Checklist of the familes Chaoboridae, Dixidae, Thaumaleidae, Psychodidae and Ptychopteridae (Diptera) of Finland

Abstract A checklist of the families Chaoboridae, Dixidae, Thaumaleidae, Psychodidae and Ptychopteridae (Diptera) recorded from Finland is given. Four species, Dixella dyari Garret, 1924 (Dixidae), Threticus tridactilis (Kincaid, 1899), Panimerus albifacies (Tonnoir, 1919) and Panimerus przhiboroi Wagner, 2005 (Psychodidae) are reported for the first time from Finland.


Introduction
Psychodidae or moth flies are an intermediately diverse family of nematocerous flies, comprising over 3000 species world-wide ). Its taxonomy is still very unstable, and multiple conflicting classifications exist (Duckhouse 1987, Vaillant 1990, Ježek and van Harten 2005. The nomenclature used in the Finnish check-list follows the Norwegian one (Kvifte et al. 2011). For differences between the taxonomy used herein and that used in previous works on Finnish Psychodidae (e.g. Hackman 1980, Salmela 2003, 2005, Salmela et al. 2007, Autio and Salmela 2010 see Kvifte et al. (2011). Two species, Pneumia nubila and Pneumia palustris, listed in the previous check-lists by Hackman (1980) and Wagner (2013) have not been confirmed through study of material. Of these, P. palustris have been suggested to be synonymous with Pneumia gracilis (Eaton, 1893) (Withers 1989). Both these species have been linked to some taxonomic confusion in the past, and thus the record of P. nubila may represent Pneumia trivialis. The present check-list contains the first Finnish records of the species Threticus tridactilis (Kincaid, 1899), Panimerus albifacies (Tonnoir, 1919) and P. przhiboroi Wagner, 2005 (see Notes).
Finnish Psychodidae are very well studied compared to other Nordic countries, however new species are still being discovered at a regular rate. Most of these are new country records, but in recent years the fauna has also yielded some species new to science (Salmela et al. 2012, Kvifte unpubl.). This trend is likely to continue. Probably between twelve and thirty further species can be expected to be found in the Finnish fauna. There are no good identification sources available for Psychodids, as all works suffer from taxonomic or nomenclatural errors and/or insufficient descriptions. The best works relevant to the Finnish fauna are Vaillant (1971Vaillant ( -1983, Withers (1989) and Wagner (1997c, genera only).
Phantom midges (Chaoboridae) are close relatives to mosquitoes (Culicidae) and meniscus midges (Dixidae) (Saether 1970(Saether , 1997. There are around 50 known species of phantom midges in the world and 15 in the palearctic region, of which five are holoarctic species. In Finland, there are eight species in three genera (Hirvenoja 1960, Hackman 1980, in which the species in the genus Mochlonyx were still doubtful).
The only strictly lacustrine species in Finland is Chaoborus flavicans. The other species live in small fishless lakes, ponds and springs where their predators are mainly dragon flies, dytiscid beetles and frogs. Chaoborus nyblaei and Cryophila lapponica are found from small fishless ponds on fells and ponds created by melting water. However, in 2013 larvae of C. nyblaei were found from the boreal zone, NE Lapland (Savukoski) from a small but permanent pond. Chaoborus pallidus lives in eutrophic lakes and small lakes in southern and central Finland (Hirvenoja 1960, 1963, Paasivirta 2002. However, there have not been any systematic surveys of the fauna across the biogeographic provinces and the conservation statuses of the species have not been evaluated. Finnish species can be identified by using Saether (1997Saether ( , 2002. Meniscus midges (Dixidae) belong to infraorder Culicomorpha. There are nearly 200 known species of which 53 occur in the Palaearctic region. In Finland two genera and 16 species are present (Hackman 1980, Salmela 2003, Salmela et al. 2007). One species (Dixella dyari Garret, 1924) is reported here for the first time from Finland (see Notes). Larvae of meniscus midges dwell in or slightly above water meniscus, having a characteristic U-shaped position (Wagner 1997a). Members of the genus Dixella are associated with lentic or slow flowing waters, such as ponds, lake shores and bog pools. Species of the genus Dixa are lotic, dwelling in running waters of varying size. Two Finnish species, Dixa dilatata and D. submaculata prefer springs and spring brooks. The Finnish fauna is generally rather well known, although three species have hitherto been collected from single localities. One northern Dixa species close to D. dilatata is still undescribed. A majority of the species can be identified by using Martini (1928), Peus (1934Peus ( , 1936, Vaillant (1967) and Disney (1999).
Trickle midges (Thaumaleidae) is a small family belonging to infraorder Culicomorpha. Globally, nearly 200 species are known of which 76 are European. Central European mountains harbor a rich assemblage of trickle midges (Wagner 2002), at least if compared to the poor diversity (5 spp.) in Fennoscandian area (Wagner 1997b, Andersen et al. 2013. Only one species, Thaumalea truncata, has been hitherto recorded from Finland (see the discussion in Andersen et al. 2013). Larvae of trickle midges dwell on hygropetric substrates or splash zones of running waters (Wagner 1997b). Thaumalea truncata occurs mainly in northern Finland, both boreal and subarctic ecoregions, and adult specimens have been caught around springs and headwater streams (Salmela 2003, Salmela 2008. Phantom crane flies (Ptychopteridae) belong to infraorder Ptychopteromorpha, being a sister group of Psychdomorpha and Culicomorpha (Wiegmann et al. 2011).