Veetund TääKsis English

Post on 17-May-2015

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Collecting aquatic insects by landing net and watching

They rely on surface tension to walk on top of water.

They can move very quickly, up to 1.5 m/s

(other names: water strider, water scooter)

small moth-like insects having two pairs of hairy membranous wings

The larvae of many species make protective cases of silk decorated with gravel, sand, twigs or other debris (30 mm)

The skin splits at a weak spot behind the head and the adult dragonfly crawls out of its old larval skin, pumps up its wings, and flies off to feed on midges and flies.

Dragonfly nymph ( 50 mm), using extendable jaws to catch other invertebrates

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Spreadwing damselfly Zygoptera) - rest with their wings folded together

Damselfly (Lestidae)hold them at an angle away from their bodies

The male has metallic blue wings, the female has brown wings. (70 mm)

The larva(35 mm) They usually overwinter in mud or slime.

The last pair of the legs are modified for swimming and often bear rows of long hairs to aid this purpose. Larva (“water tiger”)

They collect air under their elytra and are able to breathe this collected air using spiracles hidden under the elytra.

•The eyes are divided allowing them to see both above and below the water surface

•They can also fly

They are easily recognized by the erratic swimming behavior (5 mm)

Adult is short-lived, from a few hours to a few days. The primary function of them is reproduction

The naiad stage may last from several months to as long as several years,5-23 mm

It’s elongated caudal siphon, or breathing tube is the scorpion’s long “tail”

Their fore legs are like jack knives.They have wings, but seldom fly. 

Swim on their back, vigorously paddling with their long, hair-fringed hind legs. They can fly well and so migrate easily to new habitats