Plectrocnemia conspersa - Caught in the garden on 6th June 2019 and possibly on 6th October but some doubt about the date/location of this one so I won't record it. More in 2020 with singles caught on 6 nights between 9th August and 12th October. A relatively distinctive species compared with most of the other Polycentropodidae but not so much compared with the other Plectrocnemia species (of which I think only geniculata is likely here in Norfolk). Differences in genitalia may be visible on live caddisflies but can be much easier with a dead specimen.
male Plectrocnemia conspersa, North Elmham, 6th June 2019
female Plectrocnemia conspersa, North Elmham, 24th August 2020
male Plectrocnemia conspersa, North Elmham, 12th September 2020
female Plectrocnemia conspersa, North Elmham, 23rd September 2020
Plectrocnemia geniculata - Although this species occurs in Norfolk I've never seen it here. However I did find 3 at different locations on Mull in June 2019.
female Plectrocnemia geniculata, Carsaig (Mull), 12th June 2019
male Plectrocnemia geniculata, Allt Molach (Mull), 13th June 2019
male Plectrocnemia geniculata, Ceann Chnocain (Mull), 13th June 2019
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Family PSYCHOMYIIDAE
Lype phaeopa - Females caught in the garden on 16th June and 2nd July 2019 and 22nd May and possibly 18th August 2020. I won't submit the last of these unless I receive advice to change my mind as I'm not entirely convinced the apparent indentation in the dorsal margin of segment IX isn't due to damage - the specimen was quite dried out and shrivelled when I examined it and on clearing I'm not entirely comfortable that the indentation is in exactly the right place (although it certainly doesn't seem to have the nice evenly curved margin of reducta). Until 2020 I was satisfied that all the female Lype I had caught (including 6 prior to 2019) were phaeopa, and I'm pretty sure the images in the now-defunct trichoptera.insects-online.de website had helped give me that confidence. But my only male (in 2019) was clearly reducta and in 2020 (without the benefit of being able to comapre with the website images) I'm identifying more reducta among the females too. I hope my past IDs were correct, but shall be checking these very carefully in future.
female Lype phaeopa, North Elmham, 16th June 2019
female Lype phaeopa, North Elmham, 2nd July 2019
female Lype phaeopa, North Elmham, 22nd May 2020
possible female Lype phaeopa, North Elmham, 18th August 2020
*** UPDATE JUNE 2021 ***
The Fenno-Scandinavian website is back up and running but at a different url and this casts some doubt on my previous identifications of this duo. The only feature for female Lype phaeopa vs. Lype reducta given in the Barnard and Ross handbook is the curvature of the dorsal margin of segment IX (slightly indented on phaeopa and evenly curved on reducta). The Fenno-Scandinavian website doesn't allude to this difference at all but does point to the vaginal sclerites on Lype phaeopa. It doesn't annotate this with any description of how they are relevant but I think the mere fact that they are highlighted implies they are of some importance to the identification. The photo of Lype redcuta on that website does not show any vaginal sclerites at all, so it was my presumption that presence of sclerites indicated phaeopa and absence indicated reducta. However if that is correct then all of the females shown here were phaeopa including the ones below that I labelled reducta on the basis of their nice smooth curve on the dorsal margin of segment IX. However, I'm not sure the abdomen of reducta shown on the Fenno-Scandinavian wesbite is fully cleared so that may be the reason why no vaginal sclerites are visible. So I am now unsure why the arrows are pointing to the sclerites on phaeopa. Is it as I imagined - presence or absence indicates phaeopa vs reducta (which would make Barnard and Ross wrong), or is it something to do with the arrangement or structure of these sclerites which we simply can't see on their photo of reducta, or is it in fact nothing to do with the phaeopa vs. reducta challenge at all but something else, like Lype spp. vs. Psychomyia spp. perhaps? Anyway, if Barnard and Ross is right (as far as I know it's pretty reliable) and I was wrong to assume the presence of vaginal sclerites pointed to phaopa, then I'm now left doubting some of my previous records of phaeopa which I think were at least partly influenced by this assumption. It is easy to make mistakes - and I think I have made mistakes - in assessing the curvature of the dorsal margin of segment IX. For example I have just examined a specimen from 2021 which appeared to have a clear indent. However as I began to prepare this for microscopic examination I realised that I was mistaken. The specimen, although quite freshly dead, had already started to dry up and segment IX had began to contract into what I presume was segement VIII. Thus what I was actually seeing was a step between the dorsal margin of segment VIII overlapping the dorsal segment of segment IX. It wasn't really possible to gauge the true shape of segment IX until it was fully cleared and even then it wasn't straightforward. It seemed to show a shallow indent, but I wasn't sure if it was a true structural indent or just a dent where it had been pushed in. Sure enough it proved to be the latter, and with a little bit of gentle pressure applied from the inside the dent came out and I was left with a nice evenly curved margin. I am now wondering whether some or even all my previous records of phaeopa that appeared to show an indented segement IX may infact have reducta... More study (and/or advice) needed on these I think, and hopefully I'll catch a few more males too.
