The Great Silver Water Beetle is a very rare large aquatic insect that can mainly be found in the Somerset Levels which is a wetland area.   It can be found in grazing marshes in still ditches and ‘rhynes’.  Rhynes are drainage ditches that help to turn wetland at sea level into useful pasture.  It has its name the ‘Great Silver Water Beetle’ because when it swims, bubbles of air get trapped on its underside and these bubbles look almost ‘silvery’ giving this beetle the appearance that it is a silver colour.

The Great Silver Water Beetle is about five centimetres in length and has a black body with a greenish sheen to it.   It is divided into three body parts: the head, the thorax which is the middle part of the body and the abdomen.  The thorax holds three pairs of black legs and two sets of wings. The hind wings are soft and are used for flying and the front wings are quite hard.  The front wings are called 'elytra' and they cover and protect the soft hind wings when the beetle is not in flight.

Great Silver Water Beetles are good swimmers and divers, but they prefer to spend most of their time crawling on water plants because they mainly feed on decaying water plants. The larvae of these beetles eat water snails, but when they are fully-developed they too turn vegetarian like their parents and only eat decaying water plants.