Editing Ecdysis (section)

==Spiders==
[[File:Crab spider female in ecdysis; Genus Synema, Family Thomisidae 5725s.jpg|left|thumb|Female [[crab spider]] ''[[Synema decens]]'', teneral after final ecdysis, still dangling from drop line, about to be mated, [[opisthosoma]] still shrunken]]
[[File:Araignée en train de muer.webm|left|thumb|Complete process of a spider moulting.]]

Spiders generally change their skin for the first time while still inside the egg sac, and the spiderling that emerges broadly resembles the adult. The number of moults varies, both between species and sexes, but generally will be between five times and nine times before the spider reaches maturity. Not surprisingly, since males are generally smaller than females, the males of many species mature faster and do not undergo ecdysis as many times as the females before maturing.
Members of the [[Mygalomorphae]] are very long-lived, sometimes 20 years or more; they moult annually even after they mature.

Spiders stop feeding at some time before moulting, usually for several days. The physiological processes of releasing the old exoskeleton from the tissues beneath typically cause various colour changes, such as darkening. If the old exoskeleton is not too thick it may be possible to see new structures, such as [[seta]]e, from the outside. However, contact between the nerves and the old exoskeleton is maintained until a very late stage in the process.

The new, teneral exoskeleton has to accommodate a larger frame than the previous [[instar]], while the spider has had to fit into the previous exoskeleton until it has been shed. This means the spider does not fill out the new exoskeleton completely, so it commonly appears somewhat wrinkled.

Most species of spiders hang from silk during the entire process, either dangling from a drop line, or fastening their claws into webbed fibres attached to a suitable base. The discarded, dried exoskeleton typically remains hanging where it was abandoned once the spider has left.

To open the old exoskeleton, the spider generally contracts its abdomen ([[opisthosoma]]) to supply enough fluid to pump into the [[Cephalothorax|prosoma]] with sufficient pressure to crack it open along its lines of weakness. The [[carapace]] lifts off from the front, like a helmet, as its surrounding skin ruptures, but it remains attached at the back. Now the spider works its limbs free and typically winds up dangling by a new thread of silk attached to its own exuviae, which in turn hang from the original silk attachment.

At this point the spider is a callow; it is teneral and vulnerable. As it dangles, its exoskeleton hardens and takes shape. The process may take minutes in small spiders, or some hours in the larger Mygalomorphs. Some spiders, such as some ''[[Synema (spider)|Synema]]'' species, members of the [[Thomisidae]] (crab spiders), mate while the female is still callow, during which time she is unable to eat the male.<ref>{{cite book |author=Erik Holm & Anna Sophia Dippenaar-Schoeman |title=Goggo Guide: the Arthropods of Southern Africa |publisher=LAPA |year=2010 |isbn=978-0-7993-4689-3}}</ref>