Syrph's Up!

Today I took a second wander up to the woods above the River Conon in search of more leaf litter lovelies. I somehow pulled my back at the end of December and it's been giving me a small degree of grief ever since. Today though, it was bad - I ended up just sitting on the ground and checking the leaves within arm's reach. Happily, I struck lucky and found a few hoverfly larvae.

This is a Syrphus, I don't know which one and I'd have to rear it through to find out. It was completely inactive, so I guess it's fully fed and settled down to pass the winter in a state of dormancy, or aestivation* hibernation as it's more properly known. Had I have thought to check the underside I probably would have seen an entirely pale belly, showing that it had voided its last meal and not eaten since. Actively feeding larvae show a dark gut-line. 

Just a few more leaf turns and I found myself looking at this fine fella, another Syrphus hoverfly

This individual showed signs of life, most notably when I dazzled it several times with the camera flash which elicited a slo-mo shake of the head and general hunching of shoulders. Yeah, I get that. I'm just the same first thing in the morning. 

I changed location, and sank awkwardly to my bum maybe fifty feet further into the trees. Bugger this! Happily, within just a few minutes I found a third Syrphus larva.

This bad boy was very definitely active, rearing up and squirming across the leaf surface. Apparently Syrphus are obligate aphid eaters, they don't have the mouthparts to successfully predate other dipteran larvae. So, quite why it was still active instead of aestivating* hibernating is anyone's guess. 

It struck me that the inactive larva was on a windswept, dry, surface leaf. The barely active larva was on a mostly dry leaf, though on the wetter underside, whilst the fully active larva was on a wet leaf. My thoughts are that the first larva will need to relocate to a more sheltered and moist site pretty soon, same with the second larva. Apparently overwintering hoverfly larvae are very sensitive to light levels, choosing to hide from brightness, and to humidity levels, avoiding desiccation by sunlight or cold winds. Presumably keeping out of the elements is also keeping out of sight for foraging Robins too, always a good move (I currently have a Robin that is hellbent on flying through my barely open window, then shitting over everything in it's panic to escape back outside. It's a repeat offender, I may have to put up some midge mesh. Anyway...)

My last post related to finding my first ever Melanostoma larva, plus the Lonchoptera larva they munch on. Today I found another favourite snack of the mighty Melanostoma

This is a Lauxiniid larva, a family of rather small flies. The outer cuticle is too tough for Syrphus (though they occasionally try it anyway) but not so for Melanostoma. And if you thought the pic was cute, just wait until you see the video clip 

If you watch cxarefully, you can see the cephalic skeleton in action as the larva feeds. This larva is approximately 3mm in length, so I'm quite pleased the camera picked up so much detail. I did briefly wonder if I could ID them to species by the shape and form of their cephalic skeleton. Turns out there are lots of them and I don't have sufficient detail in this short clip to enable a definitive ID. One for next time, maybe.  

Just because this is playing as I'm writing this, I give you The Manics and Indian Summer. Enjoy

* 'aestivation' is incorrect, see Mark's comments below for full explanation.

Leaf Litter Lovelies

Just two days ago I heard about the existence of the UK Hoverflies Larval Group on Facebook. I'm not at all sure quite how this Group managed to slip beneath my radar, but I immediately requested to join up and was quickly welcomed into the (admittedly rather niche) world of  hoverfly larva. What have I let myself in for? Or maybe it's better to ask, what have they let themselves in for...

Today I spent a rather pleasant hour or so grubbing about in the mostly Sycamore leaf litter in search of early stage hoverflies. I found lots of slugs, more Arion intermedius in an hour than I usually find in a year, plus lots of these slender annelids (?) 

I don't know if this is an annelid or not, but it seems to be segmented and has what could be a clitellum

Edit - I think this may be a Potworm (Enchytraeidae), about which I know nothing!

In terms of abundance, the next commonest creatures I encountered were these larvae. I think they are Tipulidae because they have weirdly enlarged projections around the spiracles. Despite finding loads of these today, all of my pics are crap. A selection follows

Craneflies have silly faces on their bums - who knew?!?

Presumably different species have different faces. I wonder if anybody's done a photo gallery of them all yet?

