It seems I don’t need to write an encyclopedia of the Polity. Here’s the start of a piece on the Prador over at Wikipedia:

Physical description

Prador are amphibious crustaceans with flattened pear-shaped shells with scalloped rims and a raised visual turret at the broad end that houses several pairs of red spider-like eyes, some of which are on movable stalks. Prador move about on six long legs, each terminating in a wicked spike. The rear pair of legs fall off when adolescent Prador make the transition to adults, exposing their sexual organs in the process. Along their underside Prador have four manipulatory arms, each ending in a hand described as “a complex arrangement of hooks and fingers”. These hands are highly dexterous and capable of fine manipulation, just like a human hand. It appears Prador can use all four hands to perform different tasks simultaneously, such as drawing and firing four different weapons at separate targets. Above these are the two heavy “working claws”; large crab-claw limbs that can easily cut through tough materials and crush human bones. Prador feed with a set of dangerous mandibles, capable of grasping, cutting and chewing flesh. Prador are carnivorous, and mostly feed on decaying flesh, primarily harvested from giant mudskippers farmed on their homeworld. Adult Prador are very fond of human flesh, however, and many humans are bred just for this purpose, although by the end of the book The Skinner, this practice has begun to decline. Prador shells are particularly tough, able to withstand impacts and small arms fire, but they seem quite vulnerable to energy weapons and heat, which can cause the shells to burst open.And here’s their entry about me.