Taxonomy
Scientific Name
Thereianthus bulbiferus Goldblatt & J.C.Manning
Higher Classification
Monocotyledons
Family
IRIDACEAE
National Status
Status and Criteria
Endangered B1ab(i,ii,iii,iv,v)+2ab(i,ii,iii,iv,v)
Assessment Date
2014/04/22
Assessor(s)
L. von Staden & D. Raimondo
Justification
EOO 760 km², between one and three remaining locations continue to decline due to ongoing habitat loss, fragmentation and degradation.
Distribution
Endemism
South African endemic
Provincial distribution
Western Cape
Range
Piketberg to Gouda and Paarl.
Habitat and Ecology
Major system
Terrestrial
Major habitats
Swartland Shale Renosterveld, Swartland Silcrete Renosterveld, Swartland Alluvium Fynbos
Description
Seasonally wet alluvial flats.
Threats
Less than 30% of alluvial fynbos remains intact after extensive loss to crop cultivation, as well as urban expansion. Loss continues, and remaining fragments continue to be degraded, and are often too infrequently burnt - this species relies on fire to flower.
Population

This range-restricted species is seldom collected, and the extent and size of the population is difficult to estimate, as this species flowers most prolifically after fire, and is very rare in the intervening time (Manning and Goldblatt 2011). There is currently only one known existing subpopulation, which is protected within a private nature reserve. Two other subpopulations were recorded with imprecise locality detail from areas now extensively modified for crop cultivation, and may be locally extinct. Due to its fire-stimulated flowering, it is likely to be overlooked, but with less than 30% of alluvial fynbos remaining within this species' known range, it is unlikely that many undiscovered subpopulations remain.


Population trend
Decreasing
Assessment History
Taxon assessed
Status and Criteria
Citation/Red List version
Thereianthus bulbiferus Goldblatt & J.C.ManningEN B1ab(i,ii,iii,iv,v)+2ab(i,ii,iii,iv,v)2014.1
Bibliography

Manning, J.C. and Goldblatt, P. 2011. Taxonomic revision of the genus Thereianthus (Iridaceae: Crocoideae). Bothalia 41(2):239-267.


Citation
von Staden, L. & Raimondo, D. 2014. Thereianthus bulbiferus Goldblatt & J.C.Manning. National Assessment: Red List of South African Plants version 2020.1. Accessed on 2021/09/21

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Distribution map

© J.C. Manning


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