Lype reducta - a male trapped in the garden on 21st July 2019 was my first ever record of this species but 2 females were caught in 2020 on 14th and 20th August.
male Lype reducta, North Elmham, 21st July 2019
female Lype reducta, North Elmham, 14th August 2020
female Lype reducta, North Elmham, 20th August 2020
Small Yellow Sedge Psychomyia pusilla - None - I've never seen this species but judging from the records on NBN Atlas it does occur in Norfolk (albeit much less common in the east of England than in the rest of the country).
Small Red Sedge Tinodes waeneri - One caught in the garden on 26th July 2019. I caught at least 1-2 of these annually for 4 years but none in 2020.
male Small Red Sedge Tinodes waeneri, North Elmham, 26th July 2019
Tinodes unicolor - None. I caught one in the garden in 2018. I don't think any of the other Tinodes species are very likely here.
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Family HYDROPSYCHIDAE
Hydropsyche instabilis - None. I've only ever identified this species at home once, in 2018 (and once in Cornwall the same year).
Hydropsyche siltalai - A total of 61 caught in the garden trap between 25th June and 13th September 2019. Smaller numbers in 2020 with 32 between 24th June and 22nd August. Also one at Weybourne on 5th July 2019 and one at Bintree Wood on 24th July 2020. Although some seem reasonably obvious (once the abdomen is cleared) I find some females can be quite tricky and have left a few unidentified. This species seems to average more strongly patterned and colder-toned than pellucidula though some pellucidula come very close. I'm yet to catch a siltalai that has been as plain (while fresh) or yellowy-buff toned as pellucidula can often be. I haven't caught enough of the others to comment on how they compare with the rest of the Hydropsyche species.
male Hydropsyche siltalai, Weybourne, 5th July 2019
female Hydropsyche siltalai, North Elmham, 19th July 2019
male and female Hydropsyche siltalai, North Elmham, 21st July 2019
female Hydropsyche siltalai, North Elmham, 24th July 2019
male Hydropsyche siltalai, North Elmham, 26th July 2019
male Hydropsyche siltalai, North Elmham, 31st July 2019
male Hydropsyche siltalai, North Elmham, 5th August 2019
female Hydropsyche siltalai, North Elmham, 7th August 2019
female Hydropsyche siltalai, North Elmham, 23rd August 2019<
female Hydropsyche siltalai, North Elmham, 25th August 2019
female Hydropsyche siltalai, North Elmham, 3rd September 2019
female Hydropsyche siltalai, North Elmham, 11th September 2019
female Hydropsyche siltalai, North Elmham, 13th July 2020
female Hydropsyche siltalai, North Elmham, 16th July 2020
male Hydropsyche siltalai, North Elmham, 22nd July 2020
male Hydropsyche siltalai, Bintree Wood, 24th July 2020
female Hydropsyche siltalai, North Elmham, 11th August 2020
Hydropsyche pellucidula - A total of 44 caught in the garden trap between 1st June and 26th September 2019 and 45 between 18th May and 22nd September 2020. I only sampled a small number of the Hydropsyche that I found at the meadows - but all 10 that I checked in 2019-20 were pellucidula (including 5 in the last week of May 2019 before I caught any at home). Also one at Hills and Holes on 21st May 2020 and one at Bintree Wood on 13th June 2020. As per my comments under siltalai, some individuals proved challenging to identify and any that were not identified with a reasonable degree of confidence are excluded. Although many pellucidula can be quite boldly patterned and closely resembling siltalai, many are more evenly speckled lacking the larger dark and pale patches and some are even plain with no obvious speckling at all - I've not found a fresh siltalai like that yet. Males are outnumbered by females in both species but especially so with pellucidula.
