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A Gram-stain-negative, aerobic, rod-shaped, beige bacterium, strain B717-2(T), was isolated from an ice core drilled from Murtagh Glacier on the Tibetan Plateau, China. According to phylogenetic analyses based on 16S rRNA gene sequences, the novel strain was related most closely to Polaromonas vacuolataand shared 97.7% similarity with the type strain of this species. It grew optimally at pH 7, at 15 degrees C and with 2% (w/v) NaCl. Major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. The major fatty acids were summed feature 3 (C-16:1 omega 7c and/or iso-C-15:0 2-OH), summed feature 8 (C-18:1 omega 7c, C-18:1 omega 6c) and C-16:0. The sole respiratory quinone was Q-8. The DNA G+C content was 63.4 mol %. In DNA-DNA hybridization tests, strain B717-2(T) shared 37.0 +/- 1.9, 30.0 +/- 1.7, 26.0 +/- 0.9, 23.4 +/- 0.5 and 18.4 +/- 1.9% DNA-DNA relatedness with Polaromonas jejuensisJS12-13(T), P. vacuolata 34-P-T, Polaromonas aquatica CCUG 39402(T), Polaromonas glacialisCr4-12(T) and Polaromonas cryoconitiCr4-35(T), respectively. Based on the phenotypic, phylogenetic and genetic characteristics, strain B717-2(T) represents a novel species of the genus Polaromonas, for which the name Polaromonaseurypsychrophila sp. nov. is proposed. The type strain is B717-2(T) (=CGMCC 1.15322(T)=JCM 31171(T)).