Taxonomy
Scientific Name
Isoetes aequinoctialis Welw. ex A.Braun
Higher Classification
Ferns
Family
ISOETACEAE
Synonyms
Calamaria aequinoctialis (Welw. ex A.Braun) Kuntze, Isoetes erongoensis Wanntorp
National Status
Status and Criteria
Data Deficient - Insufficient Information
Assessment Date
2011/11/29
Assessor(s)
J.E. Burrows & L. von Staden
Justification
Rare, and very poorly known within South Africa. Not enough is currently known about this species' population status and trends within South Africa to determine its status.
Distribution
Endemism
Not endemic to South Africa
Provincial distribution
Free State, Mpumalanga, Northern Cape
Range
Known from only a few scattered records within South Africa, and rare elsewhere in southern Africa and northwards to tropical Africa.
Habitat and Ecology
Major system
Freshwater
Major habitats
Grassland, Nama Karoo
Description
Seasonally moist depressions and pans in hot, arid savanna woodland.
Threats
Unknown.
Population

An extremely rare species with a scattered distribution that may also be overlooked. Until the 1990s, it was known from a single record from the Northern Cape (Burrows 1990, Hilton-Taylor 1996), and a few scattered records from arid savanna in Namibia, Angola and Zimbabwe. The source of the Northern Cape locality however cannot be traced, and the specific locality details are unknown. A recent publication (Crouch et al. 2011) indicate two additional South African localities from high altitude montane grasslands in the Free State and Mpumalanga, a habitat completely different from other known records of this species, and at least the Mpumalanga locality is probably a misidentification of Isoetes welwitschii (J.E. Burrows pers. comm.). This species is quite likely overlooked, and in addition, the genus is taxonomically problematic and under revision (J.P. Roux pers. comm.), and currently this species' population status and trends within South Africa cannot be adequately evaluated.


Population trend
Unknown
Assessment History
Taxon assessed
Status and Criteria
Citation/Red List version
Isoetes aequinoctialis Welw. ex A.BraunVU D22011.1
Isoetes aequinoctialis Welw. ex A.BraunVU D2Raimondo et al. (2009)
Isoetes aequinoctialis Welw. ex A.BraunExtinct Hilton-Taylor (1996)
Bibliography

Burrows, J.E. 1990. Southern African ferns and fern allies. Frandsen Publishers, Sandton.


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


Crouch, N.R., Klopper, R.R., Burrows, J.E. and Burrows, S.M. 2011. Ferns of southern Africa: A comprehensive guide. Struik Nature, Cape Town.


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


Pfeiffer, N.E. 1922. Monograph of the Isoetaceae. Annals of the Missouri Botanical Garden 9:79-232.


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.


Schelpe, E.A.C.L.E. 1970. Pteridophyta. In: A.W. Exell and E. Launert (eds). Flora Zambesiaca:1-254. Crown Agents for Oversea Governments and Administrations, London.


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.


Citation
Burrows, J.E. & von Staden, L. 2011. Isoetes aequinoctialis Welw. ex A.Braun. National Assessment: Red List of South African Plants version . Accessed on 2025/04/14

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Distribution map


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