Albany Quillwort

Taxonomy
Scientific Name
Isoetes wormaldii Sim
Higher Classification
Ferns
Family
ISOETACEAE
National Status
Status and Criteria
Critically Endangered C2a(i); D
Assessment Date
2007/03/02
Assessor(s)
J.E. Victor & A.P. Dold
Justification
This species has an area of occupancy (AOO) of less than 1 km² and is known from three, possibly four locations. It occurs as small subpopulations, each with a maximum of 15 plants. Subpopulations fluctuate in response to grazing (numbers increase after temporary pools are grazed). Without grazing, plants temporarily disappear. It is declining due to urban development and is therefore listed as Critically Endangered under criteria C and D.
Distribution
Endemism
South African endemic
Provincial distribution
Eastern Cape
Range
This species is found in Grahamstown.
Habitat and Ecology
Major system
Freshwater
Major habitats
Grahamstown Grassland Thicket, Crossroads Grassland Thicket
Description
Plants grow in temporary pools and streams or perennially submerged in slow-flowing rivers.
Threats
Urban spread and agricultural expansion has destroyed much of this species' habitat. The only known subpopulation occurs in a small wetland on a privately owned farm near Grahamstown. It was thought that cattle grazing the site was damaging and disturbing the species' habitat, but after the livestock was excluded from the wetland, the population disappeared. It therefore seems that trampling of the wetland in actual fact has a stimulating effect on the species and is required to maintain the population.
Population

This species is extremely rare and seldom seen. Monitoring of three subpopulations in the Grahamstown area recorded subpopulations disappearing for up to six years, only to reappear suddenly, possibly as a result of germination from dormant spores, under the right conditions. The average subpopulation size is about 10-15 mature individuals.


Population trend
Decreasing
Assessment History
Taxon assessed
Status and Criteria
Citation/Red List version
Isoetes wormaldii SimCR B2ab(i,ii,iii,iv,v)c(iv); C2a(i)b; DRaimondo et al. (2009)
Isoetes wormaldii SimEndangered Hilton-Taylor (1996)
Isoetes wormaldii SimUncertain Hall et al. (1980)
Bibliography

Cook, C.D.K. 2004. Aquatic and wetland plants of southern Africa. Backhuys Publishers, Leiden, The Netherlands.


Goldblatt, P. and Manning, J.C. 2000. Cape Plants: A conspectus of the Cape Flora of South Africa. Strelitzia 9. National Botanical Institute, Cape Town.


Hall, A.V., De Winter, M., De Winter, B. and Van Oosterhout, S.A.M. 1980. Threatened plants of southern Africa. South African National Scienctific Programmes Report 45. CSIR, Pretoria.


Hilton-Taylor, C. 1996. Red data list of southern African plants. Strelitzia 4. South African National Botanical Institute, Pretoria.


Raimondo, D., von Staden, L., Foden, W., Victor, J.E., Helme, N.A., Turner, R.C., Kamundi, D.A. and Manyama, P.A. 2009. Red List of South African Plants. Strelitzia 25. South African National Biodiversity Institute, Pretoria.


Sieben, E.J.J. 2009. The status and distribution of vascular plants (Magnoliophyta, Lycophyta, Pteridophyta). In: W.R.T. Darwall, K.G. Smith, D. Tweddle and P. Skelton (eds.), The status and distribution of freshwater biodiversity in southern Africa (pp. 83-98), IUCN and SAIAB, Gland, Switzerland and Grahamstown, South Africa.


Victor, J.E. and Dold, A.P. 2003. Threatened plants of the Albany Centre of Floristic Endemism, South Africa. South African Journal of Science 99:437-446.


Citation
Victor, J.E. & Dold, A.P. 2007. Isoetes wormaldii Sim. National Assessment: Red List of South African Plants version . Accessed on 2025/04/14

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Distribution map

© J.E. Burrows

© J.E. Burrows

© J.E. Burrows


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