Sunday 24 May 2020

Bad beetle day

Every now and then I have those days when I can't seem to identify anything. I don't think it is just a product of age, getting older, although memory plays a part. So yesterday I had a bit of a crack at some beetles and managed to make a mess of a few things, including commenting incorrectly on an online id. Often this is educative though. So following the brief discussion online I will now put a wee note next to Leistus spinibarbis in the Carabid keys that appendage colours are not reliable and that pronotum shape is the criteria to focus on. I tend to presume all the Leistus here are fulvibarbis, because that's all I've ever found, but in future I will check just that bit more carefully, fortunately this can be done without killing the animal, just by getting a half decent photo.

My other mess up was with this tiny weevil. I recognised that I had found it before. Unfortunately I hadn't put it with my Flickr collection, I need to be a bit more conscientious about doing that. So, thinking the rather hidden antennae were straight I headed off down the Apion road. And then got stuck. Going through all of Mark Gurney's excellent photos on his Flickr site (what a brilliant resource, especially when used with his guides, here ) I became increasingly frustrated that although I knew this was a common species I couldn't find it. Eventually I posted on the FB page and of course, it wasn't an Apion (thanks MF). Looking more carefully at my photo I could eventually see that the antennae that I had tried to tease out from beneagth the beast were indeed not straight.

Leiosoma deflexum - not an Apion. The numbered intervals are mm, it is tiny.

A common and widespread weevil of Ranunculus species.

Following this sort of mess up its important to regain confidence. A bit of digging in the garden, moving a bit of carpet - weed suppresent - and out popped what may well be the third county record of Amara aenea, (oh no the day got worse, wrong again! However, I did then redeem the situation by getting it right ovata/similata, I favour similata but could be wrong, and bonus, not previously found in the county either) both the other records were found within 10m of this one.

Amara aenea, ovata/similata slightly tricky to id.

A lot of the Amara look superficially very similar and can be tricky but I think all the relevant criteria can be seen from this photo, size c7mm. So I could let it go (but I do have a previous specimen). Misread the below, it obviously has a scutellary pore but I understood it incorrectly for some weird reason.

Also under the carpet a common but welcome Pterostichus niger. A species that has occasionally confused me in the past, from P.melanarius, but pronotom shape is a very good guide.

Pterostichus niger.

Confidence a little restored - or not, it all gets worse, see below.. 

I am trying to get some focus stacking to work using my digital microscope. The Olympus T4 does this automatically, the three beetles above are all focus stacked images, it works fine with live beetles when they stay perfectly still as Carabids in a pot often do. However, sometimes the T4 isn't the right tool for the job, unfortunately the Celestron didn't come with focus stacking software and the depth of field is pretty shallow. Photoscape X is a free tool that includes this. I use Photoscape 3.y to process all my images but the jump to X looks like a bit of a learning curve. However, I think I need to do this as I'm really struggling to get good enough images. Below are stacked images of Geodromicus nigrita from the T4, demonstrating its (or my) limitations.

Geodromicus nigrita - new to Orkney.

This landed on me at the stables on Thursday evening and with a bit of dextrous manouvering I managed to get it off my cycling glove and into a pot without losing it. It is tiny and black, and the T4 struggles with that combination often. The image below is with the Celestron, unstacked. But it would be easy to produce the range of images just need the software glue. There are good Youtube guides from the Photoscape folk so hopefully I should be able to learn to do this.

Geodromicus nigrita - hopefully I can get this confirmed.

I look at other folks' images online, there are some especially brilliant photographers out there consistently producing amazing images, however, I think that a permanent studio type set up with lights and tripods etc is required, I am assembling and dissembling my kit all the time. Ideally the FugifilmT3 with a macro lens, extension tubes/revering rings and some lights and diffusers would be the business for me but I would need to have a permanent set up. The cost is a bit scary. So I think I will try to improve what I do with what I've got. I wonder if a decent close-up lens to put on the Canon might help a bit though (CanonGX3) with the field photos. One problem with the T4 is the dreaded purple spot, a known issue, and still is with the T6, you have to work around it but it is very annoying, the Leiosoma above doesn't show it, but last week's Otiorhynchus porcatus does. Yes, you can process this out, hopefully Photoscape X might help with this.

Slug problems, yes they have started on my corgettes but I don't really mean that. On one of the local FB groups some photos were posted suggesting an ID of Arion vulgaris, an uncommon beast nationally and not recorded here. I had also taken some photos that afternoon and they also led me in that direction. But that seemed a bit unlikely. I posted on a national FB page and was given help, dissection suggested. I had another look at the slugs in question and found that actually, although they don't want to rock (Arion ater usually rocks back and forth if you stroke it) these are most likely Arion ater. 

