Referred to in older literature as Hylophilidae or Xylophilidae, with 3 British species formerly included in the genus Aderus although variously assigned to Hylophilus or Xylophilus.

Euglenes oculatus (Pk.) is associated with decaying hollow Oaks but has also been reared from other deciduous trees. A very local insect of open ancient woodland throughout southern England. Adults may be found on Sambucus (Elder) blossom.
Vanomus brevicornis (Perris) is a late summer species. Larvae develop in decaying Oak, Beech and Elm but also recorded from Pine. A rare and very local English species.
Aderus populneus (Creutzer) is probably more widespread than the literature would suggest.

Adults of this family may be found by beating the foliage of host trees during warm weather, extracting wood debris samples from within hollow trees especially the red wood mould often found in this situation, on blossom and at MV. They fly by night and during the day, in our experience when the temperature is high, and have been recorded from a straw pile and among frass under bark.

Small insects that superficially resemble some Anobiidae but distinguished by Heteromeran tarsi, 5-5-4, which may appear 4-4-4 due to the weakly lobed 3rd pro and meso tarsal segments which conceal the small 4th segment (pseudotetramerous). Basal segments of meso and metatarsi long. Tibial spurs very small. Claws simple, not split.
1.5-2mm. Entirely reddish or brown or with head or head and thorax darker. Finely punctate and with short recumbent pubescence throughout. Antennae long or very long, filiform or slightly serrate, with obvious pubescence. Last segment of maxillary palpi dilated, widely triangular. Eyes large, excised to accommodate antennal insertions, with large facets. Head contracted immediately behind eyes (cf. Anthricidae). Thorax not bordered, narrowed anteriorly and much narrower than elytra at shoulders. Abdomen with 5 visible segments, 1 and 2 connate.

A.populneus (Creutzer) has antennal segments 2 and 3 small, strongly rounded and distinctly shorter than 4.
Euglenes and Vanonus have the third segment as long as the fourth. E.oculatus (Pk.) Head and thorax black, elytra light brown and parallel sided in basal half, gently widened apically. Antenna filiform with all segments elongate in male, 9 and 10 quadrate in female.
V.brevicornis (Perris) is entirely light brown or with head darker, elytra evenly rounded and broadest behind middle. Antennal segments 9 and 10 distinctly transverse forming a gradual club.

The keys in Joy and Buck will separate the British species. Euglenes pygmaeus (DG.), the species given in Buck's work should be oculatus (Pk.), Pygmaeus is not now considered a British species (Allen,AA. 1969 Ent.Mon.Mag. 105, 163-164)