Ripping off the Olive Branch

Yesterday I nipped into one of our garden centers in south Leics. Whilst mooching about with Nichola, I noticed some olive trees and had a moment of de ja vu. I looked them over and sure enough found clear evidence of larval feeding with spinnings and frass. It was then that I remembered that I'd seen the same feeding damage in the same place last year and completely forgot to follow up in any way. When I got home, a quick check online and a browse through photos on my phone and I got a bit closer.

Here's a snap from yesterday:

Larval feeding signs on Olive Tree (Olea europaea)

This feeding damage was actually quite high up on a well established (and very expensive) tree. There was no way I could serruptitiously rip off the olive branch. At least not on this visit! The older photos I found were from 14/07/2018. These were on smaller and more accessible plants, but given that I wasn't sure what to look for I didn't acquire any samples. Here's a selection:

I'm absolutely convinced that this feeding damage is lepidopteran. There's really not much that is likely to be feeding on olive in this country, and the two prime contenders are both adventive species recently added to the UK list. Neither has been recorded in VC55: Prays oleae (new to UK in 2009) and Zelleria oleastrella (new to UK in 2006). There is a chance that it could be from a native polyphageous species, but what is more likely!

Either way, I am now better clued up on olive-feeding species and will be watching this place over the coming weeks to nail the ID.

Earlier in the week I had another look at local Holm Oaks, with the specific aim of finding mines of Stigmella suberivora. I found some, all vacated, on a couple of trees:

This leaf has a vacated S. suberivora mine, and two tenanted Ectoedemia heringella mines. They are similar except that the heringella mines are more convoluted at the start and around half the size (this E. heringella mine is about finished).

What I also found was that of three trees checked, one was so heavily infested with E. heringella that it was hard to find anything else at all and there were barely any 'clear' leaves. Another was infested but no quite so heavily, and there were S. suberivora mines including the one above. The third tree appeared completely clear of E. heringella, with S. suberivora mines evident. But, the clear tree is virtually in the middle of the other two:

Tree A heavily infested, tree B clear, tree C infested. Doubtfully any Holm Oak inbetween.

Here's a couple from the garden last night to close:

Early Grey - 15/03/2019

Small Quaker - 15/03/2019