class cyclostomata are without jaws
there eg are :
petromyzon
myxine
Chelicerates (crabs, Pycnogonida, and Mercostonata) are arthropods that lack jaws.
chelicerates
chelicerates
The mandibles of arthropods open side to side. The jaws of humans open up and down.
Chelicerates are a group of arthropods that lack jaws. Examples of chelicerates include horseshoe crabs, mites, ticks, spiders, and scorpions. Arthropods that have jaws are classified as mandibulates.
Mandibles are jaws and are used for eating.
Well, actually, arthropods don't have jaws, but I know what you mean. Arthropods have mandibles. Mandibles open side to side, which is great for slicing and tearing!
Lampreys
Crustaceans have exoskeletons, two pairs of antennae, two pairs of maxillae, biramous legs, and mandibles, which are like jaws.
Myxini, the hagfishesLampreys are as well, but their class has not been determined.
They express the characteristics inherent to arthropods. All insects are arthropods. Not all arthropods are insects.
Hagfish. Hagfish are primitive marine animals that belong to the class Myxini. They are known for their lack of jaws and paired fins.