Thursday, 4 August 2022

'home grown' drurella!

Early July and a typical afternoon at the allotment. Typical being Mrs K doing all the graft and me with best intentions but getting distracted at every turn by insects. Our allotment is in the village and basically part of Litcham Common, so there is ALWAYS plenty to look at...and distract me.

So packing up after an afternoons allotmenting (and invertebrate based procrastination), I notice a few leafmines on some small Fat Hen plants coming through. I'm not completely rubbish with leafmines but I do need to take a bit of time and work them out but we were leaving so I left them be and headed home. Curiosity got the better of me and it wasn't long before I was looking at the species possibilities on that particular foodplant. Didn't take long to realise I'd found the mines of Chrysoesthis drurella and a couple of vacated mines, of it's close relative, Chrysoesthia sexguttella. Thanks as always, to Rob Edmunds (@leafminerman on Twitter) for confirming.

Chrysoesthia drurella

Chrysoesthia sexguttella (vacated)
 

I'd never seen drurella before but it's an absolute stunner of a Moth and - at only c5-6mm in length - hiding almost in plain sight. I couldn't let this oportunity pass. I used to rear quite of species through from eggs or larvae to adult but I seem to find myself with less and less time and so only rarely do so now. This beauty warranted the effort so I dashed back to the allotment, soaked to the bone within 5mins as the heaven's had opened since we left but found a couple more plants with at least half a dozen mines between them, so they came home with me.

Plants safely potted into some leftover compost, in a small bucket and placed in a netted enclosure. Done. Sadly, and probably annoyingly to my good wife, that was the most gardening I'd done all day! :)

Then the waiting game... plants stayed fresh and actually took really well, now growing against the top of the enclosure. An occasional spray of water to keep the soil soft enough for any potential borrowing larvae. 

I think it was more like 10 mines on these in the end.

now sit and wait...

During random checks I was lucky enough to see a single larva of drurella, wandering around the enclosure. Even the larvae are pretty!





With a little persuading, I coaxed it back to the soil where it started to get digging. I'd now seen the mines and the larvae and really hoping to get the hat-trick with an adult. Fast forward to last week and it's time for another water spray. I always inspect first, incase any sparkling fresh drurella have emerged and it SEEMED safe to open this time but clearly, I hadn't seen the small Moth on the underside of a leaf! As I unzipped the top - woosh! Little Moth flew straight out and passed my head. I couldn't even tell what it was. Gutted!!

Over the next few days, determined not to make the same mistake again, I saw that my drurella larvae didn't have the place to themselves after all. A small, parasitic Wasp of some sort had also emerged (potentially not boading well for one of the drurella larvae), followed two days later by 4x tiny bugs. These were Piesma maculatum, another Fat Hen feeder. New for me and not a bad record, but not a drurella!

Parasitic Wasp sp.

Parasitic Wasp sp.

Parasitic Wasp sp.

 

Showing the indented pronotum margins diagnostic to Piesma maculatum. That and having come from the correct foodplant.

Piesma maculatum

Piesma maculatum

Yesterday. Almost one month exactly after finding the mines - bingo! Cast your eyes upon a freshly emerged, Chrysoesthia drurella:

Chrysoesthia drurella

Chrysoesthia drurella

Well worth the effort if you ask me! With up to possibly 8-9 more larvae still under the soil, I could get to relive this again in the coming weeks. I Hope so!