22 Bulletin of Zoological Nomenclature 49( 1 ) March 1 992 Case 2764 Acrolocha Thomson, 1858 (Insecta, Coleoptera): proposed conservation, and Coprophilus Latreille, 1829: proposed designation of Staphylinus striatulus Fabricius, 1792 as the type species Margaret K. Thayer Field Museum of Natural History, Roosevelt Road at Lake Shore Drive, Chicago, Illinois 60605, U.S.A. Abstract. The purpose of this appHcation is to conserve the usage of the names Acrolocha Thomson, 1858 and Coprophilus Latreille, 1829 for genera of rove beetles (staphylinidae). Acrolocha is threatened by the senior objective synonym Elonium Leach in Samouelle, 1819, a name that has caused confusion because it has been used for two completely different taxa, Acrolocha and Coprophilus in the omaliinae and OXYTELINAE respectively. The usage of Coprophilus is maintained by the proposed designation of Staphylinus striatulus Fabricius, 1 792 as the type species. 1. Leach in Samouelle (1819, p. 175) erected the new genus Elonium, giving Omalium striatum as its type and only included species; he did not cite an author's name with the species. The name Elonium has been credited to Samouelle by some subsequent authors. 2. Stephens (1829a, p. 25) and Curtis (1829, col. 29) both placed Omalium striatum Gravenhorst, 1802 (p. 119) in Omalium Gravenhorst, 1802 (p. Ill) and Staphylinus striatulus Fabricius, 1792 (p. 525) in Elonium, apparently regarding Leach's citation of the former species as an error for the latter. Stephens (1833, col. 108; 1834, p. 349) continued to place O. striatum Gravenhorst in Omalium and (1833, col. 107) S. striatulus Fabricius in Elonium (although he treated Elonium as a synonym of Coprophilus Latreille, 1829; see para. 3). 3. Latreille (1829, p. 439) erected the new genus Coprophilus, with "Omalium rugosum Gravenhorst' as the only species named. Gravenhorst ( 1 802, p. 1 1 5) attributed Staphylinus rugosus (placed in Omalium) to Olivier (1795; genus no. 42, p. 30), who in turn referred it to S. rugosus Fabricius, 1775 (p. 267). Olivier repeated Fabricius's description and mentioned two more Fabrician references, as well as providing illus-trations (pi. 5, fig. 43). It follows from this that the nominal species Staphylinus rugosus Fabricius, 1775 is the type of Coprophilus by monotypy. However, at least since 1829 (Curtis, cols. 29, 30; Stephens, 1829a, p. 24; 1829b, pp. 293, 297), rugosus Fabricius has been consistently placed in Oxytelus Gravenhorst, 1802. The name rugosum 'Ol.' or 'Grav.' has been treated as a synonym of Staphylinus striatulus Fabricius, 1792 and placed in Elonium or Coprophilus (see para. 2). Like Stephens (1833), Erichson (1839, p. 609) and Lacordaire (1854, p. 120) listed Elonium as a synonym of the younger name Coprophilus without comment. These authors and also Kraatz (1857, p. 1000) kept striatum Gravenhorst in Omalium.