Speckled Home Oak Dot Ectoedemia heringella

Formerly given the vernacular name New Holm-Oak Pigmy. This species colonised the UK in the late 1990s and was first found in Norfolk in 2011, in abundance (see Norfolk Moths).

I first saw this species at Holkham in June 2016 when several were netted flying around Holm Oaks at dusk. As they were shown to me by someone else I didn't manage to get any photos. The following is the first adult I've identified since then, and was identified by examining the genitalia. My understanding (but I'm always willing to be corrected) is that the following in combination only occurs in heringella: 1) signa long, occupying nearly the whole of the corpus bursae, 2) signa wide, 8 reticulations across at the widest point, and 3) comparatively narrow margin to signa (cf. e.g. subbimaculella). The ductus seminalis is also supposed to be narrow but I'm not sure I can make that out. When I examined this I was also examining what I think was Broken-barred Oak Dot Ectoedemia subbimaculella, and the difference in thickness of the margin was striking. It's obviously difficult to measure such tiny distances but I made the margin of the subbimaculella signa somewhere in the region of 8μm and the margin of the heringella signa around 3μm.

female Speckled Holm Oak Dot Ectoedemia heringella showing genitalia (including close-up of part of signum, oriented at 90 degrees to the main genitalia photo), North Elmham (Norfolk, UK), 25th June 2025

I'm not sure where the above insect came from as I don't know of any Holm Oak in the immediate vicinity, but there is a stand of mature Holm Oaks in Elmham Park at the far end of the village. I've also found a single Holm Oak sapling much closer, though that one didn't have any mines on it last time I checked. There may well be others nearer to me. Anyway, the trees in Elmham Park was absolutely heaving with mines. In the photos below the small mines are the heringella ones and the larger thicker ones are Plain Holm Oak Dot Stigmella suberivora.

Speckled Holm Oak Dot Ectoedemia heringella and Plain Holm Oak Dot Stigmella suberivora leaf-mines, Elmham Park, North Elmham (Norfolk, UK), 25th January 2022