Two motile actinomycete strains, K95-5561T and K95-5562, were isolated from a soil sample collected at Sayama City, Saitama Prefecture, Japan. They produced bell shaped spore vesicles (sporangia) with hairy surfaces on substrate hyphae. When released into water, the sporangiospores became motile by a tuft of polar flagella. The chemotaxonomic and morphological characteristics together with 16S rRNA gene sequence data indicated that the two isolates belonged to the genus Actinoplanes. The two strains were assigned to a single species on the basis of phenotypic, notably cultural, morphological and physiological characteristics, and DNA-DNA pairing data. The two strains were distinguished from representatives of all validly described species of Actinoplanes using a combination of genotypic and phenotypic properties. It is, therefore, proposed that strains K95-5561 and K95-5562 be recognized as a new species of the genus Actinoplanes with the name Actinoplanes capillaceus sp. nov. The type strain of the species is strain K95-5561T (=JCM 10268T =IFO 16408T). The invalidly proposed species 'Ampullariella cylindrica', 'Ampullariella pekinensis' and 'Ampullariella pilifera' were assigned to Actinoplanes capillaceus on the basis of genotypic and phenotypic data.