Information about identifying this family has been quite hard to find. The information for each species at the British Bugs website is of course extremely helpful, but not all the species are covered which has sometimes left me with a bit of doubt about the identifications. I only recorded them if they check out fully with the criteria given at British Bugs but not knowing what the species that weren't covered should look like always made me a bit nervous. More recently I'm grateful to have been sent draft keys to British Heteroptera and these have enable me to make more progress with difficult families like this one. Only the more recent records below (those identified since spring 2020) have benefited from these, and some have been pretty challenging even with the key! As always, any corrections or other help always welcome.
Anthocoris confusus - One in my garden moth trap on 14th August 2020. I'd previously identified one (in 2018) at the meadows but after finding other similar species in exactly the same place shortly afterwards (and having initially got in a muddle with their identification) I decided my earlier record should be treated as uncertain. But this this one certainly showed a dull band along the inner edge of the embolium and the inner corner of the cuneus was also dull, so I think it's good.
Anthocoris confusus, North Elmham, 14th August 2020 with close up showing the contrast between dull and shiny parts of the wing (it was easier to see in life than in the photo!)
Anthocoris nemoralis - One in my garden moth trap on 14th January 2019 was the first of this species that I have identified although I may have overlooked it before. 3 records at the Cathedral Meadows between 8th March and 3rd August 2019, all taken from Broom (growing under Oaks). As the 3 at the meadows were on Broom, and especially as the similar Broom-feeding Anthocoris sarothamni was found in the same patch of Broom (see below) I was keen to ensure I was especially careful to eliminate that species. One in my garden moth trap again on 17th February 2020.
Anthocoris nemoralis, North Elmham, 14th Juanuary 2019
Anthocoris nemoralis, North Elmham Cathedral Meadows, 8th March 2019
Anthocoris nemoralis, North Elmham Cathedral Meadows, 8th April 2019
Anthocoris nemoralis, North Elmham, 17th February 2020
Common Flower Bug Anthocoris nemorum - Recorded at the Cathedral Meadows on 8th April and 5th July 2019. Nymphs recorded there on 19th August and 11th September 2020, both raised to adults in order to confirm their identity (one taken from Oak, the other from Bramble).
Anthocoris nemorum, North Elmham Cathedral Meadows, 8th April 2019
Anthocoris nemorum nymph, North Elmham Cathedral Meadows, 19th August 2020
Anthocoris nemorum nymph, North Elmham Cathedral Meadows, 11th Septenber 2020
Anthocoris nemorum, 14th September 2020 (same individual as nymph above from 11th September)
Anthocoris sarothamni - Taken from Broom at the Cathedral Meadows on 22nd February and 26th April 2019, the first times I've identified this species. Most of the Broom was removed by the railway company later in the year and the remnants have been much less productive so far.
Anthocoris sarothamni, North Elmham Cathedral Meadows, 26th April 2019
Cardiastethus fasciiventris - None. I found this species at the meadows in 2018.
Orius vicinus - An Orius sp. caught in my garden moth trap on 31st July 2020 and 2 found at the meadows on 16th September and 30th October (on Bindweed and Oak) provided a bit of an identification challenge. They were all females and keyed to either Orius majusculus or Orius vicinus, which are supposed to differ by overall size and the length of the copulatory tube. All 3 were comfortably within the size range for vicinus (2.2mm to 2.4mm: the key gives 2.2 to 2.5 for vicinus and 2.6 to 3.2 for majusculus) but the key advises against placing "undue reliance" on the size distinction. I'm not sure if that means you *have* to check the copulatory tube to be sure, or just that you should additionally check the copulatory tube for those at the larger end for vicinus or smaller end for majusculus. The copulatory tube is a bit of anatomy I've not needed to look at before and proved a bit challenging to find and/or recognise. The first one I looked at (not the first I caught, the one from 16th September) showed a darkened squiggly line in the right place (in the intersegmental membrane between the seventh and eight abdominal segments) but it seemed quite a bit longer than the illustration in the key for vicinus - more like majusculus.
Orius sp. and its 7th and 8th segmeents, North Elmham Cathedral Meadows, 16th September 2020
Could it be a small majusculus then? I wasn't convinced - this darkened line really didn't look like a tube, and it hadn't taken up the stain at all which is odd as the key says the tube should be visible on stained specimens. So I stepped up the magnification and had a really careful look. On closer inspection there was a tube-like structure at the top left edge of the darkened line, and this had taken up some stain, and was pretty much the right size, shape and position as it should be on vicinus.
part of the 7th segment of presumed Orius vicinus, North Elmham Cathedral Meadows, 16th September 2020
The next one I looked at (the first one I caught, in my garden on 31st July) seemed to have a stained tube-like structure in the same place of a similar form but much easier to see this time.
presumed Orius vicinus, North Elmham, 31st July 2020 - showing 7th segment
On the last one the seventh segment got a bit damaged as I cleared and cleaned it, with a break right across where the copulatory tube should be. So I don't think I can call this either way based on the copulatory tube, but as it was also the smallest one (2.2mm) I think it's probably safe to call this one vicinus too.
presumed Orius vicinus, North Elmham Cathedral Meadows, 30th October 2020 - showing damaged 7th segment
Having spent far too much time sorting these out and wishing that at least one of them had been a male I realised that another bug I had caught at home on 11th August 2020 was probably one of these too, not what I had initially identified it as. Fortunately I still had the specimen, and it was a male! Of course there is no reason to assume it must have been the same species as the others but nevertheless it was very reassuring to see that this one had an unquestionably vicinus paramere, boosting my confidence that the female were correctly identified as this species too.
male Orius vicinus, North Elmham, 11th August 2020 - showing paramere
Prior to these there were 2 additional similar bugs which I swept from White Dead Nettle at the meadows on 10th April 2020. One looked a lot like the Orius above but the other was almost black and smaller. When I retained and photographed them I assumed they were different species but intriguingly when I came to examine the specimens the black one appeared much paler than it had looked when it was alive, though still obviously darker than the other one. They both keyed the same way, or I should say miskeyed, becuase my initial attempts to identify them took me to a species in a different genus which I now realise was incorrect. Upon reaching a conclusion I discarded the specimens, but as soon as I processed the first couple of Orius above I realised that I must have gone wrong with the earlier specimens. I sifted through the specimens in my discard pot (which I always keep for a while, just in case of these sorts of eventualities) but the tiny size meant it was hard to find them. I eventually found the darker example, but it was in poor condition. I had indeed made a mistake - it was, I now believe, another female Orius but, as I had remembered, smaller than the ones above - just under 2mm (~1.95mm). There was no sign of any hairs at any of the corners of the pronotum but it was in poor condition now so I can't be sure these weren't all broken off. That being so I can't rule out Orius nigra. The only other species for which the key draws attention to dark colouration is horvathi, but it suggests finding a male to confirm that species (there are no records of horvathi on NBN Atlas, so perhaps not so likely?). My guess is that the larger one (2.3mm) was another vicinus but of course I can't be sure of that without re-checking the specimen so won't be recording it.
unidentified Orius sp., North Elmham Cathedral Meadows, 10th April 2020
Temnostethus pusillus - One in the garden moth trap on 27th September 2020, the first time I've identified this species.
Temnostethus pusillus, North Elmham, 27th September 2020
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