Hanging-fly, line drawing. Hanging-flies and scorpion-flies belong to the insect Order Mecoptera.
- Andrew Howells
- © Australian Museum
What do hanging-flies and scorpion-flies look like?
- Wingspan up to 50 mm across.
- Column-like or widest at wing attachment ('wide shoulders') tapering past this point.
- Head with a beak-like extension.
- Appears soft and fragile.
- Thread-like, with many segments and longer than half their body length.
- Large, bulging and well separated.
- For chewing or munching.
- Located at the tip of beak-like extension of the head.
- Held downwards at rest.
- Two pairs if present (though rarely absent).
- Both pairs are similar in size, membranous, clear, and have numerous cross-veins forming mainly rectangular cells.
- At rest most hold their wings tent-like above their body though some species overlap them.
- Six legs, very long and slender.
- Have large spines at joints.
- Often have large claws for grabbing onto prey and plants.
- Cerci (tails) absent.
- Males have claspers, which are used to hold onto the female during mating.
- In some groups the abdomen is raised similar to the stinging tail of a scorpion hence the common name scorpion-fly.
Where are hanging-flies and scorpion-flies found?
- Usually around moist environments or adjacent to open water. Some however are found in drier habitats.
- On herbs and low shrubs that have many leaves. Occasionally amongst tall grasses or on flower heads.
- One wingless species can be found on snow (Tasmania only).
What do hanging-flies and scorpion-flies do?
- They are solitary.
- When disturbed they fly away, flying only in short bursts.
- They tend to be weak, slow, flapping fliers.
- Hanging-flies hang from plants by their forelegs waiting to catch prey with their hind legs.
- Both hanging-flies and scorpion-flies tend to be predators preying on flies, moths, bees, spiders and various larvae. Some are also scavengers taking nectar as they hunt.
- They are active during the day.
What looks similar?
- Lacewings can have a beak-like extension of the head but it is never as long as you would see in a hanging-fly or a scorpion-fly. Lacewings are distinguished by the forked veins along the margins of their wings.
- Alderflies/dobsonflies are easily distinguished as they lack a beak-like extension of head.
- Crane flies (order Diptera, family Tipulidae) are often confused with hanging-flies as they have long legs and have a habit of hanging on plants. Craneflies can be distinguished by only having one pair of fully functional wings.