bugboy wrote: ↑Fri Aug 02, 2024 1:52 pm
it's the front of the nudum, not the underside tip…
The distal antennomeres?
Looks like in practice it is something that in the field is indistinguishable. I think knowing the scientific name and exact location of these coloured cells doesn’t really help to tell the difference between Essex & Small Skipper for me. Under a microscope it may be different but that is not something butterfly recorders carry out.
I wondered if the combination of identification features provides much better chances of distinguishing the two?
Obviously the challenge is predominantly the female, when the Small Skipper has the above feature provided by Pete - that is looking from the front, slightly below the antennael tip level and cannot see orange at the tip, when she also has similar features which we mostly would associate with the Essex, such as black edges bleeding into the veins.
Especially, which I mentioned in my latest PD post, at the end of the season when they are both worn and tatty.
I was actually wondering whether the distal antennomeres can also appear faded to the extent the ink black of the Essex Skipper can take on a dark brown at certain angles to the light?
Anyway, very difficult, and not something, I think, we can leave to a set of “rules” or whatever as also mentioned above.
Interesting topic - I wish I knew the answer so that I was 100% confident in my identification rather than making informed assumptions about what it probably is based on such things as density/percentage colony combination. Or does it matter because we are probably talking about one or two only in a colony of 30-50?