Neureclipsis bimaculata - One caught in the garden on 16th July 2019 was my first ever of this species, which can be reasonably distinctive when fresh. None in 2020.
female Neureclipsis bimaculata, North Elmham, 16th July 2019
Holocentropus picicornis - One at the meadows on 22nd August 2019 but none at home that year. This is one of the species where in 2020 I really missed the trichoptera.insects-online.de website that had images of most of our caddisfly abdomens. I caught 4 female Holocentropus caddisflies in the garden moth trap in 2020, 3 on 31st July and one on 10th August.
As far as I remember I didn't struggle with the ID too much in 2019 and before, when I was able to compare with the trichoptera.insects-online.de website, but in 2020 I've really struggled using just the Barnard and Ross handbook. I wish I'd taken photos of the genitalia before! At the moment I'm not 100% sure what the 2020 records were but I've reached a conclusion that seems to make sense. I've only ever recorded picicornis before but both Holocentropus dubius and Holocentropus stagnalis occur in Norfolk (if not necessarily in the Wensum Valley) so they need to be ruled out (incidentally the wing venation was checked carefully to ensure that they were all Holocentropus).
The diagram in Barnard and Ross show the ventral appendages much further apart in picicornis than in the other two species (especially compared to dubius where they are shown much closer together), but it doesn't highlight this as a relevant ID feature so I'm not sure it necessarily is. In that respect though, all four of mine were unlike the diagram for picicornis, and closest to dubia. There should be two pairs of ventral appendages in dubia which sounds like it should be easy to sort out, and when I looked at the first one there was a pair of similar shapes behind the top ventral appendages which I thought might be that second pair of appendages (see first genitalia photo below). But the word appendage implies sticking out and while the top pair clearly lifted up like flaps the second pair seemed to be part of the surface of the subgenital plate, not separate and not liftable - so not what I would describe as appendages. The other specimens were similar but on these the pair of shapes was less distinct and if I'd looked at these first I probably wouldn't have even considered they might be the second pair of appendages.
The shape of the ventral appendages is also relevant and helps to convince me that they're not dubia. Barnard and Ross describe them for picicornis as being narrow, broadest at the base and for stagnalis rather pointed, narrow at the base. There is some variation in the shape of the 4 individuals I caught in 2020 but 3 look very similar to one another and one distinctly more pointed and also narrower at the base. I'm therefore tentatively identifying the pointed one as stagnalis and the rest as picicornis, but would welcome comments on this.
One of the ones I'm calling picicornis was very plain yellowy-orange brown which I presume is the form aurata described in Barnard and Ross. The one I'm calling stagnalis was also plain but darker and browner.
female Holocentropus picicornis, North Elmham Cathedral Meadows, 22nd August 2019
2 apparent female Holocentropus picicornis, North Elmham, 31st July 2020 - each genitalia photo corresponds to the insect above it
apparent female Holocentropus picicornis, North Elmham, 10th August 2020
Holocentropus stagnalis - This was one of the 3 Holocentropus caught in my garden moth trap on 31st July 2020. Compared to the others the ventral appendages were clearly more pointed at the tip and also narrowed at the base. I'm therefore tentatively identifying it as stagnalis, a new one for me if I'm right. It seems a bit of a coincidence that it turned up with 2 picicornis (assuming I was right about those), especially as I could see no other differences in the genitalia, so I would really appreciate confirmation (or correction) from someone who is better informed/experienced. It was a relatively plain individual but quite a different colour to the plain picicornis caught on the same night - much darker and browner compared to the pale yellowy-orange hues of the picicornis. There is a photo of a not too dissimilar individual at waarneming.nl.
apparent female Holocentropus stagnalis, North Elmham, 31st July 2020
Cyrnus flavidus - singles in the garden on 1st, 2nd and 30th June 2019 and 7th and 12th August 2020. The handbook describes this as a pale yellow species and the photos show a very plain-winged insect, but most of mine have not been at all plain. At first I wasn't finding it particularly easy to judge the character detailed in the guide for separating females from trimaculatus (the shape of the ventral appendages) - they never look exactly like the diagrams for either species. Other differences in female genitalia seemed to be apparent in the photos on the now-defunct trichoptera.insects-online.de website and these seemed at least consistent with the diagrams in the handbook, and were what I was relying on more. My confidence that I wasn't messing these up is supported by the fact that I've had the odd male that looks the same and should (in theory at least) be a more straightforward ID by genitalia, plus the fact that the trimaculatus I've recorded have tended to look darker. Despite no longer having access to the website the identification seemed to be a little easier in 2020.
