Britain's largest terrestrial insect is the stag beetle while our biggest flying insect is the magnificent emperor dragonfly, boasting a wingspan of four inches.

Males have an apple green thorax and sky blue abdomen while females are mainly light green with a few brown markings.

The photo shows an emperor, which we should perhaps call an empress laying eggs into a water plant below the surface.

The odd thing about the photo is that perched on a wing of the empress is a blue damselfly which clearly illustrates the difference in size between the two species.

When the larvae or nymphs hatch they spend two years slowly growing, changing their skins several times.

They are voracious predators, feeding on tadpoles, small fish and invertebrates, stalking their prey and when close, shoot out their extendable lower lips which snatch their victims to be eaten at leisure.

If the nymph is threatened it spurts out a jet of water from its rear end to move away. Rocket science indeed!

The adult emperor can fly forwards, backwards, up down and hover. Its all round vision can spot prey in any direction and it will zoom up to intercept.

The emperor's bristly forward pointing legs form a sort of basket, rather like an aerial fishing net with which it catches flying insects as large as meadow brown butterflies or can dash into a garden spider's web and extract the spider from the centre.