64 



MISC. PUBLICATION 336, U. S. DEPT. OF AGRICULTURE 



Outstanding scales of wing, at least on branches of vein 2, slightly or 

 distinctly broadened (fig. 19, B) ; occiput with some broad, flat scales 



(except in Theobaldia melanura) 23 



22. Abdomen usually with a few yellowish or dingy white scales at base 

 of some segments, or with narrow transverse bands ; tips of segments 

 sometimes slightly pale-scