Burying beetle

 ( Silphidae ) 

Burying beetles or sexton beetles, genus Nicrophorus, are the best-known members of the family Silphidae (). Most of these are black with red markings on the Elytron (forewings). Burying beetles are true to their name—they bury the carcasses of small vertebrates such as and as a Necrophagy for their larvae; this makes them carnivorous. They are unusual among insects in that both the male and female parents take Bi-parental care.

The genus name is sometimes spelled Necrophorus in older texts: this was an unjustified emendation by Carl Peter Thunberg (1789) of Fabricius's original name, and is not valid under the ICZN.

The American burying beetle ( Nicrophorus americanus) has been on the U.S. endangered species list since 1989. This species was native to 35 U.S. states but now is only known to exist in 9.

An example of a species of Nicrophorus that displays this form of bi-parental care and burying activity is Nicrophorus nepalensis. Pairs of Nicrophorus nepalensis prepare carcasses and care for the developing larvae in a joint fashion. After burying a carcass, the beetles mate and lay eggs near/on the carcass. When the eggs hatch into larvae they begin feeding on the flesh of the carcass. The adults remain until the larvae begin to pupate.

Burying beetle life cycle

The prospective parents begin to dig a hole below the carcass. While doing so, and after removing all hair from the carcass, the beetles cover the animal with antibacterial and antifungal oral and anal secretions, slowing the decay of the carcass and preventing the smell of rotting flesh from attracting competition. The carcass is formed into a ball and the fur or feathers stripped away and used to line and reinforce the crypt, also known as a nursery, where the carcass will remain until the flesh has been completely consumed. The burial process can take around 8 hours. Several pairs of beetles may cooperate to bury large carcasses and then raise their broods communally.

The female burying beetle lays eggs in the soil around the crypt. The larvae hatch after a few days and move into a pit in the carcass which the parents have created. Although the larvae are able to feed themselves, both parents also feed the larvae in response to begging: they digest the flesh and regurgitate liquid food for the larvae to feed on, a form of progressive provisioning. This probably speeds up larval development. It is also thought the parent beetles can produce secretions from head glands that have anti-microbial activity, inhibiting the growth of bacteria and fungi on the vertebrate corpse.

The adult beetles continue to protect the larvae, which take several days to mature. Many competitors make this task difficult, e.g. Calliphoridae and or burying beetles of either another or the same species. Throughout the entirety of the larva's development, the parents fight off these competitors all the while maintaining an ideal nursery inside the carcass for their offspring. The final-stage larvae migrate into the soil and pupate, transforming from larvae to fully formed adult beetles.

Parental care (and particularly biparental care) is quite rare among that are not eusocial (e.g. and ). Burying beetles are exceptional in exhibiting this trait, and thus fall under the category of subsocial insects.Trumbo, S.T. 1994. Interspecific competition, brood parasitism, and the evolution of biparental cooperation in burying beetles. Oikos. 69:241–249.

there are over 60 valid, extant species in the genus ''Nicrophorus'' although a few undescribed species and synonyms remain to be worked up.