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?