The Identity of the Massawa Aloe

Abstract

Summary. Aloe populations from Eritrea and Tanzania, formerly considered to represent a single species, are shown to be different and a new name, Aloe eumassawana, is provided for the Eritrean plants. The original records of the Massawa Aloe, Aloe massawana Reynolds, were from around the town of "Massawa" (the modern spelling is Mits'iwa) on the Red Sea coast of Eritrea and from Tanzania, again along the coast. The records from Tanzania were of plants associated with old Arab graves. Reynolds (1966), who had seen no wild populations in East Africa, named the species after the locality of the Red Sea plants but chose a type from the Tanzanian coast, supposing that the grave plants had been brought by ship from near "Massawa". Closer examination does not support this view, and has shown that 2 closely related but distinct taxa are involved, differing in details of leaf width (narrower - 6 - 10 cm in the East African material), flower length (longer - 25 - 32 mm in the East African material), with the outer perianth lobes joined for distinctly different proportions of their length (less than half as opposed to c. two thirds in the East African material), and, probably most significantly, in inflorescence indumentum (the East African material is completely glabrous whilst Eritrean inflorescences are minutely puberulent). There also seems to be a difference in habit between the two plants: the East African plants do not form large clumps and have more distinctly spreading to recurved leaves whereas the Massawa plant suckers very freely to form extensive clumps and has erect to slightly incurved leaves. These differences seem to separate the two groups quite consistently and adequately. Further fieldwork has shown that A. massawana sensu stricto occurs in natural situations, well away from settlements, along the coasts of Tanzania and northern Mozambique and that there is no need to suppose that the grave plants had been brought from so far afield. This was first noted by Carter (1994: 24) and has been confirmed by a recent collection from Eritrea by Dr and Mrs Hillman. Unfortunately the selection of a Tanzanian collection as the type of A. massawana by Reynolds means that the epithet must remain attached to the East African plants, however misleading this might be, and that the Red Sea plants need describing as a new species. We have chosen the epithet "eumassawana" - "true massawana" - in an attempt to draw attention to this misleading situation.