 If you look into the water of virtually any stillwater you will notice the small beetle-like creatures forever rising to the top only shoot back to the bottom in the wink of an eye. These are not beetles but the Corixa. They are abundant in most stillwater from the smallest pond to the largest lakes and reservoirs, they are an important food source for the trout and must not be ignored by the angler.
At close range the Corixa is a striking creature, its back is beautifully marked with dark brown or black dashes with bands of gold. It’s air supply (a small bubble on the underside of its abdomen) when at full capacity looks like a bead of mercury held between the legs. There are quite a few different species of Corixa, but their colour and markings are very similar, so we do not need to go to great lengths to imitate all the species. They do vary a little in size ranging from about 5mm to over 10mm, though the larger species tend to be less abundant. The most common and one usually imitated is about 7mm. | 