But I wasn't here for worms and cranefly larvae, I was after hoverfly larvae. Luckily for me, I found one

This green beauty is a hoverfly larva from the genus Melanostoma. As far as anyone seems to know, these have to be reared through to adulthood before they can be identified to species. At this time of year most other hoverfly larvae are probably fully fed and ready to overwinter, but Melanostoma are winter active. Not that it's very wintery here at the moment, it's decidedly mild in fact. A short while later I came across the first of several Melanostoma snacks 

A bizarre fly larva from the genus Lonchoptera

I see these tiny trilobite things quite often, they really are fascinating little creatures. I managed to make a short video clip of this one as it scuttled around the leaf surface

There are only six species of Lonchoptera on the British list, but again they are only identifiable by rearing through to adulthood. There's an old RES Key to the adults (KGV Smith, 1969) but the eternally amazing Mike Hackston updated the fifty year old key just last year. The link to his reworked key is here.

Melanostoma larva flip these delightful lonchopterids onto their back, stab down into the belly and suck out the body fluids. They also feed on Lauxaniid larvae, but I didn't knowingly see any of those. 

I did however see another dipteran larva that will happily predate Melanostoma (it's a fly eat fly world out there!) I owe this identification to Geoff Wilkinson on the UK Hoverflies Larval Group FB page

Phaonia sp (Muscidae) - a fierce predator and quite capable of killing the Melanostoma larva I found earlier

Once again it's a case of rearing it through to adulthood before being able to identify it to species. I didn't bring any larvae back with me, today. There's a very long way to go before it's springtime and they'd surely peg it if I tried to keep them alive.

So, my Diptera list remains at just one species for the year, but I really don't mind that. Today's enjoyment came through discovering all of these fly larvae, in all of their various guises, merrily doing their stuff, feeding, hunting and being hunted, all buried away from casual sight deep in the wet leaf litter. My little jolly through the woods has been a real eye-opener for me, it really has added a whole new dimension to my understanding and knowledge of the behaviour for some of the early stages of our fly families. It's not always just about pinning and keying, ticking and recording. Sometimes the bigger picture is far more colourful than expected. 

And craneflies have crazy faces on their arses - amazing!     

Amara, Amara, I love you Amara...

Ok, so it now appears that yesterday's beetle wasn't Amara aenea at all. Why not? Well because I fooked up, that's why. You can tell a lot by the comments that folks leave. I had two this morning, both pointing me towards an alternative key to Amara. Ha, that's never going to be a great confidence booster (though was muchly appreciated all the same!) Several hours later Mark Telfer cut to the chase and gently suggested I'd hashed up the ID. So I went back to it with a fresh set of eyes (and in daylight this time rather than by the light of an energy saver bulb) and guess what...it has a blatant hair sticking up from a scutellary pore on the right elytron! 

This tiny wee hair categorically rules out aenea. In fact, the presence of this hair takes us down an entirely different route through much of the keys. I psyched myself up, chickened out, psyched myself up once more, and immersed myself in the keys again. Rather tellingly the RES Key just happened to fall open on the page for Amara...

I was determined not to mess it up this time. I used to believe that if you had a specimen and a key you'd always get a correct result. Then I started using keys. The truth is that all too often you have to make a judgement call regards interpreting a feature, or the wording of a key. It's rarely completely black and white, lots of grey areas. And novices in particular flounder in grey areas. 

Anyway - so I took the keys to the beast for a second time. It's definitely Amara, that much seems agreed by all. So...

1) Apical spur of front tibia a single tooth (or) spur divided into three teeth?

Hmmm...not sure I like that arrow. I think I'll refrain from adding any more 'artistic extras' from now on

As can clearly be seen, this is a single-toothed rather than three-toothed spur. The small spines you can see in the background are nothing to do with this apical spur. Cool, first couplet done and no grey areas so far.

2) Antennae with one to three pale basal segments, remainder more or less abruptly dark (or) all uniformly pale brown

Categorically exhibits "pale basal segments with the remainder more or less abruptly darkened"

This takes us to Amara sensu stricto, so far this is the same route I followed yesterday.

New key, so let's start afresh.

1) Legs entirely pale (or) at least femora darkened, often dark brown or black

Well they definitely aren't entirely pale!

4) Third antennal segment entirely darkened (or) at least basal half of third antennal segment pale. Checking the middle image above, quite clearly the latter part of that couplet fits very well. 

8) Length less than 6mm. Scutellary striae absent. Scutellary pore absent (or) length at least 6mm. Scutellary striae present, sometimes also with a scutellary pore.

Well that's got to be a good 8mm or so

Scutellary striae present and correct. Apologies for the pin, clearly I was a complete barbarian back in 2017...

9) Scutellary pore present

BINGO!!! There bloody well IS a scutellary pore after all. This is where I went so wrong yesterday! 

So from this part of the key onwards I'm on fresh turf, hopefully leading me to a definitive ID.

