470 

 48. Chironomus festivus Say 



Chironomus festivus Say, Jour. Acad. Nat. Sci. Phil., Vol. 3, p. 13, sp. 2. 1823. 

 Chironomus lineaUis Say, ibid., p. 14, sp. 5. 



Chirononms lineola Wiedemann, Ausserenrop. Z'SNeifl. Ins., Vol. 1, 1828, p. 17, 

 sp. 6. 



Male. — Bright green, shining. Antennae and their plumes yellow, 

 flagellum except the base fuscous ; palpi and face yellow. Mesonotum 

 with three reddish vittae ; sternopleura and postnotum reddish. Abdo- 

 men bright green, the apices of segments 2-6 narrowly blackened on 

 center. Legs reddish yellow. Wings clear, cross vein not infuscated 

 or very slightly so. Body hairs yellow. 



Antenna about one and a half times as long as head and thorax to- 

 gether, antepenultimate joint of palpi as long as the next two joints 

 together, ultimate joint slightly shorter than penultimate. Pronotum 

 continuous to upper level of mesonotum, linear on upper half. 

 Thoracic hairs normal. Second segment of abdomen with a slight 

 ridgelike apex ; segments 3-5 almost invariably with two small wartlike 

 protuberances in the black portion close to apical margin, one on each 

 side of the median line, and slightly cephalad of these, and much 

 closer together, two small smooth areas which may be sensory organs 

 but have the appearance of hair sockets; sixth segment with a slight 

 central apical callosity; hypopygium (PI. XXXIII, Fig. 14) with the 

 dorsal process black, glossy, the apical portion of the lateral arm dis- 

 tinctly longer than the basal. Legs rather stout, basal joint of fore 

 tarsi two thirds longer than tibia ( 105 : 65), outer surface of fore tarsi 

 from middle of basal joint to middle of fourth with very long hairs; 

 mid and hind legs with long surface hairs ; apices of mid and hind 

 femora with a brown flattened scalelike process on the anterior surface 

 which projects slightly beyond apex. Wings narrow ; cross vein be- 

 yond middle of wing ; cubitus forking very slightly beyond cross vein. 



Female. — Similar to the male in col@r except that only the apex of 

 the flagellum is fuscous, that there is a blackish brown median line on 

 central portion of the mesonotum in addition to the reddish vittae, and 

 that the fore tibiae, fore tarsi from middle of basal joint, and the apices 

 of the other tarsi are brown. The fore tarsi have no long hairs, the 

 apical process on mid and hind femora is rather stouter than in the 

 male, and the abdomen has not wartlike processes at apices of seg- 

 ments. 



Length, 8-9 mm. 



Illinois localities : St. Joseph, Monticello, Lilly, Kampsville, and 

 Havana, dates ranging from June 2 to August 21. 



