Archeria racemosa
Encyclopedia
Archeria racemosa is a species
of shrub in the heath family (Ericaceae
).
(where it is endemic), being found scattered throughout Little Barrier Island, Great Barrier Island
, the Coromandel Peninsula
, and from the Bay of Plenty
across to East Cape
.
s and forest margins, at lowland
to montane
altitude
s. Flowering takes place from December to January, and fruiting from February to April.
, to 5 m tall but often much shorter. It has spreading branches, with leaves that tend to cluster towards the ends of the branches. The bark is dark brown to black in colour. Leaves Broad leathery leaves that are obovate to elliptic-oblong in shape, often with sharp tips (acute to apiculate). The base of the leaf is rigid and nearly sessile
, attached to the stem with a short and flat petiole
. Dimensions are roughly 25-40 mm long and 8-12 mm wide. Leaf margins are entire, and flat to slightly recurved. Prominent venation can be seen on the abaxial sides of some leaves (3-5 veined), but this is indistinct on others. When crushed the leaves have an almost pungent smell at times. Inflorescence A solitary terminal raceme
, with 10-20(30) flowers, ranging from 25-45 mm in length. The axis is pubescent, with short curved pedicels
. Bract
s are light red to pinkish, ciliolate, and caducous. Flowers & Fruits The flowers are perfect, small, urn shaped, and white to bright pink in colour (often lighter at the base and darkening towards the corolla lobes). The sepal
s are almost free, roughly 2-3 mm long, oblong-lanceolate, and blunt with ciliolate margins. The corolla is around 6 mm long, with the tube making up 4 mm and the lobes the other 2 mm. Ovary is deeply 5-lobed, with a stout persistent style
. Capsules are 2-3 mm in diametre, subglobose, with 3-5 locules. A second form of flowers has rarely been observed during years of heavy flowering. This form is a shorter more erect and compact raceme of light yellow male flowers. The corolla tubes are shorter and the bracts more spread out.
A. racemosa appears to most closely resemble A. traversii
, the only other New Zealand species in the genus.
was named by Joseph Dalton Hooker
in 1844 after the nineteenth century Tasmanian
botanist W. Archer. The specific epithet "racemosa" refers to the racemes of flowers, and was given to the plant in 1864, again by Hooker.
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 in the heath family (Ericaceae
Ericaceae
The Ericaceae, commonly known as the heath or heather family, is a group of mostly calcifuge flowering plants. The family is large, with roughly 4000 species spread across 126 genera, making it the 14th most speciose family of flowering plants...
).
Distribution
A. racemosa currently occupies a rather restricted range in northern New ZealandNew Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...
(where it is endemic), being found scattered throughout Little Barrier Island, Great Barrier Island
Great Barrier Island
Great Barrier Island is a large island of New Zealand, situated to the north-east of central Auckland in the outer Hauraki Gulf. With an area of it is the fourth-largest island of New Zealand's main chain of islands, with its highest point, Mount Hobson, rising...
, the Coromandel Peninsula
Coromandel Peninsula
The Coromandel Peninsula lies in the North Island of New Zealand. It is part of the Waikato Region and Thames-Coromandel District and extends 85 kilometres north from the western end of the Bay of Plenty, forming a natural barrier to protect the Hauraki Gulf and the Firth of Thames in the west...
, and from the Bay of Plenty
Bay of Plenty
The Bay of Plenty , often abbreviated to BOP, is a region in the North Island of New Zealand situated around the body of water of the same name...
across to East Cape
East Cape
East Cape is the easternmost point of the main islands of New Zealand. It is located to the north of Gisborne in the northeast of the North Island....
.
Ecology
It is largely found in shrublandShrubland
Shrubland, scrubland, scrub or brush is a plant community characterized by vegetation dominated by shrubs, often also including grasses, herbs, and geophytes. Shrubland may either occur naturally or be the result of human activity...
s and forest margins, at lowland
Lowland
In physical geography, a lowland is any broad expanse of land with a general low level. The term is thus applied to the landward portion of the upward slope from oceanic depths to continental highlands, to a region of depression in the interior of a mountainous region, to a plain of denudation, or...
to montane
Montane
In biogeography, montane is the highland area located below the subalpine zone. Montane regions generally have cooler temperatures and often have higher rainfall than the adjacent lowland regions, and are frequently home to distinct communities of plants and animals.The term "montane" means "of the...
altitude
Altitude
Altitude or height is defined based on the context in which it is used . As a general definition, altitude is a distance measurement, usually in the vertical or "up" direction, between a reference datum and a point or object. The reference datum also often varies according to the context...
s. Flowering takes place from December to January, and fruiting from February to April.
