Aerangis, Reichenbach, 1865

Cribb, Phillip & Carlsward, Barbara, 2012, New combinations in Aerangis, Diaphananthe and Podangis (Orchidaceae, subtribe Angraecinae), Phytotaxa 71 (1), pp. 42-47 : 43

Aerangis and Microterangis

Senghas (1985, 1986) separated the Malagasy and Comorian species previously ascribed to Chamaeangis to his new genus Microterangis , which he distinguished by its pollinarium structure with the pollinia attached to a single tegula (stipe) rather than each pollinium being attached to its own tegula. Otherwise, he recognized Microterangis in the same key couplet as Aerangis , distinguishing the former by its smaller yellow, green or orange, rather than predominantly white, flowers. He acknowledged the similarity of Microterangis to Aerangis in the name he chose. Szlachetko (2003) illustrated the floral structure of both Aerangis and Microterangis , showing their similarity in column, stigma, rostellum and pollinarium shape. Flower colour is also not as clear-cut as Senghas (1985, 1986) suggested because some of the smaller-flowered Aerangis species have a pale yellow or green perianth and even the larger-flowered ones have a white perianth variously flushed with pink, salmon-pink, brown or green.

Carlsward et al. (2006) included 16 species of Aerangis and two of Microterangis , including the type species, M. hariotiana ( Kraenzlin 1897a: 153) Senghas (1985: 22) , in their DNA-based analyses of vandaceous orchids. The Microterangis species were nested within Aerangis , sister to the Malagasy species, A. punctata Stewart (1986: 1121) . It seems likely that Microterangis are just small-flowered species of Aerangis that evolved in the Comoros or northern Madagascar from a common ancestor of larger-flowered Malagasy Aerangis .