Simple SummaryA new species of snail-eating snake in the genusPareasis described, from the Youjiang District, Baise City, Guangxi Zhuang Autonomous Region, China, based on one male and three juvenile specimens. The maximum likelihood analyses based onCytochrome b(Cyt b) andNADH dehydrogenase subunit 4(ND4) indicated the new taxon is different from its congeners. Morphologically, the new species can be diagnosed from the other species by a combination of seven characters. The recognition of the new species brings the number of describedPareasspecies to 30.AbstractWe described a new species of genusPareasfrom Baise City, Guangxi Zhuang Autonomous Region, China, based on morphological and molecular evidence.Pareas baiseensissp. nov. is distinguished from its congeners by the combination of (1) Yellowish-brown body colouration; (2) Frontal subhexagonal to diamond-shaped with its lateral sides converging posteriorly; (3) The anterior pair of chin shields is longer than it is broad; (4) Loreal not in contact with the eye, prefrontal in contact with the eye, two or three suboculars; (5) Rows of 15–15–15 dorsal scales, five rows of mid-dorsal scales keeled at the middle of the body, one vertebral scale row enlarged; (6) 187–191 ventrals, 89–97 subcaudals, all divided, cloacal plate single; (7) Two postocular stripes, the nuchal area forming a dark black four-pointed fork collar with the middle tines shorter than the outside tines. The genetic divergence (uncorrectedp-distance) between the new species and other representatives ofPareasranged from 13.9% to 24.4% forCytochrome b(Cyt b) and 12.1% to 25.5% forNADH dehydrogenase subunit 4(ND4). Phylogenetic analyses of mitochondrial DNA gene data recovered the new species from being the sister taxon to (P. boulengeri + P. chinensis) from China.