Beetles in the Elateridae family are commonly known as click beetles or skip jacks, and the larvae (below) are know as wire worms. There are 9000 species world wide, and 73 species in Britain. The adults range in length from 0.2 cm - 7.0 cm. The fossil record for this family goes back as far as the Jurassic.
The larvae (above and below) are known as wire worms, they live on plant roots and cause a large amount of damage. In the UK DEFRA (2010) have recorded click beetle populations as high as 2.5 x 106per hectare, and 3.8 x 106 per hectare on permanent pasture.
It can take a larva five years of feeding before it is ready to pupate. The larva is elongate and cylindrical, and is usually orange or yellow in colour.
Above and below is the typical Elateridae pupa.
When click beetles are alarmed they will drop to the ground and play dead. Often they land on their backs, and once they feel danger has passed with get back up on their feet with a flick of their body. It is this flick accompanied by a clicking sound that gives them their common name. Some beetles can flick themselves to quite a height, and this has become their method of escaping danger.
The adult beetles have the typical elongated body of the Elateridae, with the pointed rear end and the head almost invisible. They feed on pollen, nectar, flowers or leaves.
Above is Athous haemorrhoidalis, the Red-brown skipjack. The adult is 9 - 16 mm long, and has a brownish-black bulging thorax, and reddish-brown elytra (wing cases). It is most commonly seen in the summer months, especially May - July on flowers in or near hedgerows, field margins, woods, bracken and meadows throughout Europe, in England and Wales, it is less common in Scotland, and found in just a few places in Ireland. The larvae damage plant roots.