This Corixa imitates various species of natural corixidae, these are very common in all types of water and I think this pattern is a good representation of them, and although they are a staple diet of trout at certain times of the year, they are often only taken when other more succulent forms of food are in short supply. This is not a new artificial. Leonard West recommended a dressing to represent them in the early part of this century, although it should be pointed out this was intended to be fished in running water. The earliest record I can trace of a dressing intended specifically for stillwater is a pattern perfected by C.E.Walker and detailed in his book Old Flies in New Dresses. Since then many dressings have appeared and the one I have chosen is I hope representative of most of them. It can be dressed as a weighted or unweighted pattern. On most reservoirs and lakes the best time of the year to fish this artificial is from mid-July to mid-September.
During the day I have found the weighted pattern to be more effective fished on the point with a floating line and retrieved by the sink and draw method. In the very early morning or late evening there is no doubt that the unweighted pattern is more killing, for when the light is poor the trout become bolder and chase the corixa into very shallow water. At this time the artificial should be retrieved fairly fast just under the surface. A good compromise which sometimes seems to be effective is to fish the weighted version on the point with the unweighted one on a dropper.
If a weighted pattern is required, copper wire or strip lead should be wound around the shank of the hook. Then proceed in the following manner for both patterns.With brown tying silk tie in at the bend a bunch of brown squirrel tail fibres, followed by a length of fine silver wire, and white floss. The floss is then wound down to the eye, full in the center to give a well tapered body. This is then ribbed with the wire, and the squirrel fibres are stretched over the top of the body to form the wing cases and whipped in at the eye. Finally six fibres from a grouse hackle are tied in under the eye, sloping well back under the body. To prolong the life of the very fine squirrel tail fibres, it is a good idea to apply a dab of varnish at each end.
Hooks: Size 10 to 12.
Rib: Fine Silver Wire.
Body: White silk floss.
Throat Hackle: Six fibres from a Grouse hackle.
Wing Cases: Bunch of Squirrel tail fibres.