Flea beetle

Shook some grass out onto the back of the sweep net yesterday and caught a bevy of small beetles. Amongst them was a group of shiny blue-ish beetles which caught my eye as leaf beetles - a target area for the year. I potted them and hoped for the best.

It was relatively straightforward to confirm them as leaf beetles, and to narrow it down to a group called flea beetles - you can see the hind leg are made for jumping, and the explosive way they occasionally cannoned around inside the pot was remarkable

Here's where it gets tricky. The genus they belonged to was Altica, comprising a handful of very similar species, which really require dissection of males to finally determine.I may consider doing this later, but I'm not up for beetle dissection yet and I don't really have the tools. I had a crack at the key and atlas anyway - you never know.

Working from the total list ...

Altica longicollis (= Altica ericeti) - possible candidate
A.olaracea - lacks diagnostic elytral markings
A.lythri - too southerly in distribution
A.helianthemi - too southerly in distribution
A.brevicollis - too southerly in distribution
A.palustirs - scattered records, possible candidate
A.carinthiaca - too southerly in distribution

This gives us basically two realistic candidates, and one of them keys out at the first step - A.longicollis has straight edge elytae for 2/3 of length. Does this? Maybe! I haven't completely given up on going all the way, but for the moment it will have to go down as Altica sp.