ON THE WILD SIDE Sensitive fly is a real hard case
WALK in the woods around this time and you’ll smell the ramsons, or “wild garlic”.
As well as having pretty white flowers, it cooks up into a decent bowl of soup.
Caddisflies, also known as sedgeflies or railflies, are a huge family of little insects that love our freshwaters.
Many fishing “flies” are designed to look like them to attract a catch.
The Latin name of the caddisfly means “hairy wing”, and it is a good descriptor as many species have four pairs of very hairy wings. Otherwise they are quite like their moth cousins but with two long antennae.
They are moth-like in more than their appearance, as they are nocturnal and attracted to light.
There are around
200 UK species of caddisfly, making them one of our more common water-dwellers.
Adults in the biggest species are only about
3cm long. They have very small, very weak mouths and rarely eat anything, so they don’t live very long.
All but one species lay their eggs in water – that one being an endangered species which only has babies under wet leaves in the West Midlands.
These little water beasts are very small and delicious and very easy to be taken by predators. Or they would be if they didn’t have one very special adaptation – silk glands on their mouths. Most caddisfly larvae use them to stick things together to make tubes to live in and walk around in, with the protective tubes hiding most of their body, like a mouse in an empty toilet roll.
These tubes, inset, can be made of just about anything and different species use different things, such as the mottled sedge which only uses tiny pieces of flat leaves.
Cases of wood, rocks, sand, plants and even broken snail shells have all been recorded as being used. One French artist even had caddisfly larvae make their cases out of tiny fragments of real gold and jewels.
The oldest fossilised adult caddisfly dates back about 230million years, but the more durable cases have been found dating back a further 50million. Caddisflies are very sensitive, so are one of the first things to go when water is polluted. They are an important little bug for researchers in this way as they are very easily
studied.