Ontonychophora is a taxonomic term used to refer to a phylum of invertebrate animals that are commonly known as velvet worms. The word "ontonychophora" is derived from the Greek words "onko" meaning hook, and "nykhe" meaning nail or claw, and "phora" meaning bearing or carrying, which reflects the characteristic features of these organisms.
Velvet worms are worm-like creatures that possess a long, segmented body covered with a velvety texture. They are typically found in terrestrial habitats, particularly in tropical and subtropical regions around the world. Ontonychophora species can vary in size, ranging from a few millimeters to several centimeters in length.
One notable characteristic of ontonychophorans is the presence of their paired legs or appendages that bear tiny claws, called onychophoran legs. These legs are used for crawling and capturing prey, as well as for defense. They also possess a unique method of capturing their prey by squirting sticky secretions, emitted from glandular structures, onto their victims, effectively immobilizing them.
Ontonychophora is considered a primitive group of animals, displaying a range of characteristics that link them to both arthropods and annelids. Even though they have similar characteristics to those of arthropods (such as exoskeleton and jointed legs), they lack certain key features, including segmented limbs. This classification has placed them in their own separate phylum.
In summary, ontonychophora, or velvet worms, are a phylum of invertebrates characterized by their velvety appearance, segmented body, unique onychophoran legs, and glandular secretions used to capture prey.