10) Length more than 9.5mm. Apex of elytra strongly produced (or) length 9mm or less, elytral apices hardly produced

Bit misleading, because I harpooned it with a ruddy great pin, but I don't think these are "strongly produced"

Aside from the size options given, this was the first somewhat subjective part of the keying process so far. Probably be a lot easier if I had other specimens to compare it with. But I don't have the luxury of owning whole series of correctly identified specimens for each family. Not yet, anyway.

It didn't help that I'd driven a pin through the elytra in such a fashion as to splay the ends apart. But by comparing what I was looking at with the illustration in the key, and after checking a few online sites (skipping ahead to see what the species looked like were I to follow the "strongly produced" route) I satisfied myself that I was on the right track. Users of the RES Key will have by now noticed that I've cunningly managed to avoid all reference to fovea thus far. Yeah well, if there are other options available I'll gladly take 'em! 

11) Pore at hind angle of pronotum separated from side margin by c 2x or less its diameter (or) 3-4x

Awful, I know...sorry! But I reckon separated by less than twice its diameter. Certainly less than 3 or 4 times. 

12) base of pronotum not punctured. Tibia as dark as femora, usually black (or) base of pronotum at least partly punctured. Tibia often paler than femora.

Excruciatingly poor picture, I know -  but base of pronotum does appear to be entirely unpunctured

By scrolling back up the screen to earlier photo's in this post, we can see that the tibia are as dark as, rather than being paler than, the femora. At this point the key drops out at Amara ovata, a common species that has already recorded from Skye. I'm (quietly) confident that I have it right this time. Mark?

Carabids of Earlish

I took a wander out of my square today, just a couple of miles up the road to Earlish to see friends. Earlish is quite a bleak, barren place dominated by damp moorland or sheep pastures. The name translates as "place of strife" though I've yet to see signs of trouble up there. Anyway, I came across these stones which looked as good a beetling spot as any!

And no, I didn't check beneath the big white one

Instant success! First stone turned held this brute of a beast beneath, well that's definitely not Nebria brevicollis! 

Coming in at a whacking 17mm, just check those gorgeous red femora! 

This guy went straight into a tube. I scooped three smaller, all black carabids into a pot and headed back down to Uig. 

Three of the four specimens keyed straight to Pterostichus. First up, the Big Boy himself. 

1) Hind angles of pronotum rounded, not toothed (yep) - 2

2) apical (claw-bearing) segments of tarsi with setae beneath (sure do) - 3

3) third elytral interval with a single dorsal puncture, length at least 14mm, femora reddish or black - Pterostichus madidus

The features mentioned:

17mm in length

This 'red-thighed' version is known as P.madidus f. concinnus. The typical form has black legs.

The two remaining Pterostichus both keyed through to Pterostichus nigrita, which I've seen before up here and indeed, is a common beetle in this part of the world. I did err towards P.adstrictus for a while, I really do have issues when it comes to understanding the descriptions/diagrams of fovea, but by using several sets of literature plus some online sites I came true in the end. Helpfully, I have one that I prepared earlier, complete with nads splayed out on the card alongside the body, so I know it's a good ID. 

The last specimen was a Nebria. And it wasn't brevicollis! The quality of this next image will doubtless blow you away...

HAHAHAHAHAHAHAHAHAHAHAAAA!!!!!!

Anyway, the important thing is that through the microscope it was readily apparent that these hind tarsal segments were glabrous with not a single stray pale hair in sight. Which goes an awful long way to nailing Nebria salina. Then I checked the elytral microsculpturing and compared it side by side with a specimen of Nebria brevicollis - it's actually really quite noticeably different! For a start it shows up quite clearly at a low magnification whereas you need to zoom right in to brevicollis before its microsculpturing becomes apparent. Generally, salina looks greyer and scratched as opposed to the blacker, more shiny surface of brevicollis at similar low power. Nice! I've only knowingly seen salina up Mount Snowdon some years back (wasn't the nivalis I was hoping for...)

(L-R) Pterostichus nigrita female, P.nigrita male, P.madidus male & Nebria salina female

I'm quietly happy that I have these correctly identified. This morning I found that I'd received a couple of comments regards yesterday's Amara specimen - the one I wasn't particularly satisfied that I had correctly IDed. Clearly I wasn't the only one having doubts! Anyway, in the light of day I noticed a hair sticking up on the right elytron, following this hair to its base revealed a scutellary pore to be present - hence completely rubbishing my ID of Amara aenea! 

