I always seem to be contradicting Gruditch, but I promise it's not deliberate...
For my money (Swiss Francs), the skipper is
lineola (Essex) and I say this not just because of the antennae, which are notoriously deceptive from above, but because it is a male and it has a short, straight sex brand.
Guy
PS - Yes, welcome to the forum, Nick - full agreement with G on that!