What do stoneflies look like?

What do stoneflies look like?

Size:

• 4 mm - 60 mm in length.
• Wingspan 10 mm - 110 mm.

Body:

• Column-like and often flattened.
• Appears soft and fragile.

Antennae:

• Thread-like, with many segments.
• Often longer than half body length.

Eyes:

• Bulging and well separated.
  

Mouthparts:

• For chewing or munching.
• Held in front at rest.

Wings:

• Two pairs if present.
• Both pairs membranous and clear.
• Most species have moderate number of wing cross-veins that form long rectangular cells.
• Few species have numerous cross-veins and cells.
• Hindwings are shorter and wider than the forewings.
• At rest, wings overlap and are held flat over body or often curving around the abdomen.
• Generally cover the abdomen though a few species have short wings.

Limbs:

• Six short legs.
• Fore- and midlegs held out from body and bent at 'elbows'.

Abdomen tip:

• Two moderately long cerci (tails) with many segments.

Where are stoneflies found?

• Close to creeks or rivers generally on adjacent vegetation, or behind bark and logs.

What do stoneflies do?

• They are solitary.
• When disturbed they are reluctant to fly: often running quickly to cover, raising wings to appear larger or flying away to land again soon after.
• They are weak flapping fliers, only flying in short bursts.
• Most use colours and patterning to blend in with their surroundings. Though some large alpine species have brightly coloured wings.
• They feed on plant debris, algae, lichen, rotting wood and bark.
• They are active during either the day or night; night active species are attracted to lights.

What looks similar?

• Alderflies or dobsonflies can look a lot like stoneflies. However they can be distinguished by the fact most hold their wings tent-like, they do not have cerci (tails), and they hold their legs underneath their body.