Cerylon histeroides
A very small beetle, 1.8 to 2.3 mm. Adults are dark brown, sometimes dark reddish-brown or even blackish. The pronotum is broadly quadrate and strongly punctured.
It is superficially similar to C. fagi but is generally more slender in appearance and readily distinguished by the form of the antennae; here segments 4-7 are quadrate to slightly elongate, segments 8 and 9 are transverse and widest at, or very close to, the apex, and none are rounded laterally.

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Adults and larvae inhabit a range of both deciduous and coniferous trees, often in woodland habitats, but not exclusively so. They may often be found beneath bark.
Can be found in most months of the year.
It is generally common across England and Wales though less so in the north and very local and sporadic further north.
Fairly frequent in Leicestershire and Rutland.
Leicestershire & Rutland Map
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MAP KEY:
Yellow squares = NBN records (all known data)
Coloured circles = NatureSpot records: 2020+ | 2015-2019 | pre-2015