Prasophyllum fuscum
{{Short description|Species of orchid}}
{{Italic title}}
{{Speciesbox
| name = Slaty leek orchid
| image = Prasophyllum fuscum.jpg
| image_caption =
| status_system = EPBC
| status = VU
| taxon = Prasophyllum fuscum
| authority= R.Br.
| display_parents = 3
| synonyms = Prasophyllum uroglossum Rupp
| synonyms_ref ={{WCSP | 164832 | Prasophyllum uroglosum }}
}}
Prasophyllum fuscum, commonly known as the slaty leek orchid or tawny leek orchid, is a species of orchid endemic to a small region of New South Wales. It has a single tubular green leaf and up to thirty greenish brown to reddish brown flowers. There is debate about the taxonomy of the species with some authorities considering Prasophyllum uroglossum as a separate species. Only about twenty five plants are known to survive in south-western Sydney.
Description
Prasophyllum fuscum is a terrestrial, perennial, deciduous, herb with an underground tuber and a single tube-shaped leaf {{convert|150-400|mm|in|sigfig=1|abbr=on}} long and {{convert|4-6|mm|in|sigfig=2|abbr=on}} wide at the base. Between ten and thirty scented flowers are arranged along {{convert|70-120|mm|in|sigfig=1|abbr=on}} of a flowering stem {{convert|300-450|mm|in|sigfig=1|abbr=on}} tall. The flowers are greenish brown to reddish brown, {{convert|9-13|mm|in|sigfig=1|abbr=on}} long, {{convert|5-7|mm|in|sigfig=1|abbr=on}} wide and as with others in the genus, are inverted so that the labellum is above the column rather than below it. The dorsal sepal is egg-shaped to lance-shaped, about {{convert|9|mm|in|sigfig=1|abbr=on}} long, {{convert|2|mm|in|sigfig=1|abbr=on}} wide and pointed. The lateral sepals are linear to lance-shaped, {{convert|8-10|mm|in|sigfig=1|abbr=on}} long, {{convert|2|mm|in|sigfig=2|abbr=on}} wide and parallel to and free from each other. The petals are linear to oblong, pointed, about {{convert|7|mm|in|sigfig=1|abbr=on}} long, {{convert|1.5|mm|in|sigfig=1|abbr=on}} wide and spread widely. The labellum is linear to egg-shaped, {{convert|8-9|mm|in|sigfig=1|abbr=on}} long, about {{convert|5|mm|in|sigfig=1|abbr=on}} wide and turns upwards through about 90° near its middle. The edges of the labellum are slightly crinkled and there is a shiny, raised callus in its centre. Flowering occurs between September and December.{{cite web|title=Prasophyllum fuscum R.Br. sens. str. - critically endangered species listing|url=http://www.environment.nsw.gov.au/determinations/prasophyllumfuscumFD.htm|publisher=Government of New South Wales Office of Environment and Heritage|accessdate=15 November 2017}}
Taxonomy and naming
Prasophyllum fuscum was first formally described in 1810 by Robert Brown from a specimen collected in "moist meadows towards George's River". The description was published in Prodromus Florae Novae Hollandiae et Insulae Van Diemen.{{cite web|title=Prasophyllum fuscum|url= https://id.biodiversity.org.au/instance/apni/533750|publisher=APNI|accessdate=15 November 2017}}{{cite book|last1=Brown|first1=Robert|title=Prodromus Florae Novae Hollandiae et Insulae Van Diemen|date=1810|location=London|page=318|url=https://www.biodiversitylibrary.org/item/21871#page/186/mode/1up|accessdate=15 November 2017}} The specific epithet (fuscum) is a Latin word meaning "brown".{{cite book|last1=Brown|first1=Roland Wilbur|title=The Composition of Scientific Words|date=1956|publisher=Smithsonian Institution Press|location=Washington, D.C.|page = 168}} The name has been applied to other species widely distributed throughout south-eastern Australia, including P. pallens, but the species is presently understood to be restricted to an area south-west of Sydney.
Distribution and habitat
Conservation
Prasophyllum fuscum is listed as "Vulnerable" under the Commonwealth Government Environment Protection and Biodiversity Conservation Act 1999 (EPBC) Act and as "Critically Endangered" under the New South Wales Threatened Species Conservation Act 1995. The total population of the species was estimated in 2007 to be twenty five individuals in an area of {{convert|4|km2|mi2|sigfig=1|abbr=on}}. The main threats to the population are habitat loss, changes to water quality and weed invasion.{{cite web|title=Approved Conservation Advice for Prasophyllum fuscum (Tawny Leek-orchid)|url=http://www.environment.gov.au/biodiversity/threatened/species/pubs/19455-conservation-advice.pdf|publisher=Australian Government Department of the Environment|accessdate=15 November 2017}}
References
{{Reflist|30em}}
External links
- {{Commons-inline|Prasophyllum fuscum|Prasophyllum fuscum}}
- {{Wikispecies-inline|Prasophyllum fuscum|Prasophyllum fuscum}}
{{Taxonbar|from=Q15488111}}
Category:Flora of New South Wales