Posted by Iain MacGowan on 28-08-2014 14:48
#4
Hi Bart
yes I agree with Paul they could be
Silba fumosa - this species is well known as breeding in decaying hogweed roots and stems so they could well have just emerged - but given most are females and look a bit gravid they could be congregating at a particullarly good oviposition site
Iain http://lonchaeidae.myspecies.info/