SUBFAMILY TYPHLOCYBINAE
Alebra albostriella - 4 caught in my garden moth trap and 4 found at the Cathedral Meadows (one to light and the others on Oak) between 26th July and 9th October 2019. Having averaged 4 a year for the last 3 years it was a surprise not to catch any at home in 2020 and only one at the meadows (3rd August). The dark spots at the base of the tibial spines that are characteristic of this species were observed to be present even though they don't show up very well in the photos.
Alebra albostriella, North Elmham Cathedral Meadows, 26th July 2019
Alebra albostriella,
North Elmham Cathedral Meadows, 3rd August 2020
Alebra coryli - 3 in my garden moth trap on 12th July 2019 followed by singles on 19th July and 6th August. These consisted of 2 males (sternal apodome checked on one) and 3 females. Just 2 (both females) here in 2020, on 4th July and 29th August.
Alebra coryli,
North Elmham, 19th July 2019
Alebra coryli,
North Elmham, 29th August 2020
Alebra wahlbergi - One at the Cathedral Meadows on 7th July 2019, a new leafhopper for me.
Alebra wahlbergi,
North Elmham Cathedral Meadows, 7th July 2019
Dikraneura variata - One to my garden moth trap on 10th July 2019, only my second.
Dikraneura variata,
North Elmham, 10th July 2019
Empoasca decipiens - 3-4 in my garden moth trap between 29th July and 14th August 2019. What was probably another was trapped on 3rd November but showed dark eye-patches in the photo, something I can't find any reference to occuring on this species. Sadly it escaped after I had taken a single photo so unsure of its identity I asked Tristan Bantock via Twitter: he advised that it was probably this species. Subsequently I recorded another Empoasca which showed dark eye-patches in photos but these were not present in life - some kind of weird photographic effect - so perhaps that's what had happened here too. In 2020 caught in the garden on 7th and 16th January and then 3 between 14th July and 26th September. Also caught in Cornwall on 6th and 8th October 2020. In theory decipiens should be easy to separate from vitis as the latter has a clear whitish cell through the wing. In practice some individuals have a vaguely paler cell that is hardly discernible, and a couple of such individuals in 2020 proved on dissection to be male vitis. This makes me wonder if I might have misidentified some decipiens that were really indistinct examples of vitis. Latterly I've been checking them a bit more carefully but it's plausible that there may be some errors among my earlier records. There have been a few that I've ended up leaving unidentified.
Empoasca decipiens,
North Elmham, 29th July 2019
probable Empoasca decipiens,
North Elmham, 3rd November 2019
Empoasca vitis - The commonest leafhopper in my garden with 54 between 22nd April and 5th November 2019 (peaking at 9 on 26th August) and 72 between 10th April and 16th November 2020 (peaking at 11 on 11th August). A handful of records elsewhere including at the Cathedral Meadows, the adjacent Millenium Wood, Row Heath (West Runton) and in Cornwall. As well as the main peak in August they seem to have other smaller peaks in April and October, as shown in the following chart of my records.
distribution of my records to date of Empoasca vitis in Norfolk
Empoasca vitis,
North Elmham Cathedral Meadows, 22nd April 2019
The following two are examples where the pale cell was very indistinct (especially on the first one) although it could just be made out with a really careful look:
male Empoasca vitis,
North Elmham, 8th November 2020
male Empoasca vitis,
North Elmham, 16th November 2020
Kybos sp. - This is a really tricky genus and for the majority of species only the males can be identified. It may be possible to narrow females down to 2 or 3 species but as it seems a bit pointless going to the effort and then still not ending up with a full ID I'm only now retaining the males. Even the males are not without some considerable challenges though - I am using the RES key to identify them but many don't seem to conform as neatly as the key suggests they should. I am slightly unsure if I am interpreting the anatomy correctly, particularly in relation to the apodemes of the first and second abdominal sterna. There were fewer Kybos in general in 2019/20 than there were in 2018, with only 7 unidentified females in the garden moth trap all year (I had as many or more than that in a night on 3 occasions in 2018) and just 5 in 2020.