female Cyrnus flavidus, North Elmham, 1st June 2019 - showing ventral view of partially-cleared abdomen
male Cyrnus flavidus, North Elmham, 2nd June 2019
female Cyrnus flavidus, North Elmham, 7th August 2020
female Cyrnus flavidus, North Elmham, 12th August 2020
Cyrnus trimaculatus - one caught in the garden on 30th May 2019 and one on 20th May 2020. This species seems to be scarcer here than the previous one though I have recorded it in each of the last 4 years.
male Cyrnus trimaculatus, North Elmham, 30th May 2019
female Cyrnus trimaculatus, North Elmham, 20th May 2020
Polycentropus flavomaculatus - A total of 16 caught in the garden between 1st June and 22nd September 2019 including a count of 6 on 24th June, and 20 between 22nd June and 11th September 2020. Also 3 at the meadows from 25th May 2019. The majority of Polycentropus that I catch are female, which is a shame as males are much easier to identify! I don't find it easy to see the subgenital plate on females (it seems to be transparent when cleared and only really visible when looked at from an angle, which makes it hard to judge how rounded the apex is) and as with the Cyrnus I find it difficult to judge the shape of the ventral appendages. Other features were indicated by arrows on the Scandinavian website and I generally felt more confident about the IDs of females in this genus after examining the area between the apices of the ventral appendages and comparing with images on that website. Sadly that site has now been taken down so in 2020 I had to pretty much rely on the subgenital plate and ventral appendages. The subgenital plate can be easier to see when the abdomen isn't fully cleared but either way I seemed to find it a bit easier to see this year.
female Polycentropus flavomaculatus, North Elmham Cathedral Meadows, 25th May 2019
female Polycentropus flavomaculatus, North Elmham Cathedral Meadows, 23rd June 2019
2 female Polycentropus flavomaculatus, North Elmham, 24th June 2019
male Polycentropus flavomaculatus, North Elmham, 29th June 2019
female Polycentropus flavomaculatus, North Elmham, 9th July 2019
female Polycentropus flavomaculatus, North Elmham, 22nd September 2019
male Polycentropus flavomaculatus, North Elmham, 22nd June 2020
male Polycentropus flavomaculatus, North Elmham, 24th June 2020 - showing genitalia (left and top) compared with Polycentropus irroratus (right and bottom) caught the same night
fermale Polycentropus flavomaculatus, North Elmham, 25th June 2020
fermale Polycentropus flavomaculatus, North Elmham, 3rd July 2020
fermale Polycentropus flavomaculatus, North Elmham, 16th July 2020
rmale Polycentropus flavomaculatus, North Elmham, 30th July 2020
fermale Polycentropus flavomaculatus, North Elmham, 14th August 2020 - with Polycentropus irroratus in last photo (right) caught the following night
Polycentropus irroratus - Singles caught in the garden on 1st, 24th and 30th June 2019 and then 6 in 2020 between 24th June and 15th August. As with the previous species the majority (two thirds) were females.
male Polycentropus irroratus, North Elmham, 1st June 2019
female Polycentropus irroratus, North Elmham, 24th June 2019
male Polycentropus irroratus, North Elmham, 24th June 2020 - abdomen shown above with Polycentropus flavomaculatus caught on same night
female Polycentropus irroratus, North Elmham, 17th July 2020 - shape of the subgenital plate only just discernible on the bottom photo
male (first) and female (second) Polycentropus irroratus, North Elmham, 24th July 2020
female Polycentropus irroratus, North Elmham, 6th August 2020
female Polycentropus irroratus, North Elmham, 15th August 2020
Polycentropus kingi - None. I've not found this species yet but there are plenty of records from Norfolk so it should turn up sooner or later. I assume I'm not overlooking it - the genitalia look like they should be relatively easy to pick out on both sexes.
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