of the Best beetles

Here we showcase some of Somerset’s amazing beetle species.

Cockchafer 

Melolontha melolontha

The cockchafer or maybug is a familiar beetle in springtime, often attracted to lights and flying clumsily during its disorientation. When digging in your garden or pots you may find the thick, creamy-white c-shaped larvae (which may also be from the rose chafer).

It is the UK’s largest scarab beetle, a group that includes dung beetles.

Size: 20-30mm.

Habitat: Woodlands, gardens and meadows. When: May or June

Lifecycle lasts about three years, but adults only last up to two months in their final year. Larvae are often found in the soil throughout the year.

Diet: Adults feed on leaves and larvae feed on roots of grasses and crops. Features: The tips of the male beetles’ antennae are made of a series of club-shaped structures that form a fan-shape, ideal for sensing the smelly pheromones given off by female cockchafers. Female cockchafers have relatively simple, club-shaped antennae.

Status: Once an extremely common beetle in Somerset, their numbers are much reduced due to targeted and widespread use of pesticides.

Benefits: Provide food for large bats such as noctules and greater horseshoes, little and tawny owls, foxes, badgers, moles and corvids such as rooks (an old name for the larvae is rookworm).

Violet oil beetle

Meloe violaceus

Bulky beetles with bulbous abdomens, large flat heads and a metallic sheen due to reflective structures in their outer skeleton. In Somerset you are most likely to see the violet oil beetle (We also have Black oil beetles and Rugged oil beetles).

Size: Up to 3cm (females larger than males).

Habitat: Woodland edge habitats, glades and rides, upland moorlands and on flower-rich grasslands. When: March, peaking in April/May. Adults and juveniles (triungulins) emerge at the same time in spring unlike other oil beetles whose triungulins all emerge in summer.

Diet: Adults feed on lesser celandines that flower in early spring and soft grasses.

Lesser stag beetle

Dorcus parallelipipedus

Features: The juveniles are louse-like and climb flowers to hitch a ride on visiting early flying solitary mining bees (hence early emergence), feeding on their pollen and nectar when they arrive at the nest. Oil beetles get their name from a toxic, oily substance that they produce from their leg joints; it helps deters predators when attacked. Status: The south west of England remains a stronghold for violet oil beetles. Once widespread across the UK, they are now rare in eastern parts of England due to the loss of wildflower meadows and species-rich woodland edges. Benefit: Presence of oil beetles is a good sign of healthy mining bee populations.

The lesser stag beetle is a robust, large beetle with large jaws to suit. It is not as large as the greater stag beetle found in the south east of England.

Size: Up to 3cm.

Habitat: Woodland, traditional orchards, parkland and hedgerows. When: May to September.

Diet: The larvae or grubs feed on rotting dead wood (above ground) such as fallen trees and stumps, particularly ash, beech and fruit trees such as apple and plum.

Features: Life cycle two to three years.

Status: Common.

Benefit: Help dead wood to rot down into the soil. Important food for woodpeckers, badgers, hedgehogs, foxes and larger birds such jays.

Great silver diving beetle Hydrophilus piceus

Though strong fliers over large distances, diving beetles are adept at living underwater, trapping air bubbles between their wing cases and body. There are many species of diving beetle, but one of the largest and rarest is the great silver diving beetle. Adults can make a ‘squeak’ if handled.

Size: Up to 5cm.

Habitat: Slow-moving interconnecting waterways such as rhynes, lakes, overgrown ponds, ditches, wet woodlands and marshy areas. When: Found throughout the year and can live up to three years. Mostly seen from April to June when females are actively seeking egg laying sites.

Diet: Adults mostly feed on decaying underwater plants and will predate other animals. The larvae have sharp jaws and eat small aquatic animals such as tadpoles, dragonfly larvae, small fish and freshwater snails. Smaller species of diving beetles eat mosquito larvae.

Features: Females lay up to 60 eggs in a cocoon which is left amongst waterside plants or floating on the water. Hairs on the insects body trap air, allowing the beetle to breathe underwater. This air pocket shimmers underwater, giving them part of their name 'silver'.

Status: Rare. The Somerset Levels are a real hotspot. Also found in the far south east of England and the coastal marshes of East Anglia. Benefit: The predatory larvae help keep populations of smaller invertebrates in check. Adults and larvae provide food for waterbirds such as little grebes.

Violet ground beetle

Carabus violaceus

Violet ground beetles are active predators (both adult and larvae), coming out at night to hunt. Their elytra have a beautiful, metallic sheen.

Size: Up to 3cm.

Habitat: Gardens, woodlands, farmland and meadows. Most often found under stones, logs or leaf litter.

