Aloe tomentosa – a species with unusual hairy flowers from the Yemen

CactusWorld 2016 Vol. 34 (3) Aloe is a large genus of over 500 species (Carter et al, 2011) and even today that number continues to increase. Of these, a very small number of species, perhaps no more than 20, are unusual in having hairy flowers. These are concentrated in southern Arabia and the Horn of Africa. In respect of Saudi Arabia, for example, Collenette (1999) records 22 species of Aloe and two hybrids. Three of the Saudi aloes have hairy flowers, which represents only 12.5% of the total number of aloes recorded for this large country. In Oman, Miller et al (1988) record no aloes with hairy flowers. Further south in mainland Africa, Sebsebe Demissew & Nordal (2010) accept six species out of 46 with hairy flowers for Ethiopia and Eritrea, making 13% of that total. For the small adjacent country of Djibouti, Ruch et al (2013) recognise that nearly half the species, ie four out of a total of nine (44%), are hairy-flowered species. Further east in Somalia, Lavranos (1995) similarly identifies four species with hairy flowers, but this represents only 12.9% of the total of 31 recognised species in this larger country. The most recently described hairyflowered Somali species is Aloe anodonta T.A.McCoy & Lavranos (McCoy & Lavranos, 2015). The furthest south that hairy-flowered aloes have been recorded on the African continent is northern Kenya: Aloe citrina S. Carter & Brandham (Carter et al, 2011). Madagascar, with its great diversity of aloes, currently totalling perhaps 150 taxa, has no hairy-flowered species at all (Castillon & Castillon, 2010).