Euryptilium Matthews, 1872
POLYPHAGA Emery, 1886
STAPHYLINOIDEA Latreille, 1802
PTILIINAE Erichson, 1845
E. gillmeisteri Flach, 1889
E. saxonicum (Gillmeister, 1845)
Includes two European species, both of which are widespread though very local and rare, and both of which extend into the UK. They are tiny beetles, 0.7-0.9 mm in length, elongate and discontinuous in outline, the body is weakly convex, pale to dark brown or sometimes almost black, finely pubescent and with at least some obvious granular microsculpture, and the appendages are paler brown. The following features will distinguish the genus among our UK fauna. Head smoothly curved from above, smooth and without structure between weakly convex eyes that follow the outline. Antennae inserted laterally in front of the eyes, 11-segmented; two basal segments enlarged, segments 3-8 elongate and narrow, 9-11 elongate and gradually, albeit only slightly, wider. Pronotum transverse, broadest in front of obtuse posterior angles and smoothly narrowed to a rounded apical margin (the anterior angles usually not visible from above), basal margin more-or-less straight and much wider than the apical margin, surface evenly convex, finely granulate and microsculptured, without depressions, lines or fovea. Prosternum without a process, front coxae close together, usually in contact. Middle coxae narrowly separated by a fine mesosternal process. Metasternum with a median furrow and narrowly extended between the hind coxae where it is produced into two tiny teeth, lateral metasternal margins close to the elytral epipleura which are not demarked by a longitudinal keel. Elytra completely covering the abdomen, at most only the tip of the pygidium (which terminates in two very fine teeth) visible, only weakly dilated from the shoulders to separately and rather narrowly-rounded apical margins, surface evenly convex and without structure, humeral angle produced into a small but prominent tooth which is often hidden under the pronotum. The species may be distinguished as follows:
-0.83-0.90 mm. Body usually dark brown, antennae pale brown to yellowish. Granules on the pronotum very fine, weaker than those on the elytra, and usually only visible towards the base. Cellular microsculpture on the pronotum distinct and increasing in size towards the base.
-E. gillmeisteri Flach, 1889
-0.70-0.85 mm. Body usually very dark, almost black, antennae darker brown or yellowish with the basal segments darker. Granules on the pronotum distinct throughout, dense and similar to those on the elytra. Cellular microsculpture on the pronotum very fine, appearing obsolete in places.
-E. saxonicum (Gillmeister, 1845)
Euryptilium gillmeisteri Flach, 1889
E. gillmeisteri is known from scattered records throughout Europe from the northern Mediterranean to southern Norway and Sweden; it is generally very local and rare and seems to be a more southern species. Adults have been recorded in March and from July to November; they are associated with decaying trees in deciduous woodland and may be found among decaying wood, fungi or old nest material. Included in the UK list from several specimens found among leaf litter and bird droppings at the base of a mature Oak in Yorkshire during 1995 (Johnson. 2001).
Euryptilium saxonicum (Gillmeister, 1845)
E. saxonicum is also widespread in Europe, especially in the north where it occurs above the Arctic Circle in Norway and Sweden; it is generally much more frequently recorded than the previous species and seems to have a more northerly distribution. In the UK there are records scattered across Southern and Central England and Wales, and there are a very few from the northern Scottish Highlands. The species is usually associated with open woodland and adults have been found among decaying sporocarps, damp bark and leaf-litter and matted grass near decaying or damaged trees. Adults are present year-round; they are active over a long season from late winter or early spring and they peak in abundance during May and June.