Brown Native Earwig
S4, dorsal
Brown Native Earwig
S3, profile
Brown Native Earwig (Labidura riparia)Class: Animals (Animalia) - Jointed Legs (Arthropoda) - Insects (Insecta)
Order: Earwigs (Dermaptera)
Family: Striped Earwig (Labiduridae)     iNaturalist Observation
Species: Brown Native Earwig (Labidura riparia)
This Photo:     🔍S2, profile🔎
Synonym: Labidura truncata

Thank you Matthew Connors & Stephan Kleinfelder for confirming the id of this species for us

General Species Information:
Found on Ellura (in the Murray Mallee, SA) and elsewhere
~17mm long, pincers ~5mm long.
S1, S2 & S3 = female, S4 = male.
S3 was larger at 19mm, but doesn't have any visible wings behind the elytra; neither does S4. Stephen said "some individuals develop hind wings and some don't." A similar situation occurs with grasshoppers.
These have a very distinctive orange "V" on the thorax; and a very parallel sided abdomen.
Males are differentiated by have a spur on the inside edge of their pincers (cerci), and the join of the pincers to the body is noticibly thicker.
S1 & S2 came to a night light sheet.
The taxon associated with these is a mess. Mark Hura said "The taxonomy is interesting on this one - only Labidura riparia (Pallas, 1773) recognised in Australia on AFD with no fewer than 44 synonyms! :-/ BioLib lists 7 species worldwide, but looks like only L. riparia from Aust". And followed up with "Weird - L. truncata was resurrected from synonymy by Giles & Webb, 1972. Revalidated by Stuart et al 2019, although they acknowledge not all authors accept it as valid. McLean & Horridge, 1977 list it as L. riparia truncata just to confuse the situation even more!". Matthew said "I'm pretty sure the accepted name is still L. truncata, it's just that not all databases have updated with the new name for some reason. I think Dermaptera Species File missed one paper and then everyone else has copied them".
As we use Atlas (AFD) as our reference database (which currently considers them synonyms) we'll keep using Labidura riparia, with L. truncata as a synonym. We aren't making any opinions about which is right or wrong.
Photographed 4 in Feb & Mar.

Copyright © 2021-2023 Brett & Marie Smith. All Rights Reserved. Photographed 21-Mar-2021
This species is an Australian Native Species, not listed in the SA Murray Mallee Survey of 2010.