Cochylis nana, a Tortrix Moth
Cochylis nana is a beautiful Tortrix Moth, but like so many other Tortrixes there is no vernacular name for it. It is quite a colourful chap. The ground colour is a greyish white covered in ochreous, brownish and blackish markings. The legs are greyish white as well and ringed. It is not a very difficult species to identify. Cochylis nana is small, even considering it is a Tortrix Moth, for the wingspan is only some 12 to 15 mm.
The eggs are deposited on the catkins of birch. The caterpillars live on and in the catkin, which they eat. By the time the catkins will fall off the tree they move to the trunk of the tree looking for a crevice. Once inside they spin a cocon in which they hibernate being a full grown larva. In spring they pupate inside the same cocoon. The adult moths then fly from mid May to mid July. This species only lives on birch catkins.
Cochylis nana only flies by night. It can be attracted by light though. This is quite a local species throughout the British Isles, appearing in very small numbers only. A local and never numerous species all over Europe, Northern Asia, Japan and Northern America.