Scadoxus membranaceus was named by John Gilbert Baker in 1888, as Haemanthus membranaceus. He later described this species as a variety of Haemanthus puniceus (which is the current Scadoxus puniceus). The meaning of the generic epithet is unclear and never explained, but doxus means ‘glorious’ in Greek and sca means ‘obscure’. Membranaceus describes the membranous outer texture of the spathe bracts.

The genus Scadoxus, in the amaryllis family, consists of 9 species that are distributed throughout tropical Africa. Three of the 9 species are found in the summer-rainfall region of South Africa and 2 are found in the winter-rainfall Western Cape. For a long time this genus was regarded as a subgenus of Haemanthus. The separation of this genus from Haemanthus was done by Constantine Samuel Rafinesque in 1838, when he moved Haemanthus multiflorus to Scadoxus multiflorus. The separation of the 2 genera was ignored by many, until 1976, when Scadoxus was again segregated from Haemanthus by Ib Friis and Inger Nordal. The difference between them is that species of Haemanthus form true bulbs and have sixteen chromosomes, whereas species of Scadoxus do not all form bulbs and have eighteen chromosomes. In Scadoxus the rootstock is basically an elongated rhizome with a bulbous part above it. The leaves have a distinct midrib, which is not present in Haemanthus, which remains dry or green during flowering. In some plants the sheath looks like a stem. Another distinction which was found was that Haemanthus species are all native to southern Africa, whereas most species of Scadoxus are found in tropical Africa.