Assessment Report - Polystachya ngomensis

	IUCN Species Information Service (SIS) Toolkit
	Assessment Report

Taxonomy
Kingdom	Phylum	Class	Order	Family
PLANTAE	TRACHEOPHYTA	LILIOPSIDA	ASPARAGALES	ORCHIDACEAE

Scientific Name:	Polystachya ngomensis
Species Authority:	G.McDonald & McMurtry
Common Name/s: -
Synonym/s:	-
Taxonomic Notes:	-

Assessment Information
Red List Category & Criteria:	Vulnerable B1ab(iii)+2ab(iii)
Year Assessed:	2023
Assessor/s:	Braun, K. & Loffler, L.
Reviewer/s:	Raimondo, D.
Contributor/s:
Facilitator/s:
Institutions/s:
Justification: This species has a restricted distribution, with an extent of occurrence (EOO) of 6,333,877 km², and an area of occupancy (AOO) of 32 km² , it is known from seven locations and one or two more may exist in under surveyed parts of its range. There is ongoing slow habitat degradation impacting the majority of the population. Based on this, it has been assessed as Vulnerable, under Criterion B.
History:	-

Geographic Range
Range Description:	This species is known from near the Eswatini border in Mpumalanga, South Africa, extending south through the Eswatini highveld, to the Ngome area in KwaZulu Natal.
Countries:	Native: Eswatini; KwaZulu-Natal; Mpumalanga;

Population
Population:	No detailed population surveys have been conducted for this species, however at one location in Mpumalanga, it was recorded as being prolific, with numerous seedlings present. A population decline is suspected due to a gradual decline in small forest patches within grassland areas, although the majority of the Eswatini observations are of this species as an epiphyte on Xerophyta retinervis, which has a more stable population.
Population Trend:	Decreasing

Population

Population:

No detailed population surveys have been conducted for this species, however at one location in Mpumalanga, it was recorded as being prolific, with numerous seedlings present. A population decline is suspected due to a gradual decline in small forest patches within grassland areas, although the majority of the Eswatini observations are of this species as an epiphyte on Xerophyta retinervis, which has a more stable population.

Population Trend:

Decreasing

Habitat and Ecology
Habitat and Ecology:	This species is epiphytic on a variety of tree species, and in Eswatini, it has primarily been found growing on mature tall Xerophyta retinervis, although it has also been seen on Podocarpus latifolius. The vegetation types where this species has been found are grassland areas, including Barberton Montane Grassland (Gm17), KaNgwane Montane Grassland (Gm16), and Northern Zululand Mistbelt Grassland (Gs1) (Mucina et. al. 2018).
List of Habitats:	4 Grassland 4.7 Grassland - Subtropical/Tropical High Altitude

Habitat and Ecology

Habitat and Ecology:

This species is epiphytic on a variety of tree species, and in Eswatini, it has primarily been found growing on mature tall Xerophyta retinervis, although it has also been seen on Podocarpus latifolius. The vegetation types where this species has been found are grassland areas, including Barberton Montane Grassland (Gm17), KaNgwane Montane Grassland (Gm16), and Northern Zululand Mistbelt Grassland (Gs1) (Mucina et. al. 2018).

List of Habitats:

4 Grassland
4.7 Grassland - Subtropical/Tropical High Altitude

Threats
Major Threat(s):	As this species is epiphytic it is dependent on the presence of trees and or Xerophyta retinervis within the grassland areas, and there is ongoing habitat degradation of forested areas within the highveld grassland areas. The small forest patches within grassland are being degraded from logging and the spread of invasive alien Acacia species. Furthermore, repeated hot fires negatively impact the Xerophyta population causing slow ongoing decline to this species.
List of Threats:	5 Biological resource use 5.3 Logging & wood harvesting 5.3.1 Intentional use: (subsistence/small scale) [harvest] 8 Invasive and other problematic species, genes & diseases 8.1 Invasive non-native/alien species/diseases 8.1.2 Named species

Threats

Major Threat(s):

As this species is epiphytic it is dependent on the presence of trees and or Xerophyta retinervis within the grassland areas, and there is ongoing habitat degradation of forested areas within the highveld grassland areas. The small forest patches within grassland are being degraded from logging and the spread of invasive alien Acacia species. Furthermore, repeated hot fires negatively impact the Xerophyta population causing slow ongoing decline to this species.

List of Threats:

5 Biological resource use
5.3 Logging & wood harvesting
5.3.1 Intentional use: (subsistence/small scale) [harvest]
8 Invasive and other problematic species, genes & diseases
8.1 Invasive non-native/alien species/diseases
8.1.2 Named species

Conservation Actions
Conservation Actions:	This species has currently not been recorded from within any protected areas, although it has been located within a proposed conservancy.
List of Conservation Actions:	1 Land/water protection 1.2 Resource & habitat protection 3 Species management 3.4 Ex-situ conservation 3.4.2 Genome resource bank

Bibliography
	Bachman, S., Moat, J., Hill, A.W., de la Torre, J. and Scott, B. 2011. Supporting Red List threat assessments with GeoCAT geospatial conservation tool. In: Smith V, Penev L (Eds) e-Infrastructure for data publishing in biodiversity science. . ZooKeys 150: 117-126. Mucina, L., Rutherford, M.C. and Powrie, L.W. (Editors). 2018. The Vegetation Map of South Africa, Lesotho and Swaziland. South African National Biodiversity Institute. Available at: http://bgis.sanbi.org/Projects/Detail/186.

Bibliography

Bachman, S., Moat, J., Hill, A.W., de la Torre, J. and Scott, B. 2011. Supporting Red List threat assessments with GeoCAT geospatial conservation tool. In: Smith V, Penev L (Eds) e-Infrastructure for data publishing in biodiversity science. . ZooKeys 150: 117-126.
Mucina, L., Rutherford, M.C. and Powrie, L.W. (Editors). 2018. The Vegetation Map of South Africa, Lesotho and Swaziland. South African National Biodiversity Institute. Available at: http://bgis.sanbi.org/Projects/Detail/186.

Citation: