Senecio namibensis (Asteraceae: Senecioneae), a new species from Namibia

WESSEL SWANEPOEL; ROLF BECKER; VERA DE CAUWER; ABRAHAM E. VAN WYK

doi:10.11646/phytotaxa.571.2.1

Issue: Vol. 571 No. 2: 3 November 2022

Type: Article

Published: 2022-11-03

DOI: 10.11646/phytotaxa.571.2.1

Page range: 103-111

Abstract views: 49

PDF downloaded: 25

Senecio namibensis (Asteraceae: Senecioneae), a new species from Namibia

WESSEL SWANEPOEL⁺⁻
ROLF BECKER⁺⁻
VERA DE CAUWER⁺⁻
ABRAHAM E. VAN WYK⁺⁻

Independent Researcher, P.O. Box 21168, Windhoek, Namibia. H.G.W.J. Schweickerdt Herbarium, Department of Plant and Soil Sciences, University of Pretoria, Pretoria, 0002 South Africa.

Biodiversity Research Centre, Department of Agriculture and Natural Resources Sciences, Namibia University of Science and Technology, Private Bag 13388, Windhoek, Namibia.

H.G.W.J. Schweickerdt Herbarium, Department of Plant and Soil Sciences, University of Pretoria, Pretoria, 0002 South Africa; South African National Biodiversity Institute, Private Bag X101, Pretoria, 0001 South Africa

endemism flora Kaokoveld Centre of Endemism Namib Desert Senecio englerianus Senecio flavus succulent taxonomy Eudicots

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Abstract

Senecio namibensis is described as a new species known only from the northern part of the Namib Desert in northwestern Namibia. It is a range-restricted species near-endemic to the Kaokoveld Centre of Endemism. These dwarf shrubs grow on rocky outcrops under harsh desert conditions. Diagnostic characters for Senecio namibensis include the annual or perennial habit, succulent leaves, and radiate capitula with 3–6 yellow ray florets. A comparison of some of the more prominent morphological features to differentiate between S. namibensis and its possible nearest relatives, S. englerianus and S. flavus, is provided. All three species have superficially similar looking succulent leaves, but an obvious difference is that the capitula in S. englerianus are discoid and in S. flavus disciform or obscurely radiate. Based on IUCN Red List categories and criteria, a conservation assessment of Least Concern (LC) is recommended for the new species.

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