A moderately thermophilic bacterial strain designated wcf1(T), isolated from a hot spring located in the Tainan area, southern Taiwan, was characterized using a polyphasic approach. The cells were Gram-negative, non-pigmented, rod-shaped, non-spore-forming and motile. Phylogenetic analysis using 16S rRNA gene sequences showed that the strain formed a monophyletic branch towards the periphery of the evolutionary radiation occupied by the genus Schlegelella; its only close neighbour was the type strain of Schlegelella thermodepolymerans, K14(T) (97.8 %). The isolate was clearly distinguishable from other strains using phylogenetic analysis, DNA-DNA hybridization, fatty acid composition data and a range of physiological and biochemical characteristics. It was evident from the genotypic and phenotypic data that strain wcf1(T) represents a novel species in the genus Schlegelella, for which the name Schlegelella aquatica sp. nov. is proposed, with the type strain wcf1(T) (=BCRC 17557(T)=LMG 23380(T)).