Spotted Ratfish, Hydrolagus colliei


The Spotted Ratfish is a type of chimaera found in the northeastern Pacific Ocean. Although it is not very large, it has a fearsome bite due to its sharp dental plates which it has instead of teeth, an adaptation due to its diet of crustacea. It also has a venomous spine in front of its dorsal fin. If it feels as though its territory is threatened in any way, it will swim towards the intruder in a corkscrew fashion with the aim of injecting a mildly toxic venom. It mainly lives in deep water although it sometimes comes into relatively shallow waters.


The purpose of this illustration is species identification; showing precision and clarity is vital, e.g. separating the spine from the dorsal fin and number of fins etc. As I did not have access to the holotype (the individual species from which the species description is derived), I used a lot of visual references in addition to the many species descriptions. From the multitude of photographs, I got the proportions in percentile form. After I had a proportional preliminary sketch, I transferred the image to coquille paper and used a black Prismacolour pencil for shading. The beauty of this paper is that it gives a stipple effect, which is great for subjects with textures or patterns. As this fish has a spotted pattern and variable colour and tone, this method worked effectively and efficiently. Since the Prismacolour can only get so dark, I used ink (Micron pen works great) to darken the edges and add some stipple for added contrast. As with all my pieces, once I scanned it in I corrected the black and white and amped up the contrast.