Source: Souls for Smuggler's Shiv, pg(s). 78-79
The ochre eurypterid is the smallest-known variety of eurypterid, generally growing no larger than a hunting or guard dog. Despite their small stature, they are still aggressive hunters, and will attack anything they perceive as a source of food. Since they do not generally damage cargo or carry diseases, they are occasionally used by adventurous ship's crews to control the ever-present vermin problem.