The subarctic ancient Lake El'gygytgyn harbours the world's northernmost 'limnostygon community' and reshuffles crangonyctoid systematics (Crustacea, Amphipoda).

The northward distribution limit of groundwater fauna is generally dictated by the extent of glacial ice sheets during the Pleistocene. However, some taxa can be found far above this limit, sometimes on isolated oceanic islands, implying long-term survival in subglacial subterranean refugia. Here we report a peculiar assemblage comprising two new depigmented and blind (stygomorphic) amphipods from the subarctic ancient lake El'gygytgyn (northern Far East): Palearcticarellus hyperboreus sp.