Cercyon melanocephalus (Linnaeus, 1758)

Widely distributed and generally common throughout the British Isles including Scilly, the Western Scottish Isles, Orkney and Shetland (NBN). Very common and usually abundant throughout the Watford area from early spring through to October or November depending on season. Adults may be netted in flight from many reasonably open habitats but especially from dung pasture, and samples of dung will almost always contain them, usually in good numbers. The first specimens appear during warm days towards the end of March and by late April they are common everywhere. They occasionally occur in decaying vegetable matter of all kinds, often in the company of other Cercyon species: we have extracted them from compost during May and June in town centre gardens, and from heaps of decaying pond clearance from Cassiobury park during May. Through September 2006 they were abundant in large terrestrial bracket fungi under Fagus on the margins of Whippendell wood. They may be attracted to light in many situations

Although tiny this species can usually be recognised in the field with a X10 lens: the elytral colour and pattern are distinctive but specimens of C.haemorrhoidalis (Fab.) are often closely similar.

2.2-3mm. Head shiny black, punctate and without microsculpture. Clypeal margin gently sinuate in front. Palps black or very dark, as long as antennae. Antennae 9 segmented with 3 segmented club, brown or piceous, club black. Pronotum entirely black, puncturation a little finer than on head, finely bordered laterally. Hind angles obtuse, sides evenly rounded when viewed from above. Sometimes with a small, well defined longitudinal impression in front of scutellum. Elytra with ten well impressed and punctate striae: 7-9 evanescent towards base, 10 sometimes (often) present only in basal half. Entirely punctate although this becomes weaker towards apex, shining between punctures, without microsculpture. Ground colour varies from yellow to dark reddish brown, the basal triangular dark marks around scutellum and beneath humeral prominence are constant (Hansen). Epipleurs black to dark brown (cf. C.haemorrhoidalis). Scutellum longer than width at base, puncturation finer than that on surrounding elytra. Pronotum and elytra form a single curve when viewed from the side. Legs yellowish brown to dark reddish brown, tarsi lighter. Tibiae with strong spines on outer side, protibiae rounded at apex (cf. C.littoralis), meso and meta-tibiae with two long and unequal terminal spurs on inside. All tarsi 5 segmented, basal segment longer than second. Claws smooth and curved.

Description from 10 Watford specimens at X40