Despite their striking appearance some Phyllonorycter provide a real identification challenge and in a few cases even checking their genitalia doesn't always lead to a firm answer. Personally I think they're well worth the effort - being able to put a name to these beautiful little creatures is always enormously satisfying. 2020 was a good year for these, as it was for many other members of this family.
White Oak Midget Phyllonorycter harrisella - One in the garden trap on 12th September 2019 and 18 here between 20th May and 15th August 2020. This species occurs here quite sporadically, with 6 in 2016, 2 in 2017 but none in 2015 or 2018 - clearly the 2020 total was exceptional (and included a peak count of 4 on 31st July). Elsewhere 1 at the meadows on 29th April 2019 and one in the adjacent Millenium Wood on 6th May, with a total of 26 found at the meadows between 19th April and 14th August 2020.
White Oak Midget Phyllonorycter harrisella, North Elmham Cathedral Meadows, 29th April 2019
White Oak Midget Phyllonorycter harrisella, North Elmham Cathedral Meadows, 19th April 2020
White Oak Midget Phyllonorycter harrisella, North Elmham, 30th July 2020
Pale Oak Midget Phyllonorycter heegeriella - None. I've not encountered this species for a few years but it must be a reasonable possibility here in North Elmham (although failing to find any in the good Phyllonorycter year of 2020 isn't a good sign - the last time I saw them was in the similarly good Phyllonorycter year of 2014). Fresh heegeriella should be easy enough to separate from fresh harrisella, but worn individuals need more care. Note that the shadow of the antenna (or even the antenna itself) can appear like a dark streak through the forewing base on harrisella so suggesting heegeriella, and (as shown in the last photo above) wear can also create an appearance suggestive of a dark streak. Although heegeriella tends to have more orange near the apex both species seem to vary in this respect. Some of the other average differences (like the curvature of the second dorsal strigula) seem variable and the number and form of costal strigulae isn't clear on worn specimens.
Hornbeam Midget Phyllonorycter tenerella - None. I've never seen this species but now that I've found some Hornbeam at the meadows I shall be looking harder for it.
Scarce Oak Midget Phyllonorycter kuhlweiniella - Singles caught in the garden moth trap on 4 nights between 5th and 15th August 2020 - I've recorded this species at home on just one previous occasion (in 2016). One at the meadows on 31st May 2019 and 8 found there between 25th April and 23rd June 2020. Interestingly this species, and to some extent harrisella and several other species too, seem to be more easily found during the day-time in the early part of their flight period and more easily found coming to light towards the end of their flight period (different generation?).
female Scarce Oak Midget Phyllonorycter kuhlweiniella, North Elmham Cathedral Meadows, 31st May 2019
Scarce Oak Midget Phyllonorycter kuhlweiniella, North Elmham Cathedral Meadows, 25th April 2020
Common Oak Midget Phyllonorycter quercifoliella - Just one in the garden moth trap, on 15th September 2020. This species only occurs sporadically at home (one in 2014 and 3 in 2017). It's easier to find at the meadows where singles on 6th and 22nd May 2019 and 12 between 5th April and 12th September 2020. Also one at Swanton Great Wood on in August 2019. I also found a few mines at the meadows in September 2019.
Common Oak Midget Phyllonorycter quercifoliella, North Elmham Cathedral Meadows, 6th May 2019
leaf-mine of Common Oak Midget Phyllonorycter quercifoliella, North Elmham Cathedral Meadows, 3rd September 2019
Common Oak Midget Phyllonorycter quercifoliella, North Elmham Cathedral Meadows, 5th April 2020
Garden Midget Phyllonorycter messaniella - A total of 12 in my moth trap between 29th July and 25th October 2019, the worst year here since 2015. I had more than that in a single night in 2018 (17 on 13th October). 2020 was an improvement but still fairly average with 20 between 15th June and 14th November. Elsewhere just 3 at the meadows in October 2019 and July and August 2020.
