Genus Ethelurgus Förster, 1869

Tolmerus Förster, 1869: 177 . Type: Phygadeuon sodalis Taschenberg, 1865 . Designated by Townes & Townes (1966).

Ethelurgus Förster, 1869: 180 . Type: Hemiteles (Ethelurgus) lonicerae Viereck, 1917 (= Hemiteles syrphicola Ashmead, 1890). Included by Viereck (1917).

Nuneches Förster, 1869: 186 . Type: Phygadeuon sodalis Taschenberg, 1865 . Designated by Perkins (1962).

Platycryptus Kriechbaumer, 1893: 150 . Type: Phygadeuon sodalis Taschenberg, 1865 . Designated by Horstmann (1992).

Zamicrotoridea Viereck, 1917: 340. Type: Hemiteles (Zamicrotoridea) orbiformis Viereck, 1917 (= Hemiteles syrphicola Ashmead, 1890). Monobasic.

Four species, E. episyrphicola Kusigemati, 1983, E. kumatai Kusigemati, 1983, E. sodalis fuscipes Townes, 1983, and E. politus Townes, 1983, have been recorded from Japan. Kusigemati (1983) and Townes (1983) individually revised Japanese species. I compared the types of these species deposited in AEIC and SEHU and conclude that E. episyrphicola and E. politus, and E. kumatai and E. sodalis fuscipes are same species, respectively. Townes (1983) was published in December and Kusigemati (1983) was published in March. Thus, I newly synonymize E. politus under E. episyrphicola and E. sodalis fuscipes under E. kumatai . In addition, according to Horstmann (2000), the taxonomic status of E. kumatai should be treated as subspecies of E. sodalis (Taschenberg, 1865) . Thus, I treat that E. kumatai is as the subgenus of this species (comb. nov.). In addition, I recognize an undetermined species from Japan, while the identification of this species requires more materials. Japanese species can be distinguished by the following key.

Preliminary key to Japanese species of the genus Ethelurgus (♀)

1. Mesoscutum polished (Fig. 30C). A smooth area of mesopleuron distinctly larger than speculum (Fig. 30D). Coxae and femora more or less tinged with reddish brown (Fig. 30A). .................................... E. episyrphicola Kusigemati, 1983 (= E. politus Townes, 1983 syn. nov.)

-. Mesoscutum matt (Fig. 31C). A smooth area of mesopleuron larger than or as size as speculum (Fig. 31D). Coxae and femora black (Fig. 31A). ............................................................................................ 2

2. Mesopleuron covered with longitudinal striae except for speculum (Fig. 31D). T II covered with longitudinal striae basally (Fig. 31C). ................................. E. sodalis kumatai Kusigemati, 1983 (= E. sodalis fuscipes Townes, 1983 syn. nov.)

-. Mesopleuron punctate and smooth dorsally, longitudinally striae ventrally. T II without longitudinal striae. ..................................................................................... E. sp.