Editing Scorpion (section)

===Cephalothorax===

The cephalothorax comprises the [[carapace]], eyes, chelicerae (mouth parts), [[pedipalp]]s (which have [[chelae]], commonly called claws or pincers) and four pairs of [[walking leg]]s. 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, which makes it possible for nocturnal species to use starlight to navigate at night.<ref name="Chakravarthy Sridhara 2016">{{cite book |last1=Chakravarthy |first1=Akshay Kumar |last2=Sridhara |first2=Shakunthala |title=Arthropod Diversity and Conservation in the Tropics and Sub-tropics |url=https://books.google.com/books?id=wLiVDQAAQBAJ&pg=PA60 |year=2016 |publisher=Springer |isbn=978-981-10-1518-2 |page=60 |access-date=11 September 2017 |archive-date=31 May 2021 |archive-url=https://web.archive.org/web/20210531031224/https://books.google.com/books?id=wLiVDQAAQBAJ&pg=PA60 |url-status=live }}</ref> The chelicerae are at the front and underneath the carapace. They are pincer-like and have three segments and sharp "teeth".{{sfn|Polis|1990|pp=16–17}}{{sfn|Stockmann|2015|p=26}} The brain of a scorpion is in the back of the cephalothorax, just above the [[esophagus]].{{sfn|Polis|1990|p=38}} As in other arachnids, the nervous system is highly concentrated in the cephalothorax, but has a long ventral nerve cord with segmented [[ganglia]] which may be a [[Primitive (phylogenetics)|primitive]] trait.{{sfn|Polis|1990|p=342}}

The pedipalp is a segmented, clawed [[appendage]] used for prey immobilization, defense and sensory purposes. The segments of the pedipalp (from closest to the body outward) are coxa, trochanter, femur, 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; these are useful as taxonomic [[phenotypic trait|characters]].{{sfn|Polis|1990|p=12}} Unlike those of some other arachnids, the legs have not been modified for other purposes, though they may occasionally be used for digging, and females may use them to catch emerging young. The legs are covered in [[proprioceptor]]s, [[bristle]]s and sensory [[setae]].{{sfn|Polis|1990|p=20}} Depending on the species, the legs may have spines and spurs.{{sfn|Polis|1990|p=74}}