Night on the ground on Skull Island is a dangerous time and place to be if you are small. Among the invertebrate predators, few have mouthparts that can compete with those of the moonspider. A variety of sun spider, not a true spider, the ten-legged moonspider sports huge crushing scissor chelicerae and paralytic venom to make short work of its prey. Rodents (namely Skull Island Rats), lizards, small ground birds, and even non-avian dinosaur chicks are potential victims. A bite from the sizable arachnid can cause significant discomfort to even an adult non-avian dinosaur. Moonspiders hunt at night to avoid becoming prey to diurnal birds and other large hunters.
A particularly nasty tactic developed by moonspiders is to wait near dinosaur nests just as young are hatching. Tuned to pick up the faint scent of egg matter on a night breeze that might indicate the early stages of a hatching, moonspiders are drawn to nests where young are still struggling to free themselves from their shells. In this vulnerable state they are easy prey for the invertebrate.