Kybos betulicola - Male Kybos betulicola and Kybos smaragdula are readily separable from the other similar-looking Kybos by the arms of the aedeagus, but separating them from one another is trickier. I am yet to identify smaragdula and given the proximity of Birch to my moth trap betulicola is perhaps the most likely of the two (smaragdula is mainly on Alder), however I am not absolutely happy with my IDs of what I think are betulicola. The shape of the apodeme of the second abdominal sternum fits the description of betulicola but I don't think it quite matches the illustration perfectly, although that may be because I'm misinterpreting which bit is which. At least some of them have a pair of greyish spots on the vertex which seems to favour betulicola but I'm not sure about the appendages of the anal tube. These should be suddenly narrowed to a thin spine at the apex on betulicola (and may or may not be on smaragdula) but if there is a spine on most of the specimens I've examined then it's really miniscule - only one of them in 2019/20 had any discernible spine (the last one shown below). Any help with these would be welcome! Anyway, I caught candidates for this species at home on 10th July and 23rd September 2019 and 2 on 22nd September 2020 (after 8 here in 2018); also one at Swanton Great Wood in August 2019 and one at Whitwell Street in September 2020.
probable Kybos betulicola,
North Elmham, 10th July 2019 (showing aedeagus, anal tube appendages and apodemes)
probable Kybos betulicola,
North Elmham, 23rd September 2019 (showing apodemes and aedeagus/anal tube appendages)
probable Kybos betulicola, Whitwell Street, 3rd September 2020 (showing apodemes and aedeagus/anal tube appendages)
2 probable Kybos betulicola,
North Elmham, 22nd September 2020 (each insect followed by its anal tube appendages (you can see the aedeagus there too in the second one) and its apodemes)
Kybos butleri/rufescens - None. I've never found a confirmable male of either of these two species but in 2018 I caught a female that keyed to one or the other, so one of the two must occur locally.
Kybos populi - I nearly passed this leafhopper off as an Empoasca but couldn't immediately decide which one it was when I took it out of my moth trap on 25th October 2019. Good job I took a closer look as it turned out to be this plainer Kybos species which I'd never identified before. Fortunately it was a male which meant I could double-check the ID with reference to its genitalia. Sadly it wasn't in a good way when I emptied the trap early morning and couldn't stand up straight for its photo...
Kybos populi,
North Elmham, 25th October 2019
Kybos strigilifer - Like betulicola, these have provided no little amount of head-scratching when examining them under the microscope and comparing with images and descriptions in the key. But unlike betulicola, I ended up satisfied that I was getting them right. The details of the crest on the aedeagus can be incredibly hard to see even under high magnification, and the extent of the spine on the tip of the anal tube appendix seems to be quite variable, but after examining a number of specimens I felt confident enough that strigilifer was the correct ID for nearly all the specimens with divergent arms to the aedeagus (unlike betulicola where the arms are parallel, although both types can break easily and resemble the other in this respect). I caught 10 males in my garden moth trap between 21st July and 3rd September 2019 and just 2 in 2020, on 8th and 19th August. I said I was confident about "nearly all" and it was the last of these that I have some doubt about. The serrated crest on the aedeagus was clear enough on side view and just about visible on ventral view under high mag but it did not project to sides; the tapering shape equivocal but a bulge below appendages is as illustrated for strigilifer (not mentioned in key so not sure if that's significant?). However there were no spines on anal appendages, so could this be calcarata?
Kybos strigilfer,
North Elmham, 30th July 2019 (and its aedeagus from back and side and anal tube appendages)
Kybos strigilfer,
North Elmham, 31st July 2019 (and its aedeagus from back and side)
Kybos strigilfer,
North Elmham, 9th August 2019 (and its anal tube appendages and aedeagus from back and side )
Kybos strigilfer,
North Elmham, 9th August 2019 (and its apodemes, anal tube appendages and aedeagus from back and side )
possible Kybos strigilfer,
North Elmham, 9th August 2019 (and its aedeagus from side and back and anal tube appendages)
Kybos virgator - None. I found this species at the meadows in 2018.
Eurhadina concinna/ribauti - The only confirmed record I've had of this species was a male ribauti here in 2018. So far as I know this pair of species can only be reliably separated by reference to the male genitalia, so unless someone can advise otherwise a female beaten from Oak at the meadows on 19th August 2020 must remain unidentified. Indeed even getting it this far wasn't straightforward as the spot on the external apical vein was so indistinct I couldn't tell if I should interpret it as small spot, small dash, or no clear marking, however I eliminated loewii on size (3.9mm) and kirschbaumi on the absence of Sessile Oak in the area (which I realise isn't a wholly satisfactory means of identification as these things can stray).
Eurhadina concinna or Eurhadina ribauti, North Elmham Cathedral Meadows, 19th August 2020
Eurhadina pulchella - A new species for me but there were at least 4 in a variety of guises coming to light at Swanton Great Wood on 27th August 2019.
3 forms of Eurhadina pulchella, Swanton Great Wood, 27th August 2019
Next page: more leafhoppers
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