This is one of our most abundant and widespread species. It is in all the lists, even appearing at coastal sites, contradicting Robson's contention that it did not appear in this kind of habitat. Sometimes in such large numbers that wingless females have appeared in the trap still in cop with the males and since these can have been only a very small percentage of the individuals at any one time, the potential count must be enormous. The appearance of females in traps also explains the often debated point as to how species with apterous females can spread and so increase their range of distribution. Variation in the males is considerable and a large number of different forms are known.