Dolichopus plumipes ( Scopoli, 1763 )

Kahanpää, Jere, 2008, Nematode-induced demasculinisation of Dolichopus males (Diptera: Dolichopodidae), Zootaxa 1689, pp. 51-62 : 59-60

Dolichopus plumipes ( Scopoli, 1763)

Musca plumipes Scopoli, 1763: 334

Dolichopus parvicaudatus Zetterstedt, 1843: 554 syn. nov. Dolichopus pectinitarsis Stenhammar, 1851: 130 syn. nov.

Demasculinised males examined: MZH — Finland, 1ɗ Eriksberg, E. J. Bonsdorff; 1ɗ Ab: Korpo, Jurmo, 6.viii.1960, M. Meinander; 1ɗ Ab: Turku, 9.vii.1954, E. Thuneberg; 1ɗ Lapponia, J. Sahlberg, id '1218.'; 1ɗ Muonio, R. Frey, id 3308. Russia, 2ɗ Trifona, W. Hellén, id 918 & 954; 1ɗ Archangelsk, R. Frey, id 3885; 1ɗ Vuoremi, W. Hellén, id 666; 1ɗ Gavrilova, R. Frey, id 5610.

Dolichopus parvicaudatus was described from from central Sweden ( Stenhammar 1851). It belongs to the D. plumipes group of species. The type material is now apparently destroyed ( Grichanov 2006b). The diagnostic characters separating this species are a very small hypopygium, a broad face, and mid tibia and tarsus without the secondary sexual characters of D. plumipes . D. parvicaudatus has been recorded from several countries in Northern and Central Europe ( Negrobov 1991).

Dolichopus pectinitarsis was described by Stenhammar from material collected from central Sweden. The type material is now apparently destroyed ( Grichanov 2006b). D. pectinitarsis is an intermediate between the strongly demasculinised D. parvicaudatus and normal specimens of D. plumipes . The male genitalia are small but not quite as small as in D. parvicaudatus . The mid tibia is narrowed as in D. plumipes but the dark dorsal stripe is absent. The mid basitarsus has two rows of flattened setae but they are much shorter and weaker than in D. plumipes . D. pectinitarsis has been recorded from several countries is northern and central Europe and also from northern Siberia ( Negrobov 1991). Wahlgren (1912) and Ringdahl (1949) classified both species as gynandromorphic forms of D. plumipes , but Parent (1938), Negrobov (1991), Grichanov (2004) and Yang et al. (2006) treat both D. parvicaudatus and D. pectinitarsis as valid species. Grichanov (2002, 2006b) has also expressed his doubt about the validity of these species.

All examined specimens (10 exx) of D. parvicaudatus and D. pectinitarsis were parasitised. The Finnish material nominally belonging to these species form a continuum from D. pectinitarsis - type males with normal genitalia to D. parvicaudatus , an extreme form caused by the presence of two or more parasites in a single host. The synonymy of Dolichopus pectinitarsis Stenhammar, 1851 with D. plumipes ( Scopoli, 1763) is here confirmed. Dolichopus parvicaudatus Zetterstedt, 1843 is also synonymised with D. plumipes .