Tonight I logged on to find that none other than Mark Telfer himself has rubbished the A.aenea ID. Good news - this means I can go back and try it again (and hopefully come up with the same species as Mark suggests!) Give me thirty mins and I'll go try it again...I just need to psych myself up a bit first.

Bitter Keying

I spent much of today ripping up old carpets and underlay and checking beneath floorboards throughout the entire reception/lobby/bar area. Not a sniff of any beetles, bugs or flies. Not even a dead bluebottle. Hygiene levels are obviously set far too high in this hotel, dammit...

So I decided to have a trawl through the 'unidentified' section of my Skye storebox. Oooh look, some mystery beetles! Practice makes perfect (well, less awful) and all that. I grabbed a carabid that looked like an Amara to my untrained eye. 

Keying it through to family I was pleased to prove myself right, it was an Amara after all. Not an especially tricky family to recognise, to be fair. But a bit of an arse ache to get to species, by all accounts (not named Amara for nothing...) 

Undaunted, I hit the keys. Somehow I only went wrong a couple of times before everything slotted into place surprisingly well. 

Apologies for the pin, this was from way back in 2017!!!

Any thoughts yet? I'm sure some of you will have sussed it already, but I'm a numpty and don't know the shortcuts yet. Keying through went a little like this - 

So I'd already keyed to Amara and was happy with that. I then needed to check the apical spur (single rather than tri-lobed) and the antennae showed pale basal segments that abruptly changed to darker segments. That took me to Amara sensu stricto. Cool, I'm getting somewhere.

Running the key through all relevant couplets went as follows - 

1) Legs entirely pale (nope!)…..4

4) At least basal half of 3rd antennal segment pale (it was entirely pale, in fact)…..8

8) Length at least 6mm and scutellary stria present (definitely on both counts)…..9

9) Scutellary pore absent....14

14) complicated shizzle (deep breath...) 

So my blind spot has always been seeing the fovea. No, that's not right. I mean, I can see them, interpreting what I'm looking at is the issue I have. No matter how I angle the light source, or the beetle itself, I just cannot match what I'm seeing to the drawings in the keys. Ever. Which is a real pisser, because by this point I'd narrowed it down to just four species (and one of those doesn't occur in Scotland). 

So that just doesn't match anything for Amara! 

Seriously, I always fall down at this point. Crossed epipleurs not a problem. Dorsal punctures along the striae not a problem. Number of hairs on penultimate segments of labial palps, easy. Recurved striae fine. Fovea? Get lost!

So, back to 14)

14)  - elytral striae fine to elytral apex, where intervals are flat, inner pronotal fovea consisting of a short, deep streak
 - elytral striae deepened apically, where elytral intervals are convex, inner pronotal fovea shallow or more gradually defined

Oh bugger off. What kind of concrete features are those meant to be? Ok, so the intervals looked fairly flat but with possible convex curvature. And who even knows what the fovea looked like! These are subjective decisions to make, and the key requires a decisive yes or no to progress. I dunno, bit of both maybe? How flat? How deep? How fine? How short a streak? What classes as shallow in the world of fovea?

If I decided to plump for the former option it dropped me out to species. If.

If I decided the latter option worked best it led to a further three species. I continued onwards and it didn't work (pronotum wasn't punctured and elytral punctures weren't interrupted) which dropped out at a very rare species entirely unknown to Scotland. So, by backing up a little and choosing the former option the key drops out at a very common species which is already known from Skye.

Ok, former option it is then! Not an entirely satisfactory use of the keys, I have to admit. However, I did a lot of background reading regards the species it keyed through to. Everything looked fine but, as per usual, it was the fantastic Watford Coleoptera Group that provided the necessary confirmation.

First three and base of fourth antennal segment orange, seemingly a very good feature

The WCG add an awful lot of extra detail that isn't in the keys. Stuff like the edges of the pronotum being thickly bordered laterally but less so basally, that the basal pronotal setae is situated close to the hind corner which is almost right-angled, the presence of two preapical punctures on 7th striae and another at the tip of the 2nd striae. I checked my specimen, everything fitted beautifully. They also confirmed that it's a dirt common species.

So, after all that, what is it? Well, this is a male Amara aenea and a lifer for me. Nice, pity it took me nineteen whole months to get around to keying it through!

I have a bonus day off work tomorrow (we prepped everything for the builders in one day instead of the anticipated two) so I shall be out there again trying to find all things beetle, fly or bug orientated. Tune in later for more of the same!

Staphs and a Snail-eater

Today I spent an hour or so searching beneath logs, rocks and bits of debris for beetles. Mostly I was expecting to find the carabid Nebria brevicollis, a surprise absentee yesterday. Guess what...

