Banksia micrantha is a species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of shrub

Shrub

A shrub or bush is distinguished from a tree by its multiple stems and shorter height, usually under 5–6 m tall. A large number of plants may become either shrubs or trees, depending on the growing conditions they experience...

 in the plant

Plant

Plants are living organisms belonging to the kingdom Plantae. Precise definitions of the kingdom vary, but as the term is used here, plants include familiar organisms such as trees, flowers, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The group is also called green plants or...

 genus

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...

 Banksia

Banksia

Banksia is a genus of around 170 species in the plant family Proteaceae. These Australian wildflowers and popular garden plants are easily recognised by their characteristic flower spikes and fruiting "cones" and heads. When it comes to size, banksias range from prostrate woody shrubs to trees up...

. A small spreading bush with pale yellow flower spikes, it occurs between Eneabba

Eneabba, Western Australia

Eneabba is a town on the Brand Highway located 278 km north of Perth, Western Australia.The area is famous for its spectacular display of wildflowers in the spring. It is also home to the Iluka Resources mineral sands facility....

 and Cervantes

Cervantes, Western Australia

Cervantes is a town in Western Australia. The town is located just off Indian Ocean Drive about north north west of the state capital, Perth in the Shire of Dandaragan Local Government Area. At the 2006 census, Cervantes had a population of 503. The town was named after a ship that was wrecked...

 in South west

Southwest Australia

Southwest Australia is a biodiversity hotspot that includes the Mediterranean forests, woodlands, and scrub ecoregions of Western Australia. The region has a wet-winter, dry-summer Mediterranean climate, one of five such regions in the world...

 Western Australia

Western Australia

Western Australia is a state of Australia, occupying the entire western third of the Australian continent. It is bounded by the Indian Ocean to the north and west, the Great Australian Bight and Indian Ocean to the south, the Northern Territory to the north-east and South Australia to the south-east...

. First described by Alex George

Alex George

Alexander Segger George is a Western Australian botanist. He is the authority on the plant genera Banksia and Dryandra...

 in 1981, it is placed in Banksia section Oncostylis

Banksia sect. Oncostylis

Banksia sect. Oncostylis is one of four sections of subgenus Banksia subg. Banksia. It contains those Banksia species with hooked pistils. All of the species in Oncostylis also exhibit a top-down sequence of flower anthesis, except for Banksia nutans which is bottom-up.Banksia sect...

, series Abietinae

Banksia ser. Abietinae

Banksia ser. Abietinae is avalid botanic name for a series of Banksia. First published by Carl Meissner in 1856, the name has had three circumscriptions.-According to Meissner:...

.

Description

B. micrantha grows as a spreading bushy shrub up to 60 centimetres high and 120 centimetres wide. Leaves are very thin, being one to three centimetres long but less than 1.5 millimetres wide, with tightly revolute margins. Flowers occur in Banksias characteristic "flower spike", an 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...

 made up of hundreds of pairs of flowers densely packed in a spiral

Helix

A helix is a type of smooth space curve, i.e. a curve in three-dimensional space. It has the property that the tangent line at any point makes a constant angle with a fixed line called the axis. Examples of helixes are coil springs and the handrails of spiral staircases. A "filled-in" helix – for...

 round a woody axis. B. micranthas flower spike is a pale yellow colour, roughly spherical, around 4 centimetres in diameter. The fruiting structure is a stout woody "cone" embedded with up to 25 follicles

Follicle (fruit)

In botany, a follicle is a dry unilocular many-seeded fruit formed from one carpel and dehiscing by the ventral suture in order to release seeds, such as in larkspur, magnolia, banksia, peony and milkweed....

, which open to release the seed after bushfire.

Taxonomy

Banksia micrantha had been recorded since 1938, but considered part of a broad B. sphaerocarpa

Banksia sphaerocarpa

Banksia sphaerocarpa, commonly known as the Fox Banksia or Round-fruit Banksia, is a species of shrub or tree in the plant genus Banksia . It is generally encountered as a 1–2 m high shrub, and is usually smaller in the north of its range...

 complex, until officially described by Alex George in his classic monograph The genus Banksia L.f. (Proteaceae)

The genus Banksia L.f. (Proteaceae)

The genus Banksia L.f. is a 1981 monograph by Alex George on the taxonomy of the plant genus Banksia. Published by the Western Australian Herbarium as Nuytsia 3, it presented George's taxonomic arrangement of Banksia, the first major taxonomic revision of the genus since George Bentham published...

, B. micrantha is placed in Banksia subgenus Banksia

Banksia subg. Banksia

Banksia subg. Banksia is a valid botanic name for a subgenus of Banksia. As an autonym, it necessarily contains the type species of Banksia, B. serrata . Within this constraint, however, there have been various circumscriptions.-Banksia verae:B. subg...

 because its inflorescence is a characteristic Banksia flower spike; section Oncostylis

Banksia sect. Oncostylis

Banksia sect. Oncostylis is one of four sections of subgenus Banksia subg. Banksia. It contains those Banksia species with hooked pistils. All of the species in Oncostylis also exhibit a top-down sequence of flower anthesis, except for Banksia nutans which is bottom-up.Banksia sect...

 because its flowers have hooked styles; and series Abietinae

Banksia ser. Abietinae

Banksia ser. Abietinae is avalid botanic name for a series of Banksia. First published by Carl Meissner in 1856, the name has had three circumscriptions.-According to Meissner:...

 because of its roughly spherical flower spike. Its closest relative is said to B. sphaerocarpa (Fox Banksia). A 1996 cladistic analysis

Cladistics

Cladistics is a method of classifying species of organisms into groups called clades, which consist of an ancestor organism and all its descendants . For example, birds, dinosaurs, crocodiles, and all descendants of their most recent common ancestor form a clade...

 of Banksia by Kevin Thiele

Kevin Thiele

Kevin R. Thiele is curator of the Western Australian Herbarium. His research interests include the systematics of the plant families Proteaceae, Rhamnaceae and Violaceae, and the conservation ecology of grassy woodland ecosystems...

 and Pauline Ladiges confirmed B. micranthas placement in series Abietinae alongside B. sphaerocarpa, finding B. micrantha to be more closely related to B. sphaerocarpa var. sphaerocarpa and B. sphaerocarpa var. caesia than is B. sphaerocarpa var. dolichostyla. As a result, this last variety was upgraded to species rank as B. dolichostyla, and the four taxa were placed with B. grossa

Banksia grossa

Banksia grossa, commonly known as Coarse Banksia is a species of shrub in the plant family Proteaceae endemic to south west Western Australia. One of fourteen species of banksia with predominantly round or oval inflorescences of the series Abietinae, it was described in 1981 as a distinct species...

 in a new subseries of Abietinae, Banksia subser. Sphaerocarpae. However, these changes were not accepted by Alex George in his authoritative 1999 contribution to the Flora of Australia

Flora of Australia (series)

The Flora of Australia is a 59 volume series describing the vascular plants, bryophytes and lichens present in Australia and its external territories...

 series.

Distribution and habitat

B. micrantha occurs amongst heath on sand or sand over laterite on the gentle slopes of lateritic hills between Eneabba and Cervantes in Western Australia. It has been declared as "Priority Three - Poorly Known Taxa" under the Wildlife Conservation Act 1950

Wildlife Conservation Act 1950

The Wildlife Conservation Act 1950 is an act of the Western Australian Parliament that provides the statute relating to conservation and legal protection of flora and fauna....

, indicating that it is in need of further survey.