Chrysoperla lucasina

Supposedly a common green lacewing but one I have found rather difficult to find - and identify. Though I am yet to find one hibernating there are some winter records of this species in Norfolk. Unlike the much commoner Chrysoperla carnea (and rarer Chrysoperla pallida) this species does not turn brown in winter, so any lacewing remaining green into the winter would be especially worth checking carefully.

There are three Chrysoperla species in the UK - see my page for Chrysoperla carnea for details of how to separate these from other genera. Differences between lucasina, carnea and pallida are rather subtle. Some Chrysoperla lucasina have a dark line on the membrane between the upper and lower sections of the basal abdominal segments (but don't confuse this with brown on the upper and lower sections themselves), however lucasina does not show this feature consistently (indeed in my experience it usually doensn't - but I have seen it on a Chrysoperla that I don't believe was lucasina). The other main character is the shape of the wing, but this can be hard to judge and some individuals can be especially hard to call on this character. On lucasina the wing is slightly more pointed with a straighter section next to the point on the top side if you're looking at a live insect at rest. The angle you're looking at the insect at can make a big difference to the wing shape and so it's best to give it a good look from all angles, and bear in mind that photos can be quite misleading (e.g. if the wing is slightly bent then this can make it appear more pointed than it really is, especially in photos where the bend may not be evident). The hairs on the leading edge of the wing are shorter compared to carnea too - this is said to be only useful if you have both species together to compare, but if you have a microscope with a graticule so you can measure the length of the hairs then it may be possible to identify with just a single specimen. I've not measured enough to be sure of the limits of both species, but the hairs along the middle of the costa of the one I caught in 2023 were a little over 0.16mm (160μm), whereas those on the carnea I have measured have generally been over 0.18mm (180μm), sometimes over 0.20mm (200μm).

Most of my experience of this species was from my earlier days recording lacewings, which raises some alarm bells regarding the accuracy of those early identifications - was my inexperience leading me to misidentify some of them? I will exclude some of the older ones just in case, and am now checking all carnea-type lacewings especially carefully in the hope of building up a bit more confidence that about these. In 2023 I only managed to find one individual that I consider to be lucasina. This one did not show any trace of a dark membrane between the abdominal tergites and sternites but the wing shape seemed promising on first look. I didn't find it easy to convince myself about this, but after much study and comparison with carnea I was satisfied it was ok. Supporting this ID, the hairs along the costa were clearly shorter than those on carnea.

female Chrysoperla lucasina showing forewings and close-up of mid costal hairs, North Elmham (Norfolk, UK), 10th September 2023

I caught this one in 2022 and examined it carefully. At the time I was content that the wing shape matched lucasina, though subsequently looking back at the photos I became less convinced. However, it is apparent from the photos that the hairs on the costa are short compared to Chrysoperla carnea, so I think I was right. I have so far been unable to find any references describing the abdomen of lucasina, so this is of limited use at least until I have built up more experience of male lucasina, but on this individual at least the abdomen was very similar to that of carnea. The only probable difference I could detect was that the 'lip' is long, protruding further than it normally does on carnea. In other respects (e.g. height of lip compared to chin, length of hairs on lip, presence of dark hairs) it resembled typical carnea and not pallida.

male Chrysoperla lucasina showing forewings and abdomen tip from side, North Elmham (Norfolk, UK), 29th October 2022

Of my older records I think these two look ok.

Chrysoperla lucasina, North Elmham (Norfolk, UK), 13th October 2017

Chrysoperla lucasina, North Elmham (Norfolk, UK), 16th August 2017