Pale Birch Dot Stigmella confusella

Like other members of this family, primarily recorded in its leaf-mine stage. It is reasonably well-recorded across Norfolk but adults are rarely identified. Formerly given the vernacular name Pale Birch Pigmy (one form has a paler forewing).

This one was netted in flight under Rowan so I was hopeful that it would prove to be Barred Rowan Dot Stigmella sorbi, a relatively poorly-recorded species that looks superficially similar. The clean narrow pale fascia didn't look like a good match to photos of that species though and keying it using Kleine Vlinders led to Stigmella confusella or possibly Grey Birch Dot Stigmella lapponica.

Looking at its genitalia quickly ruled out sorbi and confirmed that it was indeed either confusella or lapponica - the oversize central horn of the gnathos is distinctive. I had worked out what the differences in genitalia were between these species when I examined a Stigmella lapponica the year before, and compared to that this one had more uniform sized cornuti in the aedeagus and a wider median notch in the uncus.

male Pale Birch Dot Stigmella confusella showing genitalia (including with separate aedeagus), Beetley Meadows (Norfolk, UK), 27th April 2024