Robson could quote only a single record for this species, that of Sang on 4th April 1874 at Wolsingham in Weardale. Since then a few isolated colonies have been discovered. It is possible that its diurnal habits are, to some extent, responsible for the shortage of information about its distribution. It flies on sunny mornings in late March and April, among the upper branches of birches in long established woods. The larvae are obtained much more easily by beating birch and rowan in June and July. They, too, are somewhat difficult to deal with as they burrow into bark for pupation. TCD has found that the provision of pieces of cork or large bottle corks will be accepted as pupation sites, especially if a slit or slight depression is cut in the cork beforehand. There are two main areas in Durham where it has been noted. The Wolsingham district, particularly around Dryderdale, is the most certain area for it, but various parts of Derwentdale have also yielded sporadic records. It was recorded from Gibside by J. W. H. Harrison in 1923 and from near Winlaton by D. McCutcheon in 1982. [...]