Arion ater individual 1

 Arion ater individual 1

 Arion ater individual 1

 Arion ater individual 2

Arion ater individual 2 on left.

I'm hoping this little guy is Arion intermedius. (But it isn't, wrong again.) Arion subfuscus I think.

Here's another at another location with Deroceras reticulatum in the background - feeding on squashed worm sp....

Lastly on my identification rambles another battle with bumblebees. You would think that these should be easy, wrong, complete swines to id here in Orkney. Anyway, these two are right.

 Top two Bombus terrestris queen, a species that has become common here in the last few years.

Because it was huge, I couldn't get a picture of the face unfortunately to nail it, Bombus hortorum queen.

Bombus lucorum s.l. have been emerging from our garage but I've only got rubbish pictures. They are an aggregate of three species with B. cryptarum believed to be the predominate species from the species aggregate prevalent here but laboratory analysis required maybe to be certain.

 More of these this year, management regime is slowly increasing the diveristy of wild flowers in our Orkney Vole reserve, Cardamine pratensis.

Finding a new species of tree on the patch seems unlikely but today I walked right into the corner of the patch and there at the end of the line of trees along the burn by the bridge was this.

I think it is Alder.

Leaves look like Alder anyway.

Sunday 17 May 2020

Garden bird race and Otiorhynchus porcatus

55 species from the garden today and missed some that I really should have got, like Hen Harrier. However, Merlin, Goldeneye, Osprey and Arctic Skuas were nice.

Blurry Osprey, with (presumed) Brown Trout, raising a commotion.

 Dog walk (exercise) Ice, off patch unfortunately.

Star of the day was a new beetle for the garden and NFM too. Otiorhynchus porcatus, 5mm of quite distinctive weevil in one of the garden pitfalls and to be released the morn.

Otiorhyinchus porcatus.

Sunday 10 May 2020

Garganey and Megarthrus prosseni

Friday was a day off, overcast but still. I wandered about looking for things and birding. I ran the moth traps, but only two as the battery wasn't charged for one, forgot to turn the charger on. Nothing much in the traps, a few intruders included six Nicrophorus humator and five Stenophylax pernistus. More in vague hope than any real expectation in the dull conditions I put three colour tray traps out.

Afternoon I wandered down the track to have another look at The Shunan, and amongst the drake Gadwall and Shovelers suddenly from nowhere appeared a drake Garganey. There have been two previous occurences of this neat wee duck on the patch in the past, 2nd May 2014 and 23rd May 2015, on both those occasions I saw the bird from the car on the way to work. This time I was on foot, I also scented the chance of a garden tick. The dog and I turned and hiked back up the hill. From the favoured bench the duck remained in view, nice. It was still present yesterday and by late yesterday afternoon had been joined by a friend.

Three Gadwall, a Shoveler and a drake Garganey.

Not much in those colour traps, a Helophorus sp in the orange one, a large one, so either aequalis or grandis. There's a trick with these, shove a piece of paper under the elytra and view the last abdominal segement from underneath the beetle. Even then a bit tricky to see but grandis has nice regular cog teeth at the end of the segement whilst on aequalis it's all a bit random.

Helophorus aequalis.

There was little else in the traps except a small Staphylinidae. On examination this proved to be Megarthrus prosseni, awaiting confirmation, thanks again to Mike Hackston for his fabulous online keys.

Not the best photo, on H. grandis the "teeth" would be much more obvious.

The Helophorus was quite a big thing, 6 - 7mm the other beetle was a tad smaller.

Megarthrus prosseni I reckon.

Quite distinctive with the incised corners to the pronotum. I recall catching one of this genus before but I'm not sure it was this one. Looks as if there might not be previous records of this species here, I have the specimen anyway.

On Thursday I checked the pitfall traps by the dead Rook. The Rook has been festering for a few weeks. I'd put the traps in around the Rook following an online recommendation for the plan.

Good call, 13 Thanatophilus rugosus plus assorted Staphs and a Cercyon melanocephalus, most released, just kept sample Staphs to ID, not sure what the big shiny one is, on the list to "do".

Subsequently, the traps have contributed a few more of everything plus a rather cross and smelly Nicrophorus humator.

Nicrophorus humator, on top of the actinic trap.

 Other trap intruders - Psychodidae - 90 odd species, tricky beggars best left alone, lots of these.

Stenophylax pernistus, strictly requires gen det but on distribution most likely this species.

Common Pug, new moth for the year on Friday night.

Anthrocoris nemorum, beaten from willow.

Expect a swarm sometime soon, when it warms up probably, Fever Fly, Dilophus febrilis.

For the first time I had my first Sedge Warbler of the year when it was snowing. Bit of snow today, it actually settled for a bit.

Meadow Pipit

Lesser Redpoll from kitchen window, three ringers locally have done 150 of these this year.

Brown Hare from the car today.