceae or Palmae , are a family of flowering plants, the only family in the monocot order Arecales. There are roughly 202 currently known genera with around 2600 species, most of which are restricted to tropical, subtropical, and warm temperate climates...
family from New Guinea
New Guinea
New Guinea is the world's second largest island, after Greenland, covering a land area of 786,000 km2. Located in the southwest Pacific Ocean, it lies geographically to the east of the Malay Archipelago, with which it is sometimes included as part of a greater Indo-Australian Archipelago...
where the lone species Dransfieldia micrantha grows in dense rain forest. Discovered in 1872, 134 years passed before DNA
DNA
Deoxyribonucleic acid is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms . The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in...
testing revealed its proper placement. With no close relatives, it is a delicate, pinnate-leaved palm named for John Dransfield
John Dransfield
John Dransfield is an honorary research fellow and former head of palm research at the Royal Botanic Gardens, Kew, United Kingdom, as well as being an authority on the phylogenetic classification of palms....
, former palm expert at the Kew Royal Botanic Gardens
Royal Botanic Gardens, Kew
The Royal Botanic Gardens, Kew, usually referred to as Kew Gardens, is 121 hectares of gardens and botanical glasshouses between Richmond and Kew in southwest London, England. "The Royal Botanic Gardens, Kew" and the brand name "Kew" are also used as umbrella terms for the institution that runs...
.
Description
The thin trunk is solitary, gray to maroon in color, with distinct, widely-spaced leaf scar rings. The leaf sheaths are extended, forming a distinct green crownshaftCrownshaft
An elongated circumferential leaf base formation present on some species of palm is called a crownshaft.The leaf bases of some pinnate leaved palms form a sheath at the top of the trunk surrounding the bud where all the subsequent leaves are formed.The crownshaft...
; the small rachis bears widely-spaced, acute leaflets, slightly offset and taper to a point. The inflorescence
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. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...
is borne beneath the crownshaft, protected by a caducous prohyll, once-branched, producing one-seed
Seed
A seed is a small embryonic plant enclosed in a covering called the seed coat, usually with some stored food. It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth within the mother plant...
ed fruit
Fruit
In broad terms, a fruit is a structure of a plant that contains its seeds.The term has different meanings dependent on context. In non-technical usage, such as food preparation, fruit normally means the fleshy seed-associated structures of certain plants that are sweet and edible in the raw state,...
with apical remains.
Taxonomy
Odoardo BeccariOdoardo Beccari
Odoardo Beccari was an Italian naturalist perhaps best known for discovering the titan arum, the plant with the largest unbranched inflorescence in the world, in Sumatra in 1878...
first collected the palm in Indonesian New Guinea in 1872 assigning it to the Ptychosperma
Ptychosperma
Ptychosperma is a genus of flowering plant in the Arecaceae family. Most are native to Australia and/or New Guinea, but some have been cultivated abroad as house or garden plants.It contains the following species:*Ptychosperma burretianum...
genus under the epithet micranthum, Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
for "small flower". The leaf tips were not jagged like most in the genus and, eleven years later, was moved to Rhopaloblaste
Rhopaloblaste
Rhopaloblaste is a genus of flowering plant in the Arecaceae family.It contains the following species:* Rhopaloblaste augusta* Rhopaloblaste elegans* Rhopaloblaste singaporensis...
by Sir Joseph Hooker
Joseph Dalton Hooker
Sir Joseph Dalton Hooker OM, GCSI, CB, MD, FRS was one of the greatest British botanists and explorers of the 19th century. Hooker was a founder of geographical botany, and Charles Darwin's closest friend...
, then director of the Kew gardens. The fit was imperfect as the male flowers and seedling eophylls in Rhopaloblaste did not match. In 1970, palm scientist Harold E. Moore
Harold E. Moore
Harold Emery Moore, Jr. was an American botanist especially known for his work on the systematics of the palm family. He served as Director of the L. H. Bailey Hortorium at Cornell University, and was appointed Liberty Hyde Bailey Professor of Botany in 1978...
analyzed Beccari's collection, and despite bearing a crownshaft, reclassified it as a member of Heterospathe
Heterospathe
Heterospathe is a monoecious genus of flowering plant in the palm family found in Oceania where it is called sagisi palm. Among members of the Iguanurinae it is described as relatively unspecialized...
, a non-crownshafted genus. Finally, in 2006, DNA tests revealed the plant matched no known genera; it was named for John Dransfield by his contemporaries to honor his long study of the family.
Distribution and habitat
They are restricted to western New Guinea rain forest undergrowthUndergrowth
Undergrowth usually refers to the vegetation in a forest, which can obstruct passage through the forest. The height of undergrowth is usually considered to be 0.3 – 3 m . Undergrowth can also refer all vegetation in a forest, which isn't in the canopy....
, with high humidity
Humidity
Humidity is a term for the amount of water vapor in the air, and can refer to any one of several measurements of humidity. Formally, humid air is not "moist air" but a mixture of water vapor and other constituents of air, and humidity is defined in terms of the water content of this mixture,...
and frequent rainfall.