Yorkshire Status: Common and widespread resident.

Blair's Shoulder-knot was first found on the Isle of Wight in 1951 and gradually spread north, reaching Yorkshire in 1991 with records that year in VC61, 62 and 64. By the following year it had reached VC63 and by 1999 it had reached VC65. It can now be found as far north as central Scotland. Numbers increased rapidly and peaked around 2005, followed by a plateau and a gradual fall-off since then. Rapid growth is often seen with species moving into the county in this fashion. Sooner or later its parasitoids catch up with it and do a better job in controlling its numbers.

This species feeds on alien conifers, in particular Leyland, Lawson's and Monterey cypress. It is therefore a common garden moth in those gardens with leylandii hedges. It is a much rarer moth away from these habitats. The largest catch was 37 at Burley-in-Wharfedale on 10/11/2005 in the early part of its colonisation. It is usually an easy moth to identify though we have seen it confused with Sprawler. Unlike several other members of the genus, it just flies in Autumn and does not over-winter as an adult.

Recorded in 121 (61%) of 200 10k Squares.
First Recorded in 1991.
Last Recorded in 2024.
Additional Stats