Coniopteryx lentiae

One caught in my garden in 2019 was the first record for Norfolk. By 2021 I had caught 6 - 4 here and 2 at the nearby Cathedral Meadows (half were in my moth trap and the other half were netted in flight). I haven't seen the hard data to confirm this but I get the impression that this species is increasing its range northwards and is probably therefore a recent colonist to Norfolk. Presumably it is now reasonably common elsewhere in Norfolk too, but with hardly anyone else recording waxflies currently this is yet to be confirmed.

Coniopteryx species are separated from Conwentzia by the size of the hindwing and from other waxfly genera (Semidalis in Norfolk) from details of wing venation. Only male Coniopteryx can be identified to species level - esbenpeterseni and lentiae differ from the other species in the genus in having their genital structures arranged in a ring. That ring is larger and looser in lentiae compared to esbenpeterseni, about the same height as the height of the hypandrium (the darkened structure beneath it, at the apex of the lower part of the abdomen). The parameres are also attached to the bottom of the ring, not the side as on esbenpeterseni. Some care is required when checking for these features - the ring is rather delicate and can easily be tightened slightly when clearing it, making it appear smaller and shifting the position of the parameres to nearer the side. The characters are usually visible after the abdomen has been macerated in 10% potassium hydroxide, and even though you may wish to clean it further for a clearer view of the structures, I recommend ensuring you have seen (and preferably photographed) it well enough to name it before applying any pressure to it in order to clean it further.

On this individual you can see the large genital ring with the paramere attached to the bottom and the similar-sized hypandrium below:

male Coniopteryx lentiae, North Elmham Cathedral Meadows (Norfolk, UK), 6th July 2020

Here I placed the genitalia next to a Coniopteryx esbenpeterseni I caught 3 days earlier, so you can see the differences more clearly. The esbenpeterseni (on the left) has a much smaller, tighter genital ring much smaller than the hypandrium beneath it. The paramere extending back from the ring emerges from the side of the ring, not the bottom.

male Coniopteryx lentiae, North Elmham (Norfolk, UK), 26th June 2019 - showing genitalia with those of a Coniopteryx esbenpeterseni from the same location on 23rd June.

Even though I didn't do a very good job of clearing the abdomen for this one, you can still easily see the large genital ring with the paramere attached to the bottom and the similar-sized hypandrium below:

male Coniopteryx lentiae, North Elmham (Norfolk, UK), 13th August 2020

Here I did an even worse job but you can still just about make out the large genital ring and you can see that the paramere is attached to the bottom of it:

male Coniopteryx lentiae, North Elmham (Norfolk, UK), 22nd June 2020

male Coniopteryx lentiae, North Elmham (Norfolk, UK), 26th June 2021

male Coniopteryx lentiae, North Elmham Cathedral Meadows (Norfolk, UK), 8th June 2020