<P> The eurypterids, commonly called "sea scorpions", were marine creatures that lived during the Palaeozoic era that share several physical traits with scorpions and may be closely related to them . Various species of Eurypterida could grow to be anywhere from 10 centimetres (3.9 in) to 2.5 metres (8.2 ft) in length . However, they exhibit anatomical differences marking them off as a group distinct from their Carboniferous and Recent relatives . Despite this, they are commonly referred to as "sea scorpions". Their legs are thought to have been short, thick, tapering and to have ended in a single strong claw; it appears that they were well - adapted for maintaining a secure hold upon rocks or seaweed against the wash of waves, like the legs of a shore crab . Cladistic analyses have supported the idea that the eurypterids are a distinct group from the scorpions . </P> <P> The body of a scorpion is divided into two parts (tagmata): the head (cephalothorax) and the abdomen (opisthosoma), which is subdivided into a broad anterior (mesosoma), or preabdomen, and a narrow tail - like posterior (metasoma), or postabdomen . </P> <P> The cephalothorax, also called the prosoma, comprises the carapace, eyes, chelicerae (mouth parts), pedipalps (the pedipalps of scorpions have chelae, commonly called claws or pincers) and four pairs of walking legs . The scorpion's exoskeleton is thick and durable, providing good protection from predators . Scorpions have two eyes on the top of the cephalothorax, and usually two to five pairs of eyes along the front corners of the cephalothorax . While unable to form sharp images, their central eyes are amongst the most light sensitive in the animal kingdom, especially in dim light, and makes it possible for nocturnal species to use star light to navigate at night . Some species also have light receptions in their tail . The position of the eyes on the cephalothorax depends in part on the hardness or softness of the soil upon which they spend their lives . </P> <P> The pedipalp is a segmented, chelate (clawed) appendage used for prey immobilization, defense and sensory purposes . The segments of the pedipalp (from closest to the body outwards) are coxa, trochanter, femur (humerus), patella, tibia (including the fixed claw and the manus) and tarsus (moveable claw). A scorpion has darkened or granular raised linear ridges, called "keels" or carinae on the pedipalp segments and on other parts of the body, which are useful taxonomically . </P>

Are the claws on the scorpion considered to be walking legs