A new species of liparid fish of the genus Paraliparis (Cottoidei, Liparidae) from the bathyal depth of the South Atlantic Ocean

Liparid fishes, found in the cold and temperate waters of all oceans, inhabit areas from coastal zones to ultra-abyssal depths. The genus Paraliparis Collett, 1879 includes more than 140 species, mostly bathypelagic. The Zoological Institute of the Russian Academy of Sciences acquired a specimen of Paraliparis, caught at a depth of 1470 m in the area of the Burdwood Bank, located in the South Atlantic south of the Falkland Islands. Analysis of the liparid fauna of the region showed that 20 species of the genus are known off the southern part of South America and in the adjacent Subantarctic waters. Comparative study revealed that among all congeners from the region, the specimen is most similar to one of them, P. gracilis Norman, 1930 – in counts of vertebrae and pectoral-fin rays, and in the absence of pyloric caeca. However, differences are also present indicating the specimen represents a new species. We provide a description of a new species, Paraliparis bathypelagicus sp. nov., which differs from congeners by a combination of characters: vertebrae 68, pectoral-fin rays 16, dorsal-fin rays 61, anal-fin rays 57, caudal-fin rays 6; pyloric caeca absent, multi-row teeth; gill slit reaching to level of uppermost pectoral-fin ray; dorsal side of head and body pale, underside of head and belly inky black, tail part pigmented. If the South Georgian P. gracilis is distributed within the Subantarctic zoogeographic region at depths of 120–830 m, then P. bathypelagicus sp. nov. apparently belongs to the bathypelagic fauna of the Patagonian region of the South Atlantic and inhabits considerably deeper zone. We assume that these two are paired species, having diverged in two geographically adjacent but ecologically distinct regions.