A large family, with 103 British members.  Generally small to medium (1-11mm) elongate-oval beetles often associated with fungi and decaying organic matter.  There are two subfamilies in Britain, containing approximately equal numbers of species.

Largely associated with fungi, Cryptophaginae are nevertheless found in a wide range of habitats.  Cryptophagus micaceus Rey and several Antherophagus spp. are associated with the nests of tree-dwelling Hymenoptera and bumblebees respectively; other species can be found in rotting bracket fungi, beneath loose bark or in compost heaps.  Several members of genus Cryptophagus are synanthropic and found in stored products.

Ootypus globosus (Waltl) is found mainly in the dung of large herbivores, but most of the rest of the Atomariinae can be found in damp areas with decaying vegetation, particularly marshy areas.  Hypocoprinus latridioides Motschulsky is another dung specialist, but has not been found in Britain since the early 20th century.