Underground orchid (Rhizanthella gardneri) Interim Recovery Plan 2003-2008

Interim recovery plan no. 127
Andrew Brown, Andrew Batty, Mark Brundrett & Kingsley Dixon
Department of Conservation and Land Management, WA, 2003

4. Term of plan

This Interim Recovery Plan will operate from February 2003 to January 2008 but will remain in force until withdrawn or replaced. It is intended that, if the taxon is still ranked as Critically Endangered after four years, Action 14 above will be implemented.

5. Acknowledgements

The following people have provided assistance and advice in the preparation of this Interim Recovery Plan:

Ryan Butler    Conservation Officer, the Department's Esperance District
Kim Kershaw    Conservation Officer, the Department's Narrogin District
Greg Durell    Operation officer, the Department's Narrogin District
Bret Beecham    Regional Ecologist, the Department's Wheatbelt Region

We would like to thank the staff of the W.A. Herbarium for providing access to Herbarium databases and specimen information, and the Department's Wildlife Branch for their extensive assistance.

6. References

Brown, A., Thomson-Dans, C. and Marchant, N. (Eds). (1998) Western Australia's Threatened Flora. Department of Conservation and Land Management, Western Australia.

Brown, A. (2002) Endangered, Underground Orchid. Landscope - WA's Conservation, Parks and Wildlife Magazene 17(3): 42.

Dixon, K. W., et al. (1990). The Western Australian fully subterranean orchid Rhizanthella gardneri. Orchid Biology, Reviews and Perspectives. V. J. Arditti. Portland, Oregon, Timber Press. 5: 37-62.

Dixon, K. W. and Pate, J. S. (1984). Biology and Distributional Status of Rhizanthella gardneri Rogers. Kings Park Research Notes 9.

George, A. S. (1981). Rhizanthella-The Underground Orchid of Western Australia. Proceedings of the Orchid Symposium, 13th International Botanical Congress 77-78.

George, A. S. (1980). Rhizanthella gardneri R.S. Rogers-The Underground Orchid of Western Australia. American Orchid Society Bulletin 49: 631-646.

Meston, J. (2001). Mapping and monitoring salinity: The Ravensthorpe Landsat TM scene (109-083). CSIRO Mathematical and Information Sciences. CMIS report number: 01/111.

The Department (1992) Policy Statement No. 44 Wildlife Management Programs. Department of Conservation and Land Management, Western Australia.

The Department (1994) Policy Statement No. 50 Setting Priorities for the Conservation of Western Australia's Threatened Flora and Fauna. Department of Conservation and Land Management, Western Australia.

The Department (1995) Policy Statement No. 29 Translocation of Threatened Flora and Fauna. Department of Conservation and Land Management, Western Australia.

The Department (1998) Western Australian Herbarium FloraBase - Information on the Western Australian Flora. Department of Conservation and Land Management, Western Australia. http://www.calm.wa.gov.au/science/

Warcup, J. H. (1985). Rhizanthella gardneri (Orchidaceae), its Rhizoctonia endophyte and close association with Melaleuca uncinata (Myrtaceae) in Western Australia. New Phytologist 99: 273-280.

Warcup, J. H. (1991). The Rhizoctonia endophytes of Rhizanthella (Orchidaceae). Mycological Research 95: 656-659.

World Conservation Union (2000) IUCN red list categories prepared by the IUCN Species Survival Commission, as approved by the 51st meeting of the IUCN Council. Gland, Switzerland.

7. Taxonomic description

Rhizanthella gardneri is a small subterranean epi-parasitic herb. Rhizomes short, thickened, without roots, branching. Inflorescences erect, subsessile, solitary, terminal; those on the smaller lateral rhizomes with well developed bracteate stems. Capitula up to 5 cm in diameter; bracts rather large, ovate or oblong-lanceolate, imbricate, up to 5 cm long, slightly spreading at the apices, in my specimens about 12 in number. Flowers numerous, small, sessile, dark purple, crowded, facing the center, arranged in 4 or 5 whorls. Sepals and petals erect, about 4 mm long, connate in a split tube 3-lobed at the apex. Dorsal sepal cucullate, adnate in its lower half with the petals and back of the column, triangular-ovate, rather wide, concave, abruptly incurved at the apex, ending in a short recurved apiculum; lateral sepals very fleshy, connate in their lower half, widely triangular, their apices short acute enclosing a sinus. Petals oblong-falcate, acute. Membranous, slightly shorter and much narrower than the sepals and hidden by the latter, adnate in the lower half by the posterior margins to the dorsal sepal and column, forming a galea with the former. Labellum reddish, attached to the apex of the column-foot by a delicate movable claw, linguiform, conspicuous, very large in comparison with the size of the flower, the apex subacute, glandular, undivided, very fleshy, erect against the column then recurved; lamina longitudinally concave, the tip slightly protruding from the galea. Column erect, almost equal in length to the sepals, not winged, terete, adnate to the petals and dorsal sepal, produced into a short foot at the base. Anther persistent, terminal, erect, without a point, rather obtuse, compressed laterally at the apex, rather widely attached to the posterior margin of the clinandrium, valvate, 2-celled. Clinandrium slightly concave. Pollinia 4, granular, almost sessile on the minute viscidium of the rostellum. Stigma prominent vertical, ovate, rather large. Rostellum erect, emarginate at the apex, much shorter than the anther. Ovary white, terete, up to 7mm long, the subtending bract lanceolate, equal to or sometimes longer than the ovary.

Addendum

Underground Orchid (Rhizanthella gardneri) Interim Recovery Plan 2003-2008

In adopting this plan under the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act), the Minister for the Environment and Heritage has approved the following modifications.

Critical Habitat
The plan identifies a broad area as critical habitat, including buffer zones of a set distance around known populations. The Threatened Species Scientific Committee does not necessarily believe that such an area qualifies as habitat critical to the survival of the species, as defined in the EPBC Act.

Recovery Criteria
For the purposes of reviewing this recovery plan under the EPBC Act, the Recovery Criteria are amended to read as follows:

Criteria for success: The number of individuals within populations and/or the number of populations have increased by 10% or more over the period of the plan's adoption under the EPBC Act.
Criteria for failure: The number of individuals within populations and/or the number of populations have decreased by 10% or more over the period of the plan's adoption under the EPBC Act.