Gephyroberyx darwinii, the big roughy or Darwin's slimehead, is a species of fish in the slimehead family found widely in the Atlantic and Indo-Pacific oceans. This deep-sea species reaches a length of 60cm (20inches) and is mainly found at depths of 200to(-), but has been recorded between 9and(-). Based on broadly overlapping morphological features it sometimes (e.g., by IUCN) includes G. japonicus as a synonym.[1]