When: March to October

Diet: Slugs, snails, worms and insects. Features: Oval-shaped black

Glow worm Lampyris noctiluca

The glow worm is in fact a beetle and not a worm, and often found as larvae, especially when they are crossing pathways looking for food. Males look like a typical beetle while females look like a lava (and not dissimilar to a ladybird larva). Thanks to a chemical called luciferin, females (and larvae) are bioluminescent and can be found glowing at dusk.

Size: Up to 2.5cm.

Habitat: Grasses and low vegetation in open woodlands, gardens, hedgerows, railway embankments, heathlands, cliffs, often along paths, rides and tracks.

When: May to September, peak June to July.

Diet: Larvae feed on slugs and snails; adults don’t feed.

Features: Glow worm larvae find their food by the chemicals in snail slime. Females give off a yellow-green glow at night to attract males. Once mated, the females stop glowing, lay their eggs and die.

Status: May be locally common; declining although still widespread in Somerset except on the Somerset Levels and East Mendip. Glow worms do not travel more than a few metres, so fragmentation or disappearance of their habitat can mean the species goes locally extinct. Light pollution is also a threat as it can drown out the pale glow of the females and make it harder for males to find them.

Benefit: The presence of glow worms is an important indication of a healthy, well connected environment. They keep populations of snails in check.

beetles with a metallic-purple sheen around the flattened edges of its wing cases.

Status: Common.

Benefit: Their presence is a good sign of healthy populations of smaller invertebrates. Adults may be snapped up by foxes, badgers and hedgehogs while frogs and toads may eat the larvae. Helpful to gardeners as they can help control pest species such as slugs.

Bloody-nosed beetle Timarcha tenebricosa

The bloody-nosed beetle is a large, round, flightless beetle with long legs that can often be seen plodding across paths or through grass. Its common name derives from its unusual defence mechanism: when threatened, it secretes a distasteful blood-red liquid from its mouth.

Size: 14-18mm.

Habitat: Grassland, heathland, hedgerows, broadleaved woodlands where there are openings and clearings.

When: April to September. Although mostly active at night they can often be found during the day.

Diet: One of our largest ‘leaf beetles’, adults feed on the leaves of lady’s bedstraw, hedge bedstraw and related plants, and the dark green, wrinkled larvae can be seen clinging to these species.

Features: A domed, black beetle with a bluish sheen and massive feet. The line running down its back gives the impression of separate wing cases; these are actually fused together and this slow-moving beetle does not fly.

Status: Common in the south west and Wales. Less common in the east of the UK and rare in the north.

Benefit: Larvae may be eaten by birds. The beetles keep their foodplants, such as bedstraws in check.

Green tiger beetle

Cicindela campestris

The sun-loving green tiger beetle is a fast, agile hunter, running across the ground to catch its invertebrate prey

Size: 1 – 1.5cm.

Habitat: Warmth-loving and therefore sunny areas on heathland, moorland, sandy grassland, quarries, woodland rides and sand dunes.

When: April to September.

Diet: Invertebrates including spiders, caterpillars and ants.

Features: A solitary, large, metallicgreen beetle, with purple-bronze legs and eyes, and large, creamy spots on the wing cases. It has a ferocious set of jaws and long legs that give it an impressive running speed. It is one of our fastest insects.

Larvae dig burrows and use them like a pitfall trap, waiting for passing invertebrates and drag them into their burrow. They have a spine on their back that stops them being pulled out of the burrow and helps brace them whilst pulling large prey in.

Status: Common.

Benefit: Being top predator, green tiger beetles indicate plenty of prey species in their environment.

More To Spot

Common sexton beetle

Nicrophorus vespilloides

Sexton beetles – also known as burying beetles - are striking black and orange burying beetles, often covered in tiny mites. These beetles are the undertakers of the animal world, burying dead and decaying animals, such as mice and small birds, in which they lay their eggs. A pair will tend to their young which feed on the decaying animal.

Dung beetles

There are 60 species of dung beetle in the UK helping to recycle dung back into the soil. In woodlands the dor beetle is often encountered between March and October, burying the dung of deer, foxes and badgers in which they lay their eggs. In September on grasslands and heathlands, you may also find the less common minotaur beetle Typhaeus typhoeus, an impressively armoured beetle superbly adapted for dragging dung – often rabbit droppings – back to its burrow. It is named for the male’s three bulllike horns which are used to protect its young and dung.

SOMERSET’S RARER BEETLES:

Hairy click beetle

Synaptus filiformis

This is extremely rare, recorded between Langport and Bridgwater on the River Parrett. This was thought to be the only population in the UK. However, it has been rediscovered in Wales and in Cumbria.

Dune tiger beetle

Cicindela maritima

Very rare; found on the coast between Bridgwater and Weston-super-Mare.

Critically important to protect coastal habitats, especially dunes (such as at Berrow), for insects such as the dune tiger beetle and dune-adapted plants.