Clusiidae Handlirsch, 1884

Jindřich Roháček

Department of Entomology, Silesian Museum, Tyršova 1, CZ-746 01 Opava, Czech Republic; rohacek@szmo.cz

Small to medium-sized (2.0-8.0 mm), slender, blackish-brown to yellow flies. Wing usually partly darkened or patterned; legs yellow or variably darkened, face, gena and legs sometimes sexually dichroic. Head broader than long, usually with strong cephalic bristles, most of the orbitals usually reclinate, vibrissa long and robust. The family forms the most generalised group of the Opomyzoidea, retaining a number of plesiomorphic features (arista more or less apical, most complete cephalic chaetotaxy and ving venation, C with an indistinct break at apex of Sc that is widely separated from R1) and a few apomorphic characters such as pedicel with a sharp angular lobe on external distal margin, postverticals situated very close together and prosternum setulose.

Clusiidae are typical inhabitants of forests with a rich supply of dead tree wood. The xylosaprophagous larvae develop in the decayed wood of fallen trunks and stumps, pupariate inside the rotten wood and overwinter in the pupal stage. The adult flies can best be observed sitting or walking on dead tree trunks; they fly away only when disturbed but soon return to the same or the nearest convenient log.

Fourteen species have been recorded in Europe (Roháček & Merz 2004); 11 of them are listed in the present checklist (11 in the Czech Republic, 11 in Bohemia, 10 in Moravia, and 9 in Slovakia). Since the last version of checklist, the number of species in the Czech Republic has increased by 1 (3 in Bohemia, 0 in Moravia); no species has been added for Slovakia. The Clusiidae are relatively well known in the Czech Republic but slightly less so in Slovakia. The family was characterised in detail by Sasakawa (1998) who also gave a key to Palaearctic genera. There is no recent literature for the identification of all the European species; however, they can be identified using the keys compiled by Stackelberg (1970), Soós (1981) and Stubbs (1982). The species occurring in the Czech Republic and Slovakia have been treated faunistically by Roháček (1995), including all the previously published data; for papers published subsequently, see Roháček and Barták (2000). The nomenclature corresponds with that in the Fauna Europaea (Roháček & Merz 2004), with the subfamily classification recently proposed by Lonsdale and Marshall (2006).

References

[1] Caloren D.C. & Marshall S.A. 1998: A revision of the New World species of Clusiodes Coquillett (Diptera: Clusiidae). Studia dipterologica 5: 261-321.

[2] Lonsdale O. & Marshall S.A. 2006: Redefinition of the Clusiinae and Clusiodinae, description of the new subfamily Sobarocephalinae, revision of the genus Chaetoclusia and a description of Procerosoma gen.n. (Diptera: Clusiidae). European Journal of Entomology 103: 163-182.

[3] Roháček J. 1995: Clusiidae (Diptera) of the Czech and Slovak Republics: faunistics and notes on biology and behaviour. Časopis Slezského zemského muzea, Opava (A) 44: 123-140.

[4] Roháček J. & Barták M. 2000: Some families of Diptera Acalyptrata of six peat-bogs in the Šumava Mts. (SW Bohemia, Czech Republic). Časopis Slezského zemského Muzea, Opava (A) 48 (1999): 125-151.

[5] Roháček J. & Barták M. 2001: Clusiidae. In Barták M. & Vaňhara J. (eds): Diptera in an industrially affected region (north-western Bohemia, Bílina and Duchcov environs), II. Folia Facultatis Scientiarum Naturalium Universitatis Masarykianae Brunensis, Biologia 105: 337-340.

[6] Roháček J. & Merz B. 2004: Fauna Europaea: Clusiidae. In Pape T. (ed.): Fauna Europaea: Diptera, Brachycera. Fauna Europaea version 1.1, http://www.faunaeur.org.

[7] Sasakawa M. 1998: 3.16. Family Clusiidae. In Papp L. & Darvas B. (eds): Contributions to a Manual of Palaearctic Diptera. Vol. 3., Higher Brachycera. Science Herald, Budapest, pp. 219-225.

[8] Soós Á. 1981: Clusiidae - Fatönlegyek. Fauna Hungariae, 149. Akadémiai Kiadó, Budapest, pp. 93-108.

[9] Stackelberg A.A. 1970: Clusiidae. In Bey-Bienko G.J. (ed.): [A key to the identification of insects of the European part of the USSR]. Vol. 5(2). Nauka, Leningrad, pp. 303-305. (In Russian).

[10] Stubbs A.E. 1982: An identification guide to the British Clusiidae. Proceedings and Transanctions of the British Entomological and Natural History Society 15: 89-93.