Whalefishes, bignoses and tapetails – these three groups of deep-sea fishes couldn’t look more different. The whalefishes (Cetomimidae) have whale-shaped bodies with disproportionately large mouths, tiny eyes, no scales and furrowed lateral lines – narrow organs on a fish’s flanks that allow it to sense water pressure. The tapetails (Mirapinnidae) are very different – they…