Identification of grasshoppers, locusts, crickets and katydids

What do grasshoppers, locusts, crickets and katydids look like?

Size:

• 5 mm - 100 mm in length.

Body:

• Variable from stick-like to bulbous but commonly widest at wing attachment (wide shoulders) with a tapering abdomen.
• Pronotum (segment behind head) draped over sides to form large lateral lobes.
• Body appears hard.

Antennae:

• Thread-like and length is variable (can be longer than body).

Eyes:

• Large, bulbous and well separated.
• Some forms found in caves have very small eyes or none at all.

Mouthparts:

• For chewing or munching and held downward at rest.

Wings:

• One or two pairs if present.
• Forewing hardened, leathery and partially see-through or cloudy.
• Hindwing much larger than forewing, membranous, clear and folds like a fan.
• Both wings have numerous cross-veins forming many cells.
• Wings usually cover the abdomen but short wing species are common in some groups.
• At rest the wings are held tent-like or flat over body, hindwings hidden.

Limbs:

• Six legs that are usually slender with spines.
• Hindlegs specialised for jumping shaped like a chicken drumstick.
• Forelegs of some species (e.g. mole crickets) are spade-like and modified for digging.

Abdomen tip:

• Two short cerci (tails).
• Males have clasping organs while females of some groups have a long prominent spike known as an ovipositor (which is used for laying eggs).

Behaviours of grasshoppers, locusts, crickets and katydids

• They are normally solitary. Some grasshoppers and locusts form foraging swarms while crickets may be found in small groups.
• When disturbed they usually jump, run quickly under cover, or jump into flight usually landing soon after. Some remain still or burrow, while others may have threat displays including, flashing warning colours, or noise-making.
• Most fly in short bursts but some such as the locusts can fly for extended periods. Many usually make slapping, buzzing or whistling sounds as they fly.
• Many grasshoppers and katydids are experts at camouflage. They use behaviour or colouration patterns, and special body forms to help them blend in with their surroundings. For example, some look like twigs, leaves, rocks or bark. In some circumstances they may also look and behave like other insects.
• Some such as mole crickets are strong burrowers.
• Many, especially crickets, are sound producers. To create sound they use special structures along the base of their wings, sides of the abdomen or along their legs. Often these sounds are used to attract potential partners.
• Most are herbivores (plant feeders) and eat a variety of plant materials such as leaves, roots, flowers, pollen, nectar, seeds and fruits. Alternatively some will eat animal and plant debris, lichens and mosses, and a number are predators.
• Crickets and katydids tend to be active at night while grasshoppers and locusts are primarily active during the day.

Where are grasshoppers, locusts, crickets and katydids found?

• In the open, on vegetation, rocks or bare ground.
• Some are cave dwellers.
• Some are found in leaf litter, burrows or live entirely in the soil.
• Some are semi-aquatic and can be seen at the waters edge on aquatic plants or swimming in the water.
• Some live in groups with other insects, for example in ants nests.
• Crickets are often found in sheds and other damp regions around the house.

What looks similar?

• Stick insects can be confused with grasshoppers that look like sticks. Stick insects can be distinguished by their pronotum, which does not drape over the sides to form lobes. They also have tarsi (toes) with five segments and wings that are always shorter than their abdomen.