Archeria (plant genus)
Encyclopedia
Archeria is a small 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...

 of shrubs 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...

). As currently circumscribed the group includes six species, all native to southern Australasia
Australasia
Australasia is a region of Oceania comprising Australia, New Zealand, the island of New Guinea, and neighbouring islands in the Pacific Ocean. The term was coined by Charles de Brosses in Histoire des navigations aux terres australes...

. Four of these are endemic to Tasmania
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...

, and the other two endemic to New Zealand
New 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...

.

It does not contain any economically important taxa, but due to their attractive small tubular flowers, reticulate leaf venation, and limited distribution, the shrubs have a long history of being admired by Australasian naturalist
Naturalist
Naturalist may refer to:* Practitioner of natural history* Conservationist* Advocate of naturalism * Naturalist , autobiography-See also:* The American Naturalist, periodical* Naturalism...

s.

List of Species

  1. Archeria comberi
    Archeria comberi
    Archeria comberi is a species of shrub in the heath family . It is found only in Tasmania.-External Links:* at the * at the...

     Melville (Tasmania)
  2. Archeria eriocarpa
    Archeria eriocarpa
    Archeria eriocarpa is a species of shrub in the heath family . It is endemic to Tasmania, Australia.-External Links:* at * at the * at the...

     Hook. f. (Tasmania)
  3. Archeria hirtella
    Archeria hirtella
    Archeria hirtella is a species of shrub in the heath family . It is native to Tasmania, Australia.-External Links:* at * at the * at the...

     (Hook. f.) Hook. f. (Tasmania)
  4. Archeria racemosa
    Archeria racemosa
    Archeria racemosa is a species of shrub in the heath family .-Distribution:A. racemosa currently occupies a rather restricted range in northern New Zealand , being found scattered throughout Little Barrier Island, Great Barrier Island, the Coromandel Peninsula, and from the Bay of Plenty across to...

     Hook. f. (New Zealand)
  5. Archeria serpyllifolia
    Archeria serpyllifolia
    Archeria serpyllifolia is a species of shrub in the heath family . It is endemic to Tasmania, Australia.-External Links:* at * at the * at the * at the...

     Hook. f. (Tasmania)
  6. Archeria 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...

     (Hook. f.) Mueller (New Zealand)

Distribution

Archeria can be found scattered throughout south, west, north and central Tasmania, but is largely absent from the east. In New Zealand the distribution is highly disjunct
Disjunct distribution
In biology, a taxon with a disjunct distribution is one that has two or more groups that are related but widely separated from each other geographically...

, with A. racemosa being found only in the northern North Island
North Island
The North Island is one of the two main islands of New Zealand, separated from the much less populous South Island by Cook Strait. The island is in area, making it the world's 14th-largest island...

, and A. traversii being scattered locally throughout the South Island
South Island
The South Island is the larger of the two major islands of New Zealand, the other being the more populous North Island. It is bordered to the north by Cook Strait, to the west by the Tasman Sea, to the south and east by the Pacific Ocean...

 and Stewart Island.

Ecology

Like most ericads
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...

, Archeria species are largely found on acidic soils. They grow 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...

 altitudes, although A. comberi
Archeria comberi
Archeria comberi is a species of shrub in the heath family . It is found only in Tasmania.-External Links:* at the * at the...

 and A. hirtella
Archeria hirtella
Archeria hirtella is a species of shrub in the heath family . It is native to Tasmania, Australia.-External Links:* at * at the * at the...

 reach the sub-alpine in parts of their range. Five of the six species are found rather locally throughout shrubland
Shrubland
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
Forest
A forest, also referred to as a wood or the woods, is an area with a high density of trees. As with cities, depending where you are in the world, what is considered a forest may vary significantly in size and have various classification according to how and what of the forest is composed...

s, while A.comberi is found in heath
Heath
-Habitats:* Heath or heathland, low-growing woody vegetation, mostly consisting of heathers and related species* Heaths in the British National Vegetation Classification system...

s, sedgelands
Cyperaceae
Cyperaceae are a family of monocotyledonous graminoid flowering plants known as sedges, which superficially resemble grasses or rushes. The family is large, with some 5,500 species described in about 109 genera. These species are widely distributed, with the centers of diversity for the group...

, and wetland
Wetland
A wetland is an area of land whose soil is saturated with water either permanently or seasonally. Wetlands are categorised by their characteristic vegetation, which is adapted to these unique soil conditions....

s.

Morphology

Habit The six species of Archeria are all self-supporting shrubs with dark coloured bark. Leaves They have simple, alternately arranged glabrous leaves, with margins that are entire or serrulate. The leaves are unique within the Styphelioideae, being the only genus in the group to have reticulate venation. Inflorescence The flowers are pedicellate, and either in short 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...

s or solitary and axillary towards the ends of the branches. Flowers and Fruits Flowers are 5-merous, with 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 and bracteoles that are often small and caducous. The ovary
Ovary (plants)
In the flowering plants, an ovary is a part of the female reproductive organ of the flower or gynoecium. Specifically, it is the part of the pistil which holds the ovule and is located above or below or at the point of connection with the base of the petals and sepals...

 is deeply 5-lobed, with the style
Gynoecium
Gynoecium is most commonly used as a collective term for all carpels in a flower. A carpel is the ovule and seed producing reproductive organ in flowering plants. Carpels are derived from ovule-bearing leaves which evolved to form a closed structure containing the ovules...

 deeply inserted, nearly to the base. Capsules are loculicidally dehiscent
Dehiscence (botany)
Dehiscence is the opening, at maturity, in a pre-defined way, of a plant structure, such as a fruit, anther, or sporangium, to release its contents. Sometimes this involves the complete detachment of a part. Structures that open in this way are said to be dehiscent...

, with many 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...

s, on basal or sub-basal placentae
Placentation
In biology, placentation refers to the formation, type and structure, or arrangement of placentas. The function of placentation is to transfer nutrients from maternal tissue to a growing embryo...

.

Evolutionary History

Based on morphology
Morphology (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....

, and chloroplastic
Chloroplast
Chloroplasts are organelles found in plant cells and other eukaryotic organisms that conduct photosynthesis. Chloroplasts capture light energy to conserve free energy in the form of ATP and reduce NADP to NADPH through a complex set of processes called photosynthesis.Chloroplasts are green...

 matK and rbcL DNA sequence
DNA sequence
The sequence or primary structure of a nucleic acid is the composition of atoms that make up the nucleic acid and the chemical bonds that bond those atoms. Because nucleic acids, such as DNA and RNA, are unbranched polymers, this specification is equivalent to specifying the sequence of...

 data, Archeria is found to be nested within the Styphelioideae subfamily of the 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...

. The genus is sister to the rest of the subfamily, except for the Prionoteae tribe, which is sister to the rest of the subfamily and Archeria. It is regarded as distinct enough, both in terms of morphological and molecular data, to warrant monotypic status within its own tribe, the Archerieae.

Etymology

The genus 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 botanist W. Archer. Interestingly, the name is actually a senior homonym, as the name Archeria was later applied to a group of Early Permian dinosaurs in 1918 (see Archeria (animal genus)).

External Links

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