Nebria brevicollis - it's a pretty common beetle up here

There are three species of Nebria that could occur up here in Uig, so I need to keep my wits about me and continue checking. I'd hate to think I'm overlooking Nebria salina and Nebria rufescens, both of which occur widely up here. Nebria nivalis is known from Skye too, though presumably only from high, barren mountaintops. Yep, I definitely need to keep scrutinising them all. 

The all important hind tarsi - has a double row of fine hairs in N.brevicollis which are absent in N.salina

So that was brevicollis added to the burgeoning list (3 species of beetle now, oof!) What else could I find? 

This is the finest pile of rocks for miles around!

I've gone through these dumped rocks so many times I've lost track. It's a great hunting ground for slugs, snails, millipedes, centipedes, flatworms, harvestmen, worms, woodlice, nemerteans - and beetles, of course!  

Large carabid in it's cell

I love lifting a rock and finding something like this! Abax and Cychrus make these 'overwintering cells' as I call them, I often find millipedes or slugs curled up inside vacant cells. I can only think that the big bulky beetles know they'd get flattened if a curious entomologist lowered their rock down too quickly, so it's clearly an adaptation to survive folks like me. Truly nature is marvellous.  

This carabid was covered in dirt, something I've come to realise means it's likely to be Cychrus rather than the shiny, clean Abax. A gentle bit of teasing out with a twig later and...

Oooh yeah, that's Cychrus caraboides alright! A female judging by the size of the maxillary palp tips

Those elongated jaws and the narrow head are adaptations to suit its feeding habits. This beetle preys on snails (the genus Oxychilus being favourites - plenty of those here) by jamming it's whole head into the shell. I bumped into Neil, a local chap who, amongst a great many other things, is quite into his beetles. He asked me why they don't feed on slugs too. I couldn't answer that, maybe slugs are too slimy, maybe they're too big and muscular, maybe they fight back! Or maybe it's because Oxychilus smell garlicky and taste better? I just don't know. 

Beneath the same pile of stones I found a rather handsome staphilinid, one I see quite often but haven't ever gotten around to keying through. Terrible behaviour, I do have the book after all. 

Back indoors I made a pretty poor job of the whole carding process. I'll soak it off the card, relax it properly and try again, see if I can't get it to lay a bit flatter and neater than it currently is. 

What a bodge job. Beautiful beetle though

Running it through the keys to genera it dropped out at Tribe Othiini, and then to the genus Othius. From there it was easy - bigger than 9mm (yep, it was 11mm) = Othius punctulatus. I'll refrain from mentioning the fact that I was going around in circles for about an hour, all because I misinterpreted what the key was asking me to check. Maybe I ought to find a grown up to sit beside me when I'm keying stuff from now on. Anyway, got there in the end! I've been shown Othius punctulatus before, but this is the first time I've keyed it for myself and thankfully it's distinctive enough that I can ID it by eye from now on. It's a common beetle which has already been recorded from Skye and Raasay.

You can read lots more about Othius punctulatus by clicking on this page

Back to work tomorrow, I'll do my best to try and find something to blog about though. 

Ptinus fur - new for Skye

Well it appears that I was right, last night's beetle is indeed Ptinus fur, a lifer for me and seemingly new to the Inner Hebrides (Moore, 2012).

There are several species in the genus, some of which look quite similar. Add to this the variability in elytral patterning and overall shape differences between the two sexes and it could be quite easy to misidentify this small beetle. Thankfully the family is covered by Joy and Mike Hackston has provided one of his fantastic online keys which covers the Ptinidae. By bumbling my way around these I narrowed it down to species. 

Some pics of the beast

Pronotum with two combs of longer, thickened hairs which are very pale whitish-yellow and directed backwards forming an angle with one another in the middle of the constriction at the base (Hackston)

Evenly rounded shoulders so presumably a female

4th abdominal segment less than half the width of the 3rd

I'm really going to have to find a setting that has a better white balance to it. Or maybe use a different lighting set up for my microscope.

A quick bumble through the woods added a solitary Phosphuga (Silpha) atrata to the Beetle Yearlist which now stands at a huge two species. Rather shockingly, no sign of Nebria brevicollis!

This afternoon I shall attempt to card the Ptinus, it'll be the smallest thing I've ever carded by a mile! Wish me luck...

Update: carding was duly undertaken, I'm not sure where my fine paintbrush has disappeared to so I had to use pins to move bits into place. Not ideal! Anyway, here she is