Woodland Earwig Male

Chelidurella guentheri is an earwig belonging to the family Forficulidae.

This species has very reduced wings, only recognizable as a narrow arched band over the mesothorax. Males cerci are horizontally arched almost into a circle shape and carry only a fine tooth above. Female cerci are not modified. The head usually is of a bright orangy tinge.

Please note that nymphs of various winged species are often misidentified as this species due to the fact that those nymphs do not carry recognizable wings either (yet). On those however the shape and structure of the meso- and metathorax is different, as well as the number of antennal segments (if undamaged).

The Woodland Earwig is historically recorded all over Europe as Chelidurella acanthopygia but in the last decades of the twentieth century it was split up into many species with more limited ranges (Harz 1980, Capra 1982, Vigna Taglianti 1993, Galvagni 1994, 1995 & 1996). For the animals found in the northwest European lowlands Antonio Galvagni (1994) split off a new species by the name of Chelidurella guentheri, mostly based on the shape of the male pygidium but at the same time also documents a wide variability in this character.
Most modern taxonomy databases follow this, as it is taken to be the last taxonomic scrutiny, but at least Albouy & Savourey (2001) have published severe criticism (Vincent Albouy being one of Europe's foremost earwig researchers) stating that there is too much individual variability in the criteria used by Galvagni to identify his species and that going by his criteria they would have to identify various individuals from one population in France all taken on the same day at the same location into three different species sensu Galvagni and other authors.
Nevertheless the currently widely accepted practice in naming these still seems to be in favour of Galvagni, so here at JD we should probably follow that. This specimen from the Netherlands would hence be Chelidurella guentheri, not Chelidurella acanthopygia.

Albouy, Vincent; Savourey, Michel (2001) Dermaptères (Perces-oreilles) des Alpes du nord en France in La Saga, Vol.4, pp.5-9.
http://miramella.free.fr/doc/SAGA04.pdf

Galvagni, A. (1994) Chelidurella guentheri specie nuova dell'Europa centrale e della Norvegia Sud-orientale (Insecta Dermaptera Forficulidae). - Atti Accad. Rov. Agiati, Cl.Sci.Mat.Fis. Natur: Ser.7, Vol.3B(243), pp.347-370.
http://www.museocivico.rovereto.tn.it/UploadDocs/6741_A_Galvagni_p_347.pdf