Chrysoperla pallida

This species was split from the extremely similar Chrysoperla carnea after the publication of Plant's key. See Henry, Brooks, Duelli and Johnson (2002)¹ for details. I am not aware of any confirmed records of this species in the UK north of Essex prior to 2022 but there were a couple of credible but unconfirmed reports in west Norfolk in 2016. The same observer caught another in 2022 and this time retained the specimen which does indeed appear to be pallida. With three records in 2026 it may be that this is a recent colonist and increasing in the county.

After examining the abdomens of over 400 male Chrysoperla carnea in the hope of finding a pallida, I finally found what seems to fit pallida in 2023. The shape of the abdomen on live Chrysoperla can appear to change slightly, so that an individual that appears to be ambiguous on initial examination can be more obviously carnea on a subsequent examination. Occasionally I've even caught individuals that looked like they might be good contenders for pallida at first, but when I've looked at them a second time they've been carnea. The one below looked very promising on first examination, and continued to do so each time I re-examined it. Not only was the shape right, but it was also very striking to see how the lip lacked any long hairs at all, quite different from any of the 400 male carnea I have examined. Clearing the abdomen in potassium hydroxide can help to see the shape more clearly, and after doing this I remained happy that the shape matched pallida. I was unable to detect any differences in the internal structures compared to carnea. Viewed from above and below, the end of the abdomen appeared to be slightly flatter compared to a carnea I was examining at the same time - even slightly notched from above. However, I have not checked many carnea from these angles so I'm not sure if that is relevant to the ID or not - something to investigate in future perhaps.

On the majority of carnea, some of the long hairs on the lip (as well as elsewhere on the abdomen tip) are dark, but this is not always the case - some can have entirely pale hairs on the lip. The lip hairs are normally pale on pallida, but it is not safe to identify pallida based on this character as it can be matched by carnea. It has been suggested that pale hairs on the underside of the abdomen might be a useful character for pallida too, but I think this is quite common on carnea too (it's also typical on lucasina which has an abdomen structure similar to carnea).

It's also been suggested that a narrow dark bar in front of the eye may be useful for identifying pallida. If so then it's not simply the presence or absence of the bar as carnea also has, to a lesser or greater extent, a dark bar here. I examined this character on a series of over 20 carnea recently and there was quite a bit of variation. None were precisely the same shape as on this pallida, so there may be something in this, but if so I think it needs more work to define exactly what we should be looking for.

¹ Henry, Brooks, Duelli and Johnson (2002). Discovering the True Chrysoperla carnea (Insecta: Neuroptera: Chrysopidae) Using Song Analysis, Morphology, and Ecology by Henry, Brooks, Duelli and Johnson in Ann. Entomol. Soc. Am. 95(2): 172-191 (2002) (can be downloaded here).

male Chrysoperla pallida showing forewings, close-up of mid costa, face, abdomen tip from side (before and after clearing), abdomen tip from below (cleared) and abdomen tip from above (cleared), North Elmham (Norfolk, UK), 10th October 2023

This one showed a large chin but the lip wasn't as small as the last one, so I wasn't immediately convinced that it was another pallida. However on closer inspection it became clear that the lip lacked the long hairs of the surrounding plates - just a downy covering of very short hairs. This is quite difficult to capture in 2D photos because surrouding hairs can appear as if they are coming from the lip but under the microscope I could see that this wasn't the case.

The shape of the chin and the short hairs on the lip helped rule out carnea but as this was a relatively green individual it's worth noting that lucasina was also eliminated on the length of the hairs along the costa - these were comfortably as long as on carnea and much longer than on any lucasina I've examined.

male Chrysoperla pallida showing abdomen tip from side (3 views) and forewings, North Elmham (Norfolk, UK), 8th February 2026

I picked this one out as a candidate for pallida on account of the large chin. The pale hairs on the lip and chin, and the lack of long dark hairs on the lip seemed to support this, but when I looked more closely there were a few longer hairs on the lip. Pale, half as long as they usually are on carnea and very sparse, but undeniably there were longish hairs on the lip. The diagrams in Henry et al. show only the extremely short dense hairs on the lip and chin that are present on both species, but absolutely no longer hairs on the lip on pallida, so I started to think it must be an unusual carnea. However, after catching another similar individual later in the month (scroll down for that one) and comparing it side-by-side with carnea, I am struggling to see how they can be carnea. My working assumption is therefore that these are pallida and thus that pallida can show longer hairs on the lip, but in that case they are pale, sparse and relatively short (roughly half the length they are on carnea).

Note that in one or two of the photos the hairs on the lip look dark, but they were clearly pale when viewed through the microscope. Backlighting has made them appear darker in some photos.

male Chrysoperla pallida showing head (3 views), forwing hairs (mid costa, both wings) and abdomen tip (3 views), North Elmham (Norfolk, UK), 4th September 2026

This appeared to have a deep chin when viewed with a hand lens, and the lip was so small it disappeared if it wasn't perfectly side-on. In the photos the chin merges isn't very distinct, curving gently into the underside of the abdomen.

I don't find it easy to photograph the abdomen in a way that clearly shows the hairs, so I've included several takes. As above, where the hairs on the lip or chin appear dark this is a trick of the light - they were clearly pale. In the last few photos I have placed the abdomen next to a male Chrysoperla carnea (from Kent on 18th September) to show the difference in both shape and especially in the hairs. Some carnea may show pale hairs, but the combination of relatively short sparse pale hairs together with the deeper chin relative to the depth of the lip should, I think, secure the ID as pallida (at least assuming other species including lucasina have already been eliminated). The long hairs on the chin are also shorter than they are (at least usually are) in carnea (and pale, but they can be pale in carnea too).

male Chrysoperla pallida showing head (2 views), forewing, forwing hairs, abdomen from sideand abdomen tip (2 views), North Elmham (Norfolk, UK), 27th September 2026

Here is the last individual side-by-side with a male carnea.

aabdomens (4 views) of male Chrysoperla pallida, North Elmham (Norfolk, UK), 27th September 2026 (left) and male Chrysoperla carnea, Cooper Street, near Ash (Kent, UK), 18th September 2026 (right)