Leucospermum hypophyllocarpodendron

Leucospermum hypophyllocarpodendron is a creeping, mat-forming shrub with heads of yellow flowers and leathery, upright narrow leaves with some red-tipped teeth at their tips, from the family Proteaceae. It has long thin branches that originate from an underground rootstock and grows on poor, sandy soils in southwestern South Africa. The rose-scented flower heads can be found for August to January and are visited by different monkey beetles, bees and flies. It has two subspecies, one with greyish leaves U-shaped in cross section called grey snakestem pincushion in English and gruisslangbossie in Afrikaans, the other with green leaves that are flat in cross-section called green snakestem pincushion and groenslangbossie.

Description

Leucospermum hypophyllocarpodendron is a prostrate shrub of no more than high, with branches that spread out over the ground and form mats of 0.5–1.5

Subspecies

The snakestem pincushion has two subspecies.

Image	Subspecies	Common name	Description
	L. hypophyllocarpodendron subsp. hypophyllocarpodendron	green snakestem pincushion	The typical subspecies, characterised by flat narrowly lance-shaped leaves with a green appearance that are more or less hairless from the beginning.
	L. hypophyllocarpodendron subsp. canaliculatum	grey snakestem pincushion	linear to narrowly lance-shaped leaves that are U-shaped in cross-section that are initially grey because of a dense covering of fine, soft, crisped hair, some of which may wear off when aging, particularly where exposed.

Differences with other species

Although L. hypophyllocarpodendron is not closely related, it can easily be mistaken for L. prostratum that is also a trailing shrub with upright leaves and small yellow flower heads, but that species has entire, flat, lance-shaped leaves, and all four perianth lobes are free and roll back on themselves. L. hypophyllocarpodendron differs from its relatives of the section Leucospermum because it is the only one with a prostrate habit with trailing branches, with up-right leaves, sometimes U-shaped in cross-section, and broad involucral bracts.

Taxonomy

The snakestem pincushion was described several times before the start of binomial nomenclature. In 1696, Leonard Plukenet, an early English botanist and gardener to Queen Mary, described it as: Leucadendros Africana sive Scolymocephalus, angustiori folio, apicibus tridentatis. Other early authors are John Ray, Herman Boerhaave, George Clifford III, Adriaan van Royen and Johann Anton Weinmann. The species was first validly described by Carl Linnaeus in his 1753 work Species Plantarum, as Leucadendron hypophyllocarpodendron, one of the longest names in that work. Linnaeus transferred the species to Protea in his Mantissa Plantarum. In 1781, Carl Peter Thunberg simplified Linnaeus' name and combined it to Protea hypophylla, which is a so-called superfluous name. Joseph Knight published a book in 1809 titled On the cultivation of the plants belonging to the natural order of Proteeae, that contained an extensive revision of the Proteaceae attributed to Richard Anthony Salisbury. Salisbury assigned the snakestem pincushion species Leucadendrum, accepting the simplified species name, creating Leucadendrum hypophyllum. When he erected the segregate genus Leucospermum in 1810, Robert Brown called the species Leucospermum hypophyllum; this is the type species of the genus Leucospermum. Under the current rules of plant nomenclature, the oldest specific epithet must be used; George Claridge Druce rectified this situation when he published the new combination Leucospermum hypophyllocarpodendron alongside dozens of similar cases in 1913.
In 1843, Heinrich Wilhelm Buek created the name Leucospermum canaliculatum without a proper description, but that was corrected by Carl Meissner in 1856, who regarded it as a variety of L. hypophyllum. Meisner also described Leucospermum hypophyllum var. stenophyllum in the same book by De Candolle in 1856. Johann Friedrich Klotzsch, a German pharmacist and botanist, in 1845 named a new variety Leucospermum hypophyllum var. angustifolium, also without a proper description. John Patrick Rourke considered in 1970 all of these grey-leaved forms with U-shaped cross-sections synonymous and created the new combination and subspecies L. hypophyllocarpodendron subsp. canaliculatum.
L. hypophyllocarpodendron is both the type species of the genus Leucospermum and the section Leucospermum. The species name hypophyllocarpodendron means "under-leaf fruit tree".

Distribution, habitat and ecology

Leucospermum hypophyllocarpodendron subsp. hypophyllocarpodendron can be found in three isolated areas, that were probably at one time connected when the sea-level was lower than today. The first area is along the coast between Brandfontein and Franskraalstrand. Another area where the subspecies grows is near Faure, Stellenbosch and around the Berg River Dam. Lastly, it occurs on the southern half of the Cape Peninsula. It also used to occur on the flat lands between Retreat and Cape Town, but is now extinct because of the city's expansion. The plants live in fynbos and strandveld on sandy flats below 150 m elevation, but sometimes grow on weathered Table Mountain Sandstone up to 300 m. Adult plants almost always survive the wildfires that occur every decade or two because they grow new branches from the woody underground rootstock.
Leucospermum hypophyllocarpodendron subsp. canaliculatum has its natural distribution along the west coast of the Western Cape, ranging from Milnerton in the south, to Darling in the west and Piketberg in the north, except for an isolated location near the Brandvlei Dam. It grows always on white sands in areas with an average annual rainfall of, most of which falls during the winter. This subspecies is also very resistant against fire.