Sphacanthus

{{Short description|Genus of plants}}

{{Automatic taxobox

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|taxon = Sphacanthus

|authority = Benoist (1939)

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Sphacanthus is a genus of flowering plants belonging to the family Acanthaceae. It includes two species endemic to Madagascar.{{cite web |title=Sphacanthus Benoist {{!}} Plants of the World Online {{!}} Kew Science |url=https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:942-1 |website=Plants of the World Online |access-date=19 May 2021 |language=en}}