Tachys Dejean, 1821

Bousquet, Yves, 2012, Catalogue of Geadephaga (Coleoptera, Adephaga) of America, north of Mexico, ZooKeys 245, pp. 1-1722 : 447-448

Genus Tachys Dejean, 1821

Tachys Dejean, 1821: 16. Type species: Tachys scutellaris Stephens, 1828 designated by Hope (1838: 61) (see ICZN 1990). Etymology. From the Greek tachys (swift, quick, fast), probably alluding to the quickness of the adults in the field [masculine]. The name was proposed by Franz Anton Ziegler and made available by Dejean.

Diversity.

Worldwide, with about 180 species (Lorenz 2005: 212-214, as Paratachys and Tachys ) arrayed in two subgenera, both represented in North America.

Nomenclatural Note.

The first use of the name Tachys is by Schönherr (1806: 221) who included 23 species-group taxa under it. Ádám (1996: 11) selected Carabus quadriguttatus Fabricius, 1775 (= Cicindela quadrimaculata Linnaeus, 1760), one of the species originally included, as type species of Tachys Schönherr, 1806. This action implies that Tachys Dejean, 1821 is a junior homonym of Tachys Schönherr, 1806 which is a junior objective synonym of Bembidion Latreille, 1802. Obviously, to preserve nomenclatural stability, the name Tachys Schönherr, 1806 should be rejected.

Taxonomic Note.

Shilenkov (2002) treated Tachys and Paratachys as distinct genera, pointing out four major structural differences between the two taxa. Sciaky and Vigna Taglianti (2003) took the same approach. In view of the large concept used here for the genus Elaphropus , I believe it is more appropriate to retain the two taxa as subgenera of Tachys , following in this sense Kopecký (2003: 275-277) and Lorenz (2005: 212-214). Sciaky and Vigna Taglianti (2003: 82) suggested that Polyderis is closely related to Tachys and Paratachys based on the presence of labial pits.