Male dimorphism in the European earwig (Forficula auricularia) from woodlands and grasslands in a middle-Russian city (Kaluga, Russia)
Males of the European earwig, Forficula auricularia, are dimorphic in forceps length. Long-forceped (macrolabic) and short-forceped (brachylabic) males are considered as alternative reproductive tactics.Above 1500 specimens were collected with pitfall traps and shelters from 26 samples in Kaluga and surroundings, about 200 km southwest from Moscow, in the north of Middle-Russian Upland. About 46 % of specimens were macrolabic in total. Brachylabic males prevailed in woodlands, macrolabic males prevailed in grasslands. Gardens had intermediate proportion of long-forceped specimens. There were no significant differences between earwigs collected in various patches of habitats. There was no obvious seasonal dynamics of forceps length. Forceps length distribution was stable a year to year in the most of plots. In some habitats samples earwigs from pitfall traps were compared with samples from shelters in tree crowns.