Chironomus utahensis Malloch and Chironomus harpi new species and their karyosystematic relationships to other species in the decorus -group of Chironomus (Chironomidae: Diptera)

Adult, pupal and larval morphology and karyotypes of Chironomus utahensis Malloch and Chironomus harpi , spec. nov. are described. Adults of C. utahensis resemble Chironomus atrella (Townes) and C. anthracinus Zetterstedt; however, the resemblance is apparently from convergence. The dark coloration, clypeus narrower than the antennal pedicel, long foretarsal beard, short, rather broad, pale anal point and the almost straight superior volsella will differentiate it from other members of the genus. Adults of C. harpi most closely resembly C. decorus Johannsen and C. maturus Johannsen but the male genitalia are distinctive in having an almost straight superior volsella which is blunt tipped and a narrower anal point with a weakly delimited tongue-like apical lobe.