The velvet worms (Onychophora — literally "claw bearers") are a minor ecdysozoan phylum with approximately 180 species. These obscurely segmented organisms have tiny eyes, antennae, multiple pairs of legs, and slime glands. They have variously been compared to worms with legs, caterpillars, and slugs. Most common in tropical regions of the Southern Hemisphere, they prey on smaller animals such as insects, which they catch by squirting an adhesive mucus. In modern zoology, they are particularly renowned for their curious mating behaviour and for bearing live young.