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Issue: Vol. 784 No. 2: 12 Nov. 2026
Type: Article
Published: 2026-11-12
DOI: 10.11646/phytotaxa.784.2.4
Page range: 188-200
Abstract views: 64
PDF downloaded: 20

Petalidium matupaense (Acanthaceae), a new species from Angola

1Independent Researcher; P.O. Box 21168; Windhoek; Namibia; 2H.G.W.J. Schweickerdt Herbarium; Department of Plant and Soil Sciences; University of Pretoria; Pretoria; 0002 South Africa; 3Ongava Research Centre; Private Bag 12041; Windhoek; Namibia; 4Biodiversity Research Centre; Department of Agriculture and Natural Resources Sciences; Namibia University of Science and Technology; Private Bag 13388; Windhoek; Namibia
2H.G.W.J. Schweickerdt Herbarium; Department of Plant and Soil Sciences; University of Pretoria; Pretoria; 0002 South Africa; 5South African National Biodiversity Institute; Private Bag X101; Pretoria; 0001 South Africa
Eudicots Cunene Province endemism Kunene Anorthosite Complex Oncocua Ruellieae Serra Matupa taxonomy ultramafic rocks Zebra Mountains

Abstract

Petalidium matupaense, first collected in May 2019, is here described as a new species. It is a range-restricted species, only known from the mountainous region bordering the Cunene River in southwestern Angola in the Kaokoveld Centre of Endemism. The species grows amongst boulders on hillsides of the Kunene Igneous Complex, along ephemeral riverbeds and in intermontane valleys. Diagnostic characters for P. matupaense include its slender stems and the dense white indumentum of mainly short-stalked dendritic trichomes on the vegetative parts (glabrescent with age) and inflorescences, giving a matted appearance. The flowers are distinctive in having all lobes similarly coloured adaxially, carmine, peach, vermillion (orange-red), or mauve, the anterior lobe with two yellow narrowly triangular nectar guides, and all lobes discolorous in being abaxially paler or cream-brown. A comparison of key morphological features distinguishing Petalidium matupaense from P. cirrhiferum and P. sebrabergense, its morphologically most similar relatives, is provided. Based on IUCN Red List criteria, the species is provisionally assessed as Endangered (EN).

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How to Cite

Swanepoel, W. & Wyk, A.E.V. (2026) Petalidium matupaense (Acanthaceae), a new species from Angola. Phytotaxa 784 (2): 188–200. https://doi.org/10.11646/phytotaxa.784.2.4