Sepia cultrata has a pale buff pinkish brown colouring. The club is crescent shaped with a flattened sucker bearing possessing 5 or 6 small suckers in transverse rows.
The cuttlebone of the knifebone cuttlefish is elongate oval; with a characteristic triangular pointed anterior end, while the posterior end is narrow. The dorsal surface is salmon coloured with a distinct narrow median rib and two faint lateral ribs.
This is a deep water species with the majority of catches occurring at 300 to 500 m depth, although the species has been found between depths of 132 to 803 metres.
The knifebone cuttlefish is found in the Southern Indo-Pacific and is distributed in southern Australian coastal waters from southern Queensland to Western Australia, including Tasmania.
- Jereb, P., & C.F.E Roper (eds) (2005) Cephalopods of the World: Chambered Nautiluses and Sepioids, Food & Agriculture Organization of the United Nations Catalogue for Fishery Purposes, Rome, No. 4, Vol. 1
- Lu, C.C (1998) A Synopsis of Sepiidae in Australian waters (Cephalopoda: Sepiodiea). In: Voss, N.A., Vecchione, M., Toll, R.B. & Sweeney, M.J (Eds) Systematics and Biogeography of Cephalopods. Smithsonian Institution Press, Washington DC, Vol. 586, 159-190.
- Watson-Russell, C. (1983) Cuttlefish of Sydney Harbour, Australian Natural History, 20(5): 159-164.