A small family, Botheridae has just five British representatives, all small (1-3mm), dark, elongate often-shining species.  Four of these (Anommatus diecki Ritter, A. duodecimstriatus (Müller), Oxylaemus cylindricus (Panzer) and O. variolosus (Dufour)) are subterranean while the fifth, Teredus cylindricus (Olivier) is a predatory species found in hollow oaks in association with Anobiidae or Lassius brunneus ants.  Both Oxylaemus species are specialists of ancient forest: indeed, O. cylindricus has not been found in Britain since the 19th century and may well be extinct here.