Garden Midget Phyllonorycter messaniella, North Elmham, 15th June 2020
London Midget Phyllonorycter platani - None. I've never seen adults of this species but it seems to be doing well in Norfolk and spreading away from its Norwich stronghold. Having said that, I'm not sure if there is much (any?) London Plane growing in North Elmham, so my chances of finding it here might not be all that great.
Common Thorn Midget Phyllonorycter oxyacanthae - Singles caught in the garden on 10th August 2019, 24th June and 10th August 2020. Previously I'd only identified 2 in 2018. A total of 5 netted at the meadows between 5th April and 13th July 2020, mostly early mornings. Also what I think was one at the meadows on 4th August 2019, but females are a bit harder to confirm with reference to the genitalia and I wasn't 100% sure I could eliminate sorbi, though its size favoured oxyacanthae. Another tricky female was caught at home on 6th August 2020 - the genitalia looked close to this species but I didn't feel confident enough especially as there were external differences compared to most examples of this species (e.g. a complete white line through the centre of the thorax). The genitalia on females are quite delicate and difficult to prepare clearly, so when the differences between species are subtle and the preparation isn't perfect then sometimes you just have to leave them unidentified. Also a leaf-mine at the meadows on 14th October 2019, sharing a leaf with Phyllonorycter corylifoliella.
male Common Thorn Midget Phyllonorycter oxyacanthae, North Elmham, 10th August 2019
leaf-mine of Common Thorn Midget Phyllonorycter oxyacanthae, North Elmham Cathedral Meadows, 14th October 2019
male Common Thorn Midget Phyllonorycter oxyacanthae, North Elmham Cathedral Meadows, 19th April 2020
male Common Thorn Midget Phyllonorycter oxyacanthae, North Elmham Cathedral Meadows, 3rd May 2020
Rowan Midget Phyllonorycter sorbi - One in my garden moth trap on 31st July 2020 was a new species for the garden.
female Rowan Midget Phyllonorycter oxyacanthae, North Elmham, 31st July 2020
Brown Apple Midget Phyllonorycter blancardella - 3 in my garden trap between 19th May and 23rd July 2019 and 4 between 24th June and 14th August 2020. These were my first here, or indeed anywhere, since 2015. An individual on 17th July 2019 showed spines on the tips of the valvae, a genitalic character not normally associated with this species and which initially led to a misidentification as Hornbeam Midget Phyllonorycter tenerella (whose genitalia do have this feature and otherwise look pretty similar to blancardella). The majority of tenerella show an extensively white base to the forewing, so look quite unlike blancardella externally, but there is one photo of a tenerella on Lepiforum that does show a more extensively orange background colour to the forewings, so I figured mine was an example of this form. However when I caught a second individual in 2020 showing the same genitalic feature but looking equally unusual externally for tenerella, my suspicions were really aroused. Surely if I caught 2 tenerella they wouldn't both look so very much unlike the vast majority of online images of tenerella? Eventually I discovered a photo of blancardella genitalia on the Dissection Group that showed these spines on the valvae, highlighting this as a "variant form with spine at end of each valva". More careful examination confirmed that this was indeed the explanation for both moths, the external appearance of which was much more in line with blancardella than tenerella.
male Brown Apple Midget Phyllonorycter blancardella, North Elmham, 19th May 2019
male Brown Apple Midget Phyllonorycter blancardella, North Elmham, 17th July 2019
male Brown Apple Midget Phyllonorycter blancardella, North Elmham, 23rd July 2019
male Brown Apple Midget Phyllonorycter blancardella, North Elmham, 24th June 2020
male Brown Apple Midget Phyllonorycter blancardella, North Elmham, 7th August 2020
Red Apple Midget Phyllonorycter hostis - None. I've never recorded this species although in my early mothing days I caught a female in Bawdeswell which I was advised couldn't be reliably gen detted but looked like this species.
Next page: more Gracillariidae
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