In this paper, the first discovery of a stygobitic beetle in eastern Australia, from the Pages River and Dart Brook alluviums in the upper Hunter Valley, New South Wales is reported. 'Carabhydrus stephanieae' sp. nov. (Dytiscidae, Hydroporini) is described and figured. An analysis of the complete tRNA-leu gene, part of the 16S ribosomal RNA gene and part of the NADH dehdrogenase subunit 1 gene was used to assess its relationship with congeneric surface species.