Euphrasia arguta
Encyclopedia
Euphrasa arguta is a plant from the genus Euphrasia
Euphrasia
Euphrasia is a genus of about 450 species of herbaceous flowering plants in the family Orobanchaceae , with a cosmopolitan distribution. They are semi-parasitic on grasses and other plants...

(eyebrights) within the family Orobanchaceae
Orobanchaceae
Orobanchaceae, the broomrape family, is a family of flowering plants of the order Lamiales, with about 90 genera and more than 2000 species. Many of these genera were formerly included in the family Scrophulariaceae sensu lato...

.

The species was last recorded in June 1904 near Tamworth, New South Wales, Australia, and was presumed extinct until rediscovered in 2008 by Forests worker Graham Marshall in NSW's Nundle
Nundle, New South Wales
Nundle is a village in the New England region of New South Wales, Australia. It was formerly the centre of Nundle Shire Local Government Area, but most of this area, including the village of Nundle, was absorbed into Tamworth Regional Council in 2004. The village is 400 km north of Sydney and...

 State Forest.

Some scientists consider that it is a variety of the threatened Rough Eyebright (Euphrasia scabra). Previously the whole genus Euphrasia was regarded as part of the family Scrophulariaceae
Scrophulariaceae
Scrophulariaceae, the figwort family, are a family of flowering plants. The plants are annual or perennial herbs with flowers with bilateral or rarely radial symmetry. Members of the Scrophulariaceae have a cosmopolitan distribution, with the majority found in temperate areas, including...

. It was first described by Robert Brown
Robert Brown (botanist)
Robert Brown was a Scottish botanist and palaeobotanist who made important contributions to botany largely through his pioneering use of the microscope...

 in his reference work Prodromus Florae Novae Hollandiae et Insulae Van Diemen
Prodromus Florae Novae Hollandiae et Insulae Van Diemen
Prodromus Florae Novae Hollandiae et Insulae Van Diemen is an 1810 flora of Australia by botanist Robert Brown. Often referred to as Prodromus Flora Novae Hollandiae, or by its standard botanical abbreviation Prodr. Fl. Nov. Holland., it was the first attempt at a survey of the Australian flora...

 in 1810.

Description

The erect stem
Plant stem
A stem is one of two main structural axes of a vascular plant. The stem is normally divided into nodes and internodes, the nodes hold buds which grow into one or more leaves, inflorescence , conifer cones, roots, other stems etc. The internodes distance one node from another...

 of this annual herb
Herb
Except in botanical usage, an herb is "any plant with leaves, seeds, or flowers used for flavoring, food, medicine, or perfume" or "a part of such a plant as used in cooking"...

 reaches a height from 20 to 35 centimetres and is covered with dense hairs. The deeply lobed leaves are opposite. The upper stem leaves with a length of about six to fourteen millimetres and a width from 3.5 to 13 millimetres are ovate-ellyptic. The 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 consists of 50 to 90 flowers. The length of the usually scabrous calyx
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...

 reaches from 5.5 to 7 millimetres. The corolla measures from ten to fourteen millimetres coloured from white to lilac with yellow markings. The tube is 6.7 to 8.5 millimetres long and the anthers
Stamen
The stamen is the pollen producing reproductive organ of a flower...

 0.9 to 1.7 millimetres. The capsule
Capsule (fruit)
In botany a capsule is a type of simple, dry fruit produced by many species of flowering plants. A capsule is a structure composed of two or more carpels that in most cases is dehiscent, i.e. at maturity, it splits apart to release the seeds within. A few capsules are indehiscent, for example...

 has a length of 4 to 7.5 millimetres and is bristly at the upper half. Like the other eyebright species Euphrasia arguta is a partial parasite and is connected through a haustorium
Haustorium
In botany, a haustorium is the appendage or portion of a parasitic fungus or of the root of a parasitic plant that penetrates the host's tissue and draws nutrients from it. Haustoria do not penetrate the host's cell membranes.Fungi in all major divisions form haustoria...

 to the root
Root
In vascular plants, the root is the organ of a plant that typically lies below the surface of the soil. This is not always the case, however, since a root can also be aerial or aerating . Furthermore, a stem normally occurring below ground is not exceptional either...

lets of other plants.

The flowering period is from October to January.

Occurrence

Its previous habitat consists of grassy areas near rivers in elevations until 700 m asl with an annual rainfall of 600 mm. It was native in the ecoregion
Ecoregion
An ecoregion , sometimes called a bioregion, is an ecologically and geographically defined area that is smaller than an ecozone and larger than an ecosystem. Ecoregions cover relatively large areas of land or water, and contain characteristic, geographically distinct assemblages of natural...

s North Coast
North Coast, New South Wales
Northern Rivers is a region of the Australian state of New South Wales, located between 590 and 820 kilometres north of the state capital, Sydney...

 (NC), Northern Tablelands (NT), Central Tablelands (CT), North West Slopes (NWS) and Central West Slopes (CWS) in the Australian state of New South Wales
New South Wales
New South Wales is a state of :Australia, located in the east of the country. It is bordered by Queensland, Victoria and South Australia to the north, south and west respectively. To the east, the state is bordered by the Tasman Sea, which forms part of the Pacific Ocean. New South Wales...

, in particular in the areas from Bathurst
Bathurst, New South Wales
-CBD and suburbs:Bathurst's CBD is located on William, George, Howick, Russell, and Durham Streets. The CBD is approximately 25 hectares and surrounds two city blocks. Within this block layout is banking, government services, shopping centres, retail shops, a park* and monuments...

 to Walcha
Walcha, New South Wales
Walcha is a parish and town at the south-eastern edge of the Northern Tablelands, New South Wales, Australia.The town serves as the seat of Walcha Shire. Walcha is located 425 kilometres by road from Sydney at the intersection of the Oxley Highway and Thunderbolts Way...

.

Status

In 1982 Australian botanist William R. Barker stated in his study "Taxonomic studies in Euphrasia L. (Scrophulariaceae). A revised infrageneric classification, and a revision of the genus in Australia" in the Journal of the Adelaide Botanic Gardens that Euphrasia arguta was not collected for at least 75 years. In 1997 the World Conservation Monitoring Centre
World Conservation Monitoring Centre
The United Nations Environment Programme's World Conservation Monitoring Centre is an executive agency of the United Nations Environment Programme, based in Cambridge in the United Kingdom. UNEP-WCMC has been part of UNEP since 2000, and has responsibility for biodiversity assessment and support...

 compiled it into the IUCN Red List of Threatened Plants within the category "globally extinct". After the enacting of the Environment Protection and Biodiversity Conservation Act in 2000 it was listed as officially extinct in July 2000 by the Australian government
Government of Australia
The Commonwealth of Australia is a federal constitutional monarchy under a parliamentary democracy. The Commonwealth of Australia was formed in 1901 as a result of an agreement among six self-governing British colonies, which became the six states...

.

On 6 July 2008 Ian MacDonald, New South Wales Primary Industries Minister, announced that Forestry Workers had rediscovered specimens of Euphrasia arguta in Nundle State Forest, New South Wales.

Further reading

  • Harden, Gwen J. (ed.) 1992. Flora of New South Wales vol 3. UNSW Press. ISBN 0868401722
  • Barker, William R. 1982. Taxonomic studies in Euphrasia L. (Scrophulariaceae). A revised infrageneric classification, and a revision of the genus in Australia in Journal of the Adelaide Botanic Gardens

External links

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