Indicative distribution
The areas shown in pink and/purple are the sub-regions where the species or community is known or predicted to occur. They may not occur thoughout the sub-region but may be restricted to certain areas.
(
click here to see geographic restrictions).
The information presented in this map is only indicative and may contain errors and omissions.
Scientific name: Pterostylis despectans
Gazetted date:
28 Mar 2008
Profile last updated:
02 Mar 2022
Description
Pterostylis despectans is a terrestrial herb with flowering stems 30-80 mm tall, 6-10 basal leaves in a rosette, and 3 or 4 stem-sheathing bract-like leaves above, the rosette leaves are 10-20 mm long and 6-9 mm wide. There are 1-6 flowers, usually with up to 4 open at a time, on slender pedicels up to 15 mm long spreading widely from the stalk. Flowering occurs in October and November. Pterostylis despectans is not easily confused with other orchid species, being characterised by the flower colours, a short flower stem, long spreading pedicels, sepal points often resting on the soil, and a labellum with two prominent basal bristles.
Distribution
In New South Wales the species is known only from a single population discovered in 2005 near Moama in the Riverina district. The site is within the Murray Local Government Area. Several surveys of Riverina grassland and regional Travelling Stock Reserves did not record P. despectans and it seems likely that the species is extremely rare in New South Wales. The species also occurs as very small fragmented populations in central Victoria and in South Australia. The total estimated number of individuals in the Victorian and South Australian populations is less than 1500. The Moama population has been assessed as comprising between 20 and 60 individual plants. All plants known to date occur within an area of about one hectare, within an apparently suitable habitat patch-size of about 20 ha. Pterostylis despectans is not known to occur in any NSW conservation reserves.
Habitat and ecology
- The plant remains dormant underground as a tuber in late summer into early winter. In winter it develops a rosette of six to ten leaves. The flower stem is produced between late October and December and the leaves shrivel up by the time the flowers mature. Like most Australian terrestrial orchids the species is believed to be partly or fully dependent on a mycorrhizal symbiont.
- The New South Wales population occurs in natural forb-rich grassland on flat alluvial plains and not derived from Acacia pendula woodland. The only tree species recorded as present at the site is Allocasuarina luehmannii.
- The soil is a reddish, probably calcareous, clay loam.
- The community is described as occurring on plains of Quaternary alluvial sediments with an annual rainfall of 405-465 mm.
Regional distribution and habitat
Click on a region below to view detailed distribution, habitat and vegetation information.
Threats
- The species may be further threatened by future changes to stock access and grazing, especially if a stock-watering point were to be added to the site.
- Competition from annual exotic grasses and Romulea spp. which are encroaching from a road drain and an easement on the site.
- The species is susceptible to extinction via stochastic processes due to its small known population size and restricted distribution.
- Disturbance due to activities including the building and maintanence of roads and tracks
- Current or potential future land management practices do not support conservation
Recovery strategies
A targeted strategy for managing this species has been developed under the Saving Our Species program; click
here for details. For more information on the Saving Our Species program click
here
Activities to assist this species
- Grazing, fire and other management regimes for conservation of P. despectans have not been determined, however heavy grazing should not occur.
- The removal of exotic or over dominant native species may help the survival of the species.
- Protect the species from large disturbance impacts.
Information sources
- Bickerton, D. and Robertson, M. (2000) Lowly Greenhood (Pterostylis despectans) 'Mt Bryan' Recovery Plan. Threatened Species Network, Threatened Plant Action Group.
- Coates, F., Jeanes, J. and Pritchard, A. (2002) Recovery Plan for Twenty- five Threatened Orchids of Victoria, South Australia and New South Wales 2003 - 2007. (Department of Sustainability and Environment, Melbourne)
- Department of Sustainability and Environment (2001) Action Statement No. 123 - Lowly Greenhood Pterostylis despectans. DSE, Melbourne.
- Department of the Environment, Water, Heritage and the Arts (2010) Pterostylis despectans in Species Profile and Threats Database, Department of the Environment, Water, Heritage and the Arts, Canberra.
- NSW Scientific Committee (2008) Pterostylis despectans (terrestrial herb) - critically endangered species listing. Final determination DEC (NSW), Sydney.
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