Chthonius orthodactylus (Leach, 1817)

Obisium orthodactylum Leach, 1817: 51 .

Chthonius orthodactylus: Tömösváry 1882a: 239–240; Daday 1889a: 135; Daday 1889b: 25; Daday 1918: 2; Szalay 1968: 35–36; Kárpáthegyi 2007: 82; Červená et al. 2020a: 221; WAC 2023.

Chthonius (Chthonius) orthodactylus: Harvey 1991: 157; Christophoryová et al. 2011b: 36; Harvey 2013.

Occurrence: Austria, Belgium, Bosnia, Bulgaria, Croatia, Czech Republic, France, Germany, Greece, Hungary, Ireland, Italy, Luxembourg, Montenegro, Netherlands, Romania, Serbia, Slovakia, Slovenia, Tunisia, United Kingdom (WPC 2023).

Reported localities in Hungary: Budapest: Gellért Hill; Pécs (Tömösváry 1882a). Vádé; Visz (Daday 1889b).

New data: nil.

Habitat preference: unknown.

Remarks: Tömösváry (1882a) recorded this species from Budapest, Pécs and Mehádia, but the latter locality is now located in Romania. Unfortunately, many of the specimens listed by Tömösváry (1882a) have been lost (Novák & Dányi 2018), and I could not check the identifications of the Hungarian specimens. However, I had the opportunity to check the specimens from Mehádia, and these proved to be representatives of the genus Ephippiochthonius . As specimens of C. orthodactylus have not been recorded since from the country, the occurrence of this species in Hungary is doubtful.