Stygobromus canadensis, a new subterranean amphipod crustacean (Crangonyctidae) from Canada, with remarks on Wisconsin refugia

Abstract

Stygobromus canadensis, new species, is described from Castleguard Cave, a large alpine cave located in the Canadian Rockies of Alberta. This is the first subterranean amphipod crustacean reported from Canada and the ninth member of the genus found north of the southern limits of Pleistocene glaciation. Considering the evidence against postglacial dispersal (e.g., endemicity and lack of close affinity with species living farther south), and the presence of a subterranean isopod in the same cave, it is hypothesized that these small aquatic crustaceans survived the Wisconsin glaciers in deep, groundwater refugia under the ice. There is some evidence to suggest that Castleguard Cave, itself, could have served as such a refugium.