male and female Hydropsyche pellucidula, North Elmham Cathedral Meadows, 25th May 2019
female Hydropsyche pellucidula, North Elmham Cathedral Meadows, 31st May 2019
female Hydropsyche pellucidula, North Elmham, 5th June 2019
female Hydropsyche pellucidula, North Elmham, 23rd June 2019
female Hydropsyche pellucidula, North Elmham, 4th July 2019
female Hydropsyche pellucidula, North Elmham Cathedral Meadows, 7th July 2019
female Hydropsyche pellucidula, North Elmham, 10th July 2019
female Hydropsyche pellucidula, North Elmham, 19th July 2019
male Hydropsyche pellucidula, North Elmham, 21st July 2019
female Hydropsyche pellucidula, North Elmham, 29th July 2019
male Hydropsyche pellucidula, North Elmham, 30th July 2019
female Hydropsyche pellucidula, North Elmham, 25th August 2019
female Hydropsyche pellucidula, North Elmham, 21st May 2020
female Hydropsyche pellucidula, North Elmham, 12th June 2020
female Hydropsyche pellucidula, North Elmham, 17th June 2020
female Hydropsyche pellucidula, North Elmham, 18th June 2020
female Hydropsyche pellucidula, North Elmham, 6th August 2020
female Hydropsyche pellucidula, North Elmham, 24th August 2020
female Hydropsyche pellucidula, North Elmham, 12th September 2020
Hydropsyche contubernalis - None - I've only ever caught (and identified) one of these, at the meadows in 2018.
Hydropsyche angustipennis - None. I've caught this species twice at home, both in 2017, and once elsewhere. This species is well-recorded in Norfolk, probably about as much as siltalai and pellucidula, so it seems surprising that they don't turn up here more often.
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Family PHRYGANEIDAE
Speckled Peter Agrypnia varia - None. I've caught one of these at home, in 2016.
Agrypnia pagetana - One caught in the garden on 23rd July 2019 and one on 31st July 2020. I had these here on 5 occasions in 2016-17 but didn't record it in 2018.
female Agrypnia pagetana, North Elmham, 23rd July 2019
male Agrypnia pagetana, North Elmham, 31st July 2020
Trichostegia minor - None. I've only caught this species once, at Boughton Fen in 2016. Most Norfolk records seem to be concentrated in the Broads and the Brecks although it has been recorded NW of Norwich so there may be a chance of getting one round here.
Phryganea grandis - Singles trapped in the garden on 14th June 2019 and 24th June 2020. Also singles at the meadows on 31st May 2019 and 18th July 2020.
male Phryganea grandis, North Elmham Cathedral Meadows, 31st May 2019
male Phryganea grandis, North Elmham, 14th June 2019
male Phryganea grandis, North Elmham, 24th June 2020
female Phryganea grandis, North Elmham Cathedral Meadows, 18th July 2020
Phryganea bipunctata - Males caught at home on 31st May and 3rd June 2019 and a female on 26th May 2020. I've only caught and identified one here before, compared to 5 previous records of grandis.
male Phryganea bipunctata, North Elmham, 31st May 2019
male Phryganea bipunctata, North Elmham, 3rd June 2019
female Phryganea bipunctata, North Elmham, 26th May 2020
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Family BRACHYCENTRIDAE
Grannom or Greentail Brachycentrus subnubilus - none in 2019. I've only found this species once, in the Brecks in 2016, but there are records from the Wensum Valley so I may have a chance of finding it locally too.
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