Medium Sedge Goera pilosa - A total of 8 in the garden trap between 23rd June and 30th July 2019 and 11 between 17th June and 8th August 2020; also one at the meadows on 22nd August 2019.
male Medium Sedge Goera pilosa, North Elmham, 23rd June 2019
female Medium Sedges Goera pilosa, North Elmham, 10th July 2019
female Medium Sedge Goera pilosa, North Elmham, 24th July 2019
female Medium Sedge Goera pilosa, North Elmham, 17th June 2020
female Medium Sedge Goera pilosa, North Elmham, 20th June 2020
Silo nigricornis - None. There are loads of records of this species in Norfolk so it is perhaps surprising that I haven't come across it yet.
Silo pallipes - Female in the garden trap on 10th July 2019 and 25th June 2020. I'd caught this species twice before, both in 2017.
female Silo pallipes, North Elmham, 10th July 2019
female Silo pallipes, North Elmham, 25th June 2020
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Family LEPIDOSTOMATIDAE
Crunoecia irrorata - Singles caught in the garden on 21st July and 25th August 2019 and 18th and 31st July 2020. Also a male netted between Carsaig and Rubha Dubh on Mull on 10th June 2019.
male Crunoecia irrorata, between Carsaig and Rubha Dubh (Mull), 10th June 2019
male Crunoecia irrorata, North Elmham, 21st July 2019
female Crunoecia irrorata, North Elmham, 25th August 2019
male Crunoecia irrorata, North Elmham, 18th July 2020 - showing distinctive genital capsule
female Crunoecia irrorata, North Elmham, 31st July 2020
Small Silver Sedge Lepidostoma hirtum - 3 caught in the garden on consecutive nights 27th to 29th August 2019 and 6 between 14th August and 8th September; elsewhere one at Swanton Great Wood on 27th August 2019 and 2 at the meadows on 8th September 2020. All 12 were females and I didn't alwasys find it easy to eliminate Lepidostoma basale (although as far as I know that species doesn't occur in East Anglia). The Barnard and Ross Handbook points to a single feature on its diagrams of the genitalia, the shape of the subgenital plate, and on at least a few individuals (especially the first one in 2020) this looked better for basale. But there are other differences in the diagrams, although when they're not arrowed or drawn attention to in the text I'm never sure if these are differences between the species or just differences between the specimens used as a basis for the diagram. Anyway, hirtum is illustrated with wide shoulders (not a technical term!) before the tip of the abdomen, and all mine shared this characteristic - the basale diagram in the Handbook shows much less of a step. When I first encountered this problem I found a photo of hirtum genitalia online that looked similar (I can't find it now - maybe it was on the defunct website but I thought it was more recent than that), so given basale is so unlikely here I think it's safe to call them all hirtum. Photos of the genitalia of the most troublesome individual are below, along with a more straightforward one. Please let me know if you disagree.
female Small Silver Sedge Lepidostoma hirtum, Swanton Great Wood, 27th August 2019
female Small Silver Sedge Lepidostoma hirtum, North Elmham, 28th August 2019
female Small Silver Sedge Lepidostoma hirtum, North Elmham, 29th August 2019
presumed female Small Silver Sedge Lepidostoma hirtum, North Elmham, 14th August 2020 - showing what looks like a very flat rounded tip to the subgenital plate (as on L basale); this happened to be the first time I've found the corpus bursae on a caddisfly - the ductus bursae is very thin and delicate so I assume this normally breaks and gets lost during the preparation (as far as I know this isn't helpful for identification but was of interest to me
female Small Silver Sedge Lepidostoma hirtum, North Elmham, 24th August 2020 - this one shows a subgenital plate with a longer more narrowly rounded tip as I would expect on L hirtum
female Small Silver Sedge Lepidostoma hirtum, North Elmham, 30th August 2020
female Small Silver Sedge Lepidostoma hirtum,
North Elmham Cathedral Meadows, 8th September 2020
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Family APATANIIDAE
Apatania muliebris - None. Judging from the NBN Atlas maps this species occurs in the Wensum Valley but I've not come across it here or anywhere else yet.
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Family LIMNEPHILIDAE
Drusus annulatus - None. The NBN Atlas maps indicate that this species has occurred nearby but I haven't found it yet.
Brown Sedge Anabolia nervosa - One caught in the garden on 22nd October 2019 and 4 between 21th and 21st October (I had caught 8 here in 2018). Elsewhere 2 caught at the meadows on 12th October and 4 there on 1st November 2019 and 2 at Stiffkey on 16th October 2020. The other member of this genus, Anabolia brevipennis, occurs in Norfolk but there are no records on the NBN Atlas for the Wensum Valley area.
male Brown Sedge Anabolia nervosa, North Elmham Cathedral Meadows, 12th October 2019
male Brown Sedge Anabolia nervosa, North Elmham, 21st October 2019
male Brown Sedge Anabolia nervosa, North Elmham Cathedral Meadows, 1st November 2019
Brown Sedge Anabolia nervosa, North Elmham, 12th October 2020<
Brown Sedge Anabolia nervosa, Stiffkey, 16th October 2020
Mottled Sedge Glyphotaelius pellucidus - A total of 56 between 1st May 31st October 2019 and 39 between 8th May and 29th October 2020. A total of 22 at the meadows on 7 dates including 15 on 25th May 2020 and elsewhere singles at Swanton Great Wood, Row Heath (West Runton), Whitwell Street and Tresidder (in Cornwall). My records of this species show two clear peaks, one from May to early June and one from late July to October (especially late August to late September) but I've had a few odd records throughout the diapause in June-July.
Mottled Sedge Glyphotaelius pellucidus, North Elmham, 1st May 2019
Mottled Sedge Glyphotaelius pellucidus, North Elmham Cathedral Meadows, 25th May 2019
Mottled Sedge Glyphotaelius pellucidus, North Elmham Cathedral Meadows, 15th May 2020
Grammotaulius nigropunctatus - Singles caught in the garden trap on 12th September 2019 and 11th and 23rd April 2020 (I'd had 3-4 in each of the previous 3 years). Also one at Hills and Holes on 21st May 2020. There are no records of the much scarcer Grammotaulius nitidus showing in the NBN Atlas for the Wensum Valley although it does occur in the Broads and has been recorded in the Norwich area.
male Grammotaulius nigropunctatus, North Elmham, 12th September 2019
male Grammotaulius nigropunctatus, Hills and Holes, 21st May 2020
Next page: more Limnephilidae
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