Circocerus Motschulsky, 1855

Chandler, Donald S., 2013, Further Notes on the New World Pselaphinae (Coleoptera: Staphylinidae) Described by Victor Motschulsky, The Coleopterists Bulletin 67 (3), pp. 321-327 : 324

Circocerus Motschulsky, 1855 and Apharus Reitter, 1882

Motschulsky (1855) described the new genus and species Circocerus perplexus from Obispo, and he described Circocerus batrisioides the following year (1856) from New Orleans, Louisiana. The types of C. perplexus were examined in 2005, and this species was found to be congeneric with members of Apharus , whose type species is Apharus muelleri Reitter from Brazil. Before synonymizing the two genera, a loan of A. muelleri was pursued. Reitter had listed the specimen as being in the collection of Hans Simon of Stuttgart, and the major collections of Europe with extensive Pselaphinae holdings were contacted about this type without success. A pertinent suggestion was that Dr. Wolfgang Schawaller at the Staatliches Museum für Naturkunde, Stuttgart, should be contacted on this matter. Dr. Schawaller (2007, personal communication) indicated that Hans Simon lived and died in Stuttgart, and presented about 25,000 beetles to the Stuttgart Museum around 1875–1879. Very few of these specimens, all from the Stuttgart area, are present in the collection today, with the rest being possibly destroyed during the two wars. This type is here regarded as lost, probably destroyed.

However, Reitter (1882: 130) provides a thorough description and a habitus illustration of A. muelleri , such that synonymy of Circocerus and the more junior Apharus can be confidently proposed. A complication is that the other species in this genus, C. batrisioides from North America, is the only well-known species, but it is not congeneric. A generic junior synonym, Upoluna Schaufuss, 1886 , is available for placement of this species. Both genera are redescribed below, and problems in separating Upoluna from the nominate subgenus of Hamotus Aubé are discussed.