Scorpions

Characteristics
Scorpions are among the largest arachnids and in Australia some species can obtain a length of around 12 centimetres. They are easily distinguished from other invertebrates by the following features:

   ▪  4 pairs of legs

   ▪  1 pair of palps modified into pincer-like appendages used for grasping and defence

   ▪  Abdomen which tapers into a tail with a sting containing a poison gland. The tail is held over the body in a defensive posture.

The little marbled scorpion, Lychas marmoreus is one of the most commonly encountered species in Australia as it happily lives in many urban environments as well as natural habitats. This species has even been known to wander into houses causing alarm when discovered hiding under everyday household objects. In natural habitats these little scorpions can be found sheltering under the bark of trees, in leaf litter, under rocks or under the bark of fallen logs. This species feeds on small insects, but seems especially fond of termites.

In some parts of the world scorpions are deadly but in Australia they generally give only a very painful sting. Few human deaths have been recorded in Australia resulting from scorpion stings. Using an ultraviolet light source is a good way to locate scorpions in the field as they are nocturnal and fluoresce brightly under such light at night.

Life Cycle
Male and female scorpions perform a mating dance where the male grasps the palps of the female and manoeuvres her over a sperm packet, which he has deposited on the ground. She then takes this up into her reproductive opening. Female scorpions give birth to live young, which resemble small adults. The female will then carry the young around on her back for several weeks before they disperse to fend for themselves. The young will moult several times before they reach maturity.

Feeding
Scorpions are nocturnal predators and feed on a variety of invertebrates. Their prey is usually captured at night among rocks or under the bark of a tree. Scorpions seize prey with their pincers and swing their tail up over the body to strike repeatedly with their sting in the soft, vulnerable parts of the abdomen of their victims. The prey is dead almost instantly and the pincers holding it are used to tear up or sever off small pieces to be passed towards the mouth where the life juices are squeezed out and consumed. Scorpions are known to feed on a variety of insects, spiders, centipedes, millipedes and even other scorpions. Some of the larger species of scorpions may even feed on vertebrates such as small lizards and snakes.

Habitat
Scorpions are found all over Australia and many have become successful inhabitants of deserts. The desert species usually excavate burrows in the ground, often spiralling underground away from the entrance. Other species inhabit more forested environments where they can be found under rocks and logs and also under the bark of trees.

Liocheles waigiensis (common brown scorpion)