Phasmids, especially the nochturnal stick insects, usually cling to sticks and branches during the day. they hardly move at all during this time. if anyway disturbs their branch, the 'living sticks' move with it. They themselves remain stiff and motionless.
Phasmids are divided into three different groups:
- Stick insects
- Ghost insects
- Leaf insects
Stick insects, as the name suggests, resemble long, thin sticks. They are commonly just the one colour. There are green stick insects, which are well camoflaged in grass, and brown stick insects that can remain hidden on branches. Many stick insects resemble bark (Lonchodes hosei herberti), lichen (Orxines macklotti) or blades of grass (Ramulus species). However some also possess warning colours, for example the Peruvian fern insect.
Ghost insects are somewhat fatter than than their stick insect cousins. Because of their body structure and colour, they are very well camoflaged amoung thin branches. They often have thorny spines over their whole body. the structure of a ghost insect is not so straight and symetrical as a stick insect, rather is is slightly irregular.
The leaf insect is one of the best masters of disguise when it comes to camoflage. Because of the way they ingeniously imtate the appearence of a leaf, they are practically invisable amoung tree foliage. My friends can hardly ever spot the leaf insects in my terranium, and are then astonished when I point them out. The edges of the leaf insect's body appears as though it has been eaten away at, and the 'bitemarks' look really cool. The males of the species Phyllium celebicum even have two small holes in the last quarter of the abdomen. In order to completely blend into the surroundings, when the leaf insect walks it gently sways its whole body from side to side. It now looks just like a leaf blowing in the wind. Thanks to their perfect camoflage, the leaf insect is also active during the day.
When all efforts at camoflage have been in vain and a predator has caught the insect by the leg, it can the whole leg cast off the whole leg without a problem. It is said that the leg will then grow back again, but I have never observed this myself. With my own insects, any missing legs have never grown back.