Members of the subtribe Philonthina can be recognized among the Staphylininae by the following combination of characters: elytra not overlapping, without plates anterior to the prosternum, neck present and impunctate (Fig. 2.2.2), antennae closer to the nearest eye than to each other (Fig. 2.2.3), punctures of pronotum either not arranged in dorsal rows or these rows consisting of at least 4 punctures (Fig. 2.2.6), and without empodial setae between the tarsal claws (Fig. 2.2.8).

Philonthina is a widespread and diverse subtribe of Staphylininae in North America that was revised by Smetana (1995), Frank (1975) and Frank (1981) and contains many abundant species that are associated with human activity. One large species, Philonthus politus (L.), is often found in compost, around livestock, and on carrion (Fig. 10.4.1). Philonthus caeruleipennis Mannerheim is a common species found in rotting organic (especially fungi) matter in or near forests; this one (Fig. 10.4.2) was found in a compost heap in a wooded backyard. Bisnius blandus (Gravenhorst), a forest specialist, occurs mainly in rotting fungi but also at carrion (Fig. 10.4.3). These and many other Philonthina can be captured in abundance using pitfall or pan traps baited with dung, mushrooms, or carrion. Some species are associated with older trees: adults and larvae of Hesperus apicialis (Say) can be collected from debris in old tree holes and stumps (Fig. 10.4.4), and Laetulonthus laetulus (Say) is attracted to large, freshly killed trees where it hunts invertebrates attracted to sap (Fig. 10.4.5). The majority of Philonthina species in ECAS inhabit moist debris near or at the edge of lakes, ponds, rivers, and streams. Sifting this debris often yields many Erichsonius Fauvel species, the largest in ECAS being E. rosellus Frank (Fig. 10.4.6). The biology, identification and distribution of ECAS Philonthina will be reviewed in a future publication.