Morphology
Habit An erect shrubShrub
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...
, to 5 m tall but often much shorter. It has spreading branches, with leaves that tend to cluster towards the ends of the branches. The bark is dark brown to black in colour. Leaves Broad leathery leaves that are obovate to elliptic-oblong in shape, often with sharp tips (acute to apiculate). The base of the leaf is rigid and nearly sessile
Sessility (botany)
In botany, sessility is a characteristic of plants whose flowers or leaves are borne directly from the stem or peduncle, and thus lack a petiole or pedicel...
, attached to the stem with a short and flat petiole
Petiole (botany)
In botany, the petiole is the stalk attaching the leaf blade to the stem. The petiole usually has the same internal structure as the stem. Outgrowths appearing on each side of the petiole are called stipules. Leaves lacking a petiole are called sessile, or clasping when they partly surround the...
. Dimensions are roughly 25-40 mm long and 8-12 mm wide. Leaf margins are entire, and flat to slightly recurved. Prominent venation can be seen on the abaxial sides of some leaves (3-5 veined), but this is indistinct on others. When crushed the leaves have an almost pungent smell at times. Inflorescence A solitary terminal raceme
Raceme
A raceme is a type of inflorescence that is unbranched and indeterminate and bears pedicellate flowers — flowers having short floral stalks called pedicels — along the axis. In botany, axis means a shoot, in this case one bearing the flowers. In a raceme, the oldest flowers are borne...
, with 10-20(30) flowers, ranging from 25-45 mm in length. The axis is pubescent, with short curved pedicels
Pedicel (botany)
A pedicel is a stem that attaches single flowers to the main stem of the inflorescence. It is the branches or stalks that hold each flower in an inflorescence that contains more than one flower....
. Bract
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 often different from foliage leaves. They may be smaller, larger, or of a different color, shape, or texture...
s are light red to pinkish, ciliolate, and caducous. Flowers & Fruits The flowers are perfect, small, urn shaped, and white to bright pink in colour (often lighter at the base and darkening towards the corolla lobes). The sepal
Sepal
A sepal is a part of the flower of angiosperms . Collectively the sepals form the calyx, which is the outermost whorl of parts that form a flower. Usually green, sepals have the typical function of protecting the petals when the flower is in bud...
s are almost free, roughly 2-3 mm long, oblong-lanceolate, and blunt with ciliolate margins. The corolla is around 6 mm long, with the tube making up 4 mm and the lobes the other 2 mm. Ovary is deeply 5-lobed, with a stout persistent style
Style
Style may refer to:* Style , an aspect of literary composition* Style , in art and painting, either the aesthetic values followed in choosing what to paint or to the physical techniques employed* Architectural style...
. Capsules are 2-3 mm in diametre, subglobose, with 3-5 locules. A second form of flowers has rarely been observed during years of heavy flowering. This form is a shorter more erect and compact raceme of light yellow male flowers. The corolla tubes are shorter and the bracts more spread out.
Evolutionary History
The phylogeny of the genus remains unknown, but morphologicallyMorphology (biology)
In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....
A. racemosa appears to most closely resemble A. traversii
Archeria traversii
Archeria traversii is a species of shrub in the heath family .-Distribution:A. traversii is scattered locally across southern New Zealand , where it is endemic...
, the only other New Zealand species in the genus.
Conservation Status
A. racemosa is currently regarded as naturally uncommon, and non threatened.Etymology
ArcheriaArcheria (plant genus)
Archeria is a small genus of shrubs in the heath family . As currently circumscribed the group includes six species, all native to southern Australasia...
was named by Joseph Dalton 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...
in 1844 after the nineteenth century Tasmanian
Tasmania
Tasmania is an Australian island and state. It is south of the continent, separated by Bass Strait. The state includes the island of Tasmania—the 26th largest island in the world—and the surrounding islands. The state has a population of 507,626 , of whom almost half reside in the greater Hobart...
botanist W. Archer. The specific epithet "racemosa" refers to the racemes of flowers, and was given to the plant in 1864, again by Hooker.