A Remarkable New Species of Notobuxus (Buxaceae) from Tanzania

Abstract

In a set of duplicates of the collections of the egregious A. Peter received at Kew early in 1980 from Berlin, where they had reposed unharmed in a basement during the War, were two gatherings of a shrub from the East Usambaras with opposite, cordate, subamplexicaul leaves labelled 'Memecylon'. Rejected by my colleague G. E. Wickens from the Memecylaceae in favour of the Euphorbiaceae or something near it, it transpired that it was in fact Buxaceous, and that it belonged to the genus Notobuxus on account of its having 6 sessile anthers and no pistillode in the C flowers; all the other species of this genus have the leaves cuneate at the base, however. Cordate leaves are not unknown elsewhere in the family, but they are rather uncommon. The representation of the Buxaceae in the Flora of Tropical East Africa area is thus doubled, N. obtusifolia Mildbr. being the only member hitherto recorded (Verdcourt, 1962). Although in 1963 Hutchinson (MS note) expressed the opinion that 'Notobuxus now seems hardly separable from Buxus', the author prefers to follow Verdcourt (1965) who felt that it is convenient to retain Notobuxus since it is a group with a decisive character coupled with a distinctive distribution. The new species, having not only the decisive character of Notobuxus but also falling within its range of distribution, is accordingly described herein under that head, with an obvious choice of epithet: