Ceraclea albimacula - females caught in the garden trap on 16th and 17th July 2019 were identified as this species although the test version of the upcoming caddis guide says this species should have a white dorsal spot whereas the photos of these two clearly show that this spot was not white. Having said that I spent a fair bit of time checking the genitalia against the images on the now-defunct trichoptera.insects-online.de website and I felt confident at the time. These are difficult though, so maybe I got this wrong? There was another individual that I wasn't so confident about on 29th July - I thought it was this species but wasn't totally sure. Also recorded in 2017 and 2018 but none in 2020.
female Ceraclea albimacula, North Elmham, 16th July 2019
female Ceraclea albimacula, North Elmham, 17th July 2019
Ceraclea fulva - Females caught in the garden on 26th and 29th July 2019 were probably this species, and if so they would be new for the garden. I had felt reasonably confident about the previous albimacula (above) but these two caused me more problems. I examined them one after the other so was able to compare their genitalia side by side - there were differences between them but the differences between the two were pretty tiny. Externally both were similar to one another, and different from the above albimacula, but I'm not sure how variable/overlapping the two species are externally - there are very few images online and for the most part it isn't clear that those that are online are necessarily labelled correctly. I've not been able to establish whether the pale transverse line in the discal area is significant or not. Anyway, after spending hours staring down a microscope and comparing what I could see with the diagrams in the RES Handbook and the images on trichoptera.insects-online.de (where albimacula was indexed as alboguttata but shown as albimacula on the page itself), I put the first down as fulva but left the second unidentified. Coming back to it with fresh eyes at the end of the year, with only poor photos of the genitalia and not the actual bits, I shifted more towards them both being fulva, but still didn't feel confident enough about that to record them as such. Maybe when I've got more experience and/or references for these I'll be able to come back and be more confident, but for now I think it best if I don't record these. A complete blank on Ceraclea in 2020 didn't help expand my experience. Comments welcome...
probable female Ceraclea fulva, North Elmham, 26th July 2019
probable female Ceraclea fulva, North Elmham, 29th July 2019
probable female Ceraclea fulva, North Elmham, 29th (left) and 26th (right) July 2019 - lateral, 2 dorsal and ventral views of genitalia
Ceraclea nigronervosa - None. Judging from the NBN Atlas there are a few records of this species from the Wensum Valley but I don't think I've come across any yet.
Ceraclea dissimilis - At least one of 2 similar caddisflies caught on 23rd July 2019 proved to be a female of this species (the second wasn't retained). There were at least 2 other caddisflies that I wasn't able to put a definite name to that resembled this species externally.
female Ceraclea dissimilis, North Elmham, 23rd July 2019
Ceraclea senilis - None. Although there appear to have been quite a lot of records of this species in Norfolk not many come from the Wensum Valley so perhaps it's no surprise I haven't found any yet.
Leptocerus tineiformis - A total of 16 in the garden moth trap between 24th June and 5th August 2019 but fewer in 2020 with 8 between 23rd June and 6th August. Elsewhere 3 at the meadows on 30th June and 4 at Weybourne on 5th July 2019. I identified most of these in the field in 2019 and only checked the genitalia of a selection; as such it was possible (if very unlikely) that I might have overlooked the odd lusitanicus among them so I checked all but one in 2020.
male Leptocerus tineiformis, North Elmham, 4th July 2019
female Leptocerus tineiformis, North Elmham, 23rd June 2020
female Leptocerus tineiformis, North Elmham, 30th July 2020
Mystacides azurea - one of the Black Silverhorns: a female trapped in the garden on 3rd August 2019 was my second identified here following one in 2016. 2020 was a better year with 3 between 26th June and 11th August 2020. The first individual in 2020 showed a slightly cranulated apical excision in ventral appendages but very much less excavated than shown in the diagram of nigra in the Bernard and Ross Handbook so I think the ID as azurea is safe (the small lower appendages were also narrow as in diagram of azurea not as in nigra).
female Mystacides azurea, North Elmham, 3rd August 2019
female Mystacides azurea, North Elmham, 26th June 2020
female Mystacides azurea, North Elmham, 6th August 2020
female Mystacides azurea, North Elmham, 11th August 2020
Mystacides nigra - None. This (the other Black Silverhorn) occurs in the Norfolk including the Wensum but going on the number of dots on the NBN Atlas it isn't nearly as common. No surprise then that I haven't found one yet.
Grouse Wing Mystacides longicornis - 4 caught in the garden between 29th June and 7th August 2019. I had nearly 60 here over the previous 3 years so this was a poor year. Elsewhere in 2019 4 next door on 7th-8th August, singles at the meadows on 23rd and 30th June and one at Swanton Great Wood on 27th August. The 2020 sesason kicked off with 4 at the meadows and 4 at home on 23rd June, followed by another 9 at home up to 10th August.
Grouse Wing Mystacides logicornis, North Elmham Cathedral Meadows, 23rd June 2019
Grouse Wing Mystacides logicornis, North Elmham Cathedral Meadows, 23rd June 2020
Oecetis ochracea - None. One in the garden on 16th September 2020, my first here since 2016. Also one at the meadows on 17th May 2020.
female Oecetis ochracea, North Elmham Cathedral Meadows, 17th May 2020
female Oecetis ochracea, North Elmham, 16th September 2020
Oecetis lacustris - One at the meadows on 23rd June 2020 but although I recorded this species at home 3 times in 2016-17 I've not caught any here since then.
female Oecetis lacustris, North Elmham Cathedral Meadows, 23rd June 2020
Oecetis furva - None. Judging from the number of dots on the NBN Atlas this is much the scarcer of these 3 Oecetis species in Norfolk, but it was the only one of the 3 that I caught here in 2018.
That's it for the caddisflies - you can return to the Caddisfly index
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