Crymostygidae, a new family of subterranean freshwater gammaridean amphipods (Crustacea) recorded from subarctic Europe

Abstract

Crymostygidae, a new family of gammaridean amphipods (Crustacea), is described from Iceland. The family is based on a new species and genus, Crymostygius thingvallensis, found in spring inlets feeding Lake Thingvallavatn, south-west Iceland. This is the first report of a stygobiont freshwater amphipod from Iceland and the northern-most report of a stygobiont species in Europe. The species apparently survived Pliocene and Pleistocene glaciations in the groundwater of a porous lava and may have persisted in Iceland for several million years.

Keywords:

• Crymostygius thingvallensis
• Iceland
• stygobiont
• groundwater
• Ice-age survival
• Crymostygidae
• Crangonyctoidea

Acknowledgements

We wish to thank all those that assisted in many attempts to collect more specimens of the species. We thank John Holsinger, Agnar Ingólfsson, Niel L. Bruce and Svavar Hrafn Svavarsson for their valuable comments and advice. The Icelandic Research Council supported the study.