When details matter: Integrative revision of Holarctic Coelophthinia Edwards (Diptera, Mycetophilidae), including mapping of its mitogenome, leads to the description of four new pseudocryptic species.

Background: The small genus Coelophthinia Edwards, 1941 of the subfamily Gnoristinae (Diptera, Mycetophilidae) is so far known to harbour four species from the Palaearctic, Nearctic and Neotropical Regions. Extensive DNA barcoding of fungus gnats of the family Mycetophilidae through the International Barcode of Life project (iBOL) have initiated integrative studies resulting in taxonomic upgrades and a better understanding of many species and their delimitation. The opportunity was also taken to describe the mitogenome of a member of Coelophthinia for the first time.

New information: The integrative studies give evidence for splitting the European species C.thoracica Edwards, 1941 into three different species. Four new species are described from the USA, Japan and the Nordic Region in Europe, Coelophthiniacirra Kerr sp. n., Coelophthiniaitoae Kurina sp. n., Coelophthinialata Kjaerandsen sp. n. and Coelophthinialoraasi Kjaerandsen sp. n., raising the number of Holarctic species from two to six. The mitogenome of Coelophthinialoraasi sp. n. is described and analysed.