There are four morphologically similar species in the Holarctic genus Acartophthalmus Czerny, the only genus confidently placed in the family Acartophthalmidae, with Acartophthalmites only tentatively allied. This small grayish family is often found in association with rotting fungi and carrion in damp woodlands (Chandler 1982, McAlpine 1987, Papp & Ozerov 1998), but adults have also been collected on dung, sap (Greve 1988, Máca & Rohácek 1983) and flowers.

Acartophthalmus bicolor Oldenberg has been observed ovipositing on a dead snake in Russia, and larvae have been reared from decaying meat (Papp & Ozerov 1998). Males have been observed waiting for females on decaying organic matter, protecting patches of territory from other males; resident males met invaders by flapping wings, with the smaller male usually retreating (Papp & Ozerov 1998). The genus was last treated by Nilsson (2009).

The Holarctic Acartophthalmus nigrinus (Zetterdtedt) is by far the most commonly collected species. It can be found in relatively large numbers in some habitats, and appears to be more abundant in the boreal region. The species of this genus can be identified as follows:

1. Frons and antennae dark brown to black. Face usually dark with
centre sometimes distinctly yellow. .................................. 2
-- Anterior part of frons and most of antennae yellow. Face entirely
yellow. ......................................................................... 3
2. Fore coxa paler than side of thorax. Wing often with slight
infuscation along anterior margin. Holarctic, common.
.................................................. A. nigrinus Zetterstedt
-- Fore coxa entirely black. Wing clear. Russian Far East.
........................................................ A. latrinalis Ozerov
3. Bristles along oral margin black, well developed. Fore and mid
legs yellowish. Wings smoke-coloured along anterior margin.
Larger species, body length 2.0-2.2 mm. Holarctic.
....................................................... A. bicolor Oldenberg
-- Bristles along oral margin pale yellow, weakly developed. All
legs dark. Wings clear. Smaller species, body length 1.0-1.5
mm. Europe. ............................................... A. pusio Frey