PROC. ENTOMOL. SOC. WASH. 102(4), 2000, pp. 991-1002 A NEW SPECIES OF THE SUBGENUS SABETHOIDES OF SABETHES (DIPTERA: CULICIDAE) FROM VENEZUELA AND BRAZIL Dusty A. Moses, Theresa M. Howard, and Ralph E. Harbach (DAM) Department of Biology, Cumberland College, 7000 College Station Drive, Wil- liamsburg, KY 40769, U.S.A.; (TMH, REH) Department of Entomology, The Natural History Museum, Cromwell Road, London SW7 5BD, U.K. (e-mail: t.howard@nhm.ac. uk; r.harbach@nhm.ac.uk) Abstract. —The adult male, pupa and larva of Sabethes (Sabethoides) conditus, n. sp., are described from localities in western Brazil and northern Venezuela. The species is distinguished from Sabethes chloropterus (von Humboldt), which it closely resembles in all life stages. Key Words: Diptera, Culicidae, Sabethes, Sabethoides, new species, mosquito, Brazil, Venezuela Mosquitoes of subgenus Sabethoides Theobald of genus Sabethes Robineau-Des- voidy are some of the more common insects in Neotropical forests, yet they are poorly known and rarely studied. No significant taxonomic research has been done on the subgenus since Lane (1953). This is sur- prising since one of the species, Sa. chlo- ropterus (von Humboldt), has repeatedly been found infected with St. Louis enceph- alitis virus (Galindo et al. 1959) and is known to transmit yellow fever virus to hu- mans (Galindo et al. 1956). In addition to Sa. chloropterus, the subgenus includes 5"^. glaucodaemon (Dyar and Shannon), Sa. tri- dentatus Cerqueira, and at least 2 undescri- bed species. With the addition of the new species described in this paper, Sabethoides now includes 4 formally recognized spe- cies. The new species described here very closely resembles Sa. chloropterus in all life stages, and undoubtedly has been con- fused as this species in the past. For this reason, future study may indicate that it is also a vector of arboviruses. Materials and Methods This study is based on specimens bor- rowed from the National Museum of Nat- ural History, Smithsonian Institution, Washington, DC. Observations of the adults were made under simulated natural light. Larval and pupal chaetotaxy were studied using a combination of bright field and dif- ferential interference contrast microscopy. Measurements and counts were taken from all specimens of the type series where the structures in question were present. Num- bers in parentheses represent modes of the reported ranges unless indicated otherwise. The form of presentation, descriptive ter- minology and abbreviations used in the spe- cies description follow Harbach and Knight (1980, 1982) and recent papers published as part of an ongoing revision of the genus Sabethes (Harbach and Peyton 1991; Har-