Status of Eustilicus Sharp, Trochoderus Sharp, Deroderus Sharp, and Stilocharis Sharp (Coleoptera: Staphylinidae: Paederinae: Paederini) with implications for classification of the Medonina and Stilicina

Based on a study of adults, Trochoderus Sharp and Stilicolina Casey are placed as subjective synonyms of Eustilicus Sharp, Lypomedon Blackwelder is removed from Stilomedon Sharp and treated as a subjective synonym of Deroderus Sharp, Stilocharis Sharp is removed from Lithocharis Dejean and treated as a distinct genus, and Deroderus difftcilis Sharp is transferred to Rugilus Leach. Diagnoses are provided for Eustilicus, Deroderus, Stilocharis, Rugilus, and Stiliderus Mots. Although Eustilicus, Rugilus, and Stiliderus are typical members of the subtribe Stilicina, and Stilocharis and Deroderus are typical Medonina, adults of Eustilicus, Stilocharis, and Deroderus possess two synapomorphies to the exclusion of all other Paederinae. Evidently Eustilicus is more closely related to Deroderus and Stilocharis than to Rugilus or other genera in the Stilicina. Further studies may show that the Stilicina and Medonina should be combined.