Reappraisal and identification of Olinia rochetiana (Oliniaceae) in South Africa

Abstract

A numerical phenetic analysis of data obtained from populations of the Olinia rochetiana A.Juss. complex occurring in South Africa (Mpumalanga and Limpopo Provinces) revealed the existence of two forms: 1, a shrubby form (up to 2.5 m tall), with thick terminal branches, coriaceous leaves with a tinge of red on margins (towards the apices),short inflorescence axes, peduncles and deeply red pedicels and floral tubes/hypanthia: and 2, a slender tree form, measuring more than 4 m tall with slender terminal branches, glossy and slightly thin, papery leaves, margin colour the same as the entire lamina, and the inflor­escence axes, peduncles, pedicels and hypanthia pale green to creamy white. Differences in floral features between the twoforms correlate with differences observed in vegetative features. The two forms occupy distinct ecological niches and show tolerances and preferences for different environmental conditions such as soil type,elevation and humidity. An identificationkey for the two forms is presented.