The type strains of 33 Actinomadura, 2 Excellospora, and 4 Microtetraspora species, together with those of Microbispora echinospora and Nocardiopsis africana, were assigned to two aggregate groups that merited generic status given chemical, molecular and numerical taxonomic evidence. The aggregate taxa corresponded with the genera Actinomadura and Microtetraspora as; emended. The emended genus Actinomadura showed its closest affinty to Thermomonospora and Microtetraspora to the genera Microbispora, Planobispora, Planomonospora and Streptosporangium. It is proposed that Actinomadura coeruleoviolacea be transferred to the genus Saccharothrix as Saccharothrix coeruleoviolacea comb. nov. Further studies are required to establish the taxonomic status of Actinomadura aurantiaca and Actinomadura carminata. The revised genus Actinomadura encompasses Actinomadura atramentaria, Actinomadura citrea, Actinomadura coerulea, Actinomadura cremea, Actinomadura fibrosa, Actinomadura fulvescens, Actinomadura kijianata, Actinomadura libanotica, Actinomadura livida, Actinomadura luteofluorescens, Actinomadura macra, Actinomadura madurae (the type species), Actinomadura oligospora, Actinomadura pelletieri, Actinomadura spadix, Actinomadura umbrina, Actinomadura verrucosospora, Actinomadura vinacea, Actinomadura viridis (including Actinomadura malachitica) and Actinomadura yumaensis. It is proposed that Microbispora echinospora and Excellospora rubrobrunea nom. rev. be transferred to the emended genus Actinomadura. It is also proposed that Actinomadura fastidiosa, Actinomadura ferruginea, Actinomadura flexuosa, Actinomadura helvata, Actinomadura polychroma, Actinomadura pusilla, Actinomadura recticatena, Actinomadura roseola, Actinomadura roseoviolacea, Actinomadura rubra, Actinomadura salmonea, Actinomadura spiralis and Actinomadura turkmeniaca, Micropolyspora angiospora and Nocardiopsis africana be transferred to the revised genus Microtetraspora. © 1990, Gustav Fischer Verlag, Stuttgart · New York. All rights reserved.
