Great Geckobugs, like most hectapedes, have seven legs and an extendable jaw. These, though, belong to a lunged group, enabling them to retrieve the oxygen necessary for their active lifestyles and large bodies. They are a foot long, and the pads of their feet contain hundreds of tiny hairs like a gecko's. This earns them both their name and their ability to stick to walls. Unlike a gecko, their seven feet mean they have more support points, enabling them to move faster on a wall than a gecko of the same size. They grow to a foot long. There are many colours, but the non-domesticated Great Geckobugs have a shiny carpace like a jewel bug's. The most common colours in captivity are green, amber and black. They can make a range of sounds, such as chirps, hisses, barks and roars.
Sgarpos have a keen sense of smell, an ability to get into many places, and have strong armour. Due to this, they are often used to help detect chemicals, such as drugs or explosives. There is a practice, illegal on many planets, that is equivalent to cock-fighting or badger baiting. The Great Geckobug is also used as a rat-equivalent-catcher, due to its extendable jaw and great adaptability. The Irkaputh have domesticated the pre-domesticated Urahob sgarpos to use as steeds.