help with unusual caterpillar please .

[Allan.W.]

I wonder if some of you good people would cast an eye over this unusual green twig like caterpillar that a workmate found on his wall a couple of days back Please ,i,ve looked through all the possibles ,and in various books including the excellent field guide to caterpillars of GB and Ireland and i must admit i,m stumped ! i reckon its about 30mm (ish) in length ...................any help ,much appreciated !

Regards Allan.W.

[bugboy]

I'd go with Brimstone Moth. It's the only chunky Geometrid larvae I can think of with that lump in the middle of the back and it does come in both brown and green forms

[Allan.W.]

Thanks for that Bugboy ! that one was on my "shortlist " and as you say it has the central hump like the Brimstone moth caterpillar,thanks for the help . Regards Allan.W.