Histeridae is a family of beetles commonly known as clown beetles or hister beetles. There are more than 410 genera and 4,800 described species in Histeridae worldwide, with more than 500 species in North America. They can be identified by their shortened elytra, which leave two tergites exposed, and also by their elbowed antennae with clubbed ends. These predatory feeders are most active at night and will fake death if threatened. Hister beetles occupy almost any kind of niche throughout the world. They have also been useful for estimation of time of death during forensic investigations. Also, certain species are used for controlling houseflies and livestock pests that infest dung.

Histeridae was first named by Leonard Gyllenhaal. Histeridae has two common names, the clown beetle and the hister beetle. There have been several theories which explain the origin of these names. One theory for "hister" comes from the work of Juvenal, a Roman poet. Juvenal used the word "hister" to mean a dirty, lowly being. Another theory for the origin of this beetle's name stems from the fact that in Latin, "hister" means actor, and these beetles play dead when disturbed.

Hister beetles can be identified by their elytra, which are shorter than the abdomen and typically leave two of the seven tergites exposed. Their elytra are typically glabrous and black or metallic green, and their protibiae are flattened and toothed. Hister beetles have specialized heads that can retract into their prothorax and two lamellate antennae with clubbed ends. Most beetles in this family are flattened and oval in shape.

Hister beetles can be found throughout the world in various habitats. The majority of Histeridae species prefer dried or decaying habitats. They can be found dung or carrion, dead vegetation, tree bark, burrows, and ant or termite colonies. Histeridae live in widespread habitats because they feed on other arthropods and live in areas where their prey is found, such as carrion and dung, where maggots can be found.

The oldest record of the family is Antigracilus from the Aptian age of the Cretaceous period, in the Yixian Formation of China. Antigracilus is the sister species to all living members of the family. The oldest crown group representatives are known from Burmese amber around 99 million years old. This includes beetles belonging to the extant subfamily Haeteriinae, and the extant genus Onthophilus.

The larval and adult forms of Histeridae feed on dung, carrion, decomposing vegetation, and other insects,. Hister beetles are able to locate both dung and carrion with their sense of smell. When found on dung, carrion and vegetation, hister beetles typically feed on the fly larvae found there. The hister beetle will feed on soft-bodied insect eggs and larvae, particularly on flies. Some species of Histeridae will even feed on other Histeridae.

Some Histeridae species live in a nest with ants and termites. Some of these beetles are fed by the ants, while others simply feed on leftover insect larvae that the ants do not want.However, in their adult stage, some Psiloscelis will actually feed on adult ants.

Because Histeridae are predaceous, they can be utilized to control pests, but must be stored in isolation, as they can be cannibalistic. The hister beetles have been useful in the control of pest flies in poultry houses and pastures, and also against pest beetles of stored food products.