A bacterial strain designated GFC-1(T) was isolated from a fish-culture pond in Taiwan and was characterized by using the polyphasic taxonomic approach. Strain GFC-1(T) was Gram-negative, aerobic, rod-shaped, motile and non-spore-forming. Phylogenetic analyses based on 16S rRNA gene sequences showed that the strain belonged to the genus Andreprevotia of the family Neisseriaceae and its closest neighbour was Andreprevotia chitinilytica JS11-7(T) (97.0 % sequence similarity). The results of physiological and biochemical tests allowed clear phenotypic differentiation of isolate GFC-1(T) from A. chitinilytica JS11-7(T). The major fatty acids were summed feature 3 (C(16 : 1)omega7c and/or iso-C(15 : 0) 2-OH), C(16 : 0) and C(18 : 1)omega7c. The DNA G+C content was 63.0 mol%. On the basis of 16S rRNA gene sequence analysis and chemotaxonomic and physiological data, strain GFC-1(T) should be classified as representing a novel species and a second member of the genus Andreprevotia, for which the name Andreprevotia lacus sp. nov. is proposed. The type strain is GFC-1(T) (=BCRC 17832(T)=LMG 24502(T)).