NICROPHORINAE Kirby, 1837

Species of this subfamily are very distinctive and a familiarity with the British species will serve to place all the members with confidence. The genus Nicrophorus contains about seventy species with a worldwide distribution but the most diverse regions are the Palaearctic and Oriental. They are among the largest and most conspicuous of the staphylinoid beetles. 12-30mm. Head relatively large with prominent eyes and characteristic antennae (see above). Frontoclypeal suture obvious as a transverse impression between the anterior margins of the eyes. Pronotum almost quadrate and usually deeply impressed behind the anterior and posterior margins. Variously pubescent or glabrous. Elytra truncate and often, or usually, with transverse red fascia which generally extend to the epipleurae. Usually almost entirely glabrous and with several longitudinal ridges but without striae. Three or four heavily sclerotized abdominal segments are visible beyond the elytral apex. In most species the male protarsomeres are dilated. The larvae are broadly campodeiform; the integument is pale and lightly sclerotized, except for the head and the legs, and the underside is white or creamy white. There is only a single, unpigmented, ocellus on each side of the head. The abdominal tergites are transverse, each with four small spines, and the anal lobes lack teeth.

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Nicrophorus species are unusual among beetles as they display biparental care of the larvae. They feed and breed on carrion and some species will breed communally on carrion too large to bury. Most species breed at small carcases of rodents and birds. Usually being attracted by the smell, a carcass will attract many individuals and the beetles will fight; males with males and females likewise, for the right to bury and breed on the food source. If a single male arrives at carrion it will wait for a partner to arrive; they attract females by releasing a pheromone from the tip of the abdomen. Females can bury a carcass and raise larvae alone from sperm stored from previous matings. The pair digs a depression beneath the carcass by pushing soil forward with their heads, if the soil is too hard they will move the carcass a short distance to more suitable substrate. Before burying the carcass they remove the fur or feathers and smear it with bactericide and fungicide to slow the decay and make it less attractive to other beetles and flies etc. Before burial the carcass is rolled into a ball. The removed fur etc. is used to line and reinforce the burial chamber, and the complete process of burial may take eight hours. Eggs are laid in the soil and the newly hatched larvae move onto the carcass. Adults feed on the carrion and regurgitate liquid food in response to begging behaviour from the larvae, this is thought to speed larval development and also to help preserve the food. If there are too many larvae the adults will selectively cull them at an early age. Adults protect and provision the larvae throughout their lives, eliminating competition from dipteral larvae etc. Full grown larvae move into the soil to pupate. Adults are most active at night and will sometimes come to light; they occur regularly at m.v. traps used to survey moths. They are often observed to be carrying phoretic mites, in some cases being covered in them, and this is a mutualistic relationship; arriving at a carcass the young mites leave the beetle and start feeding on fly eggs and small larvae thus helping to eliminate competition for the food. Development, depending to some extent on the food source, is usually rapid; eggs hatch within 12-48 hours of being laid, larvae take a week or two to develop and the pupal stage takes 6-8 days to complete. For the purpose of recording these beetles they are readily attracted to carrion traps and may be found in decaying fungi, both terrestrial and arboreal, and sometimes in decaying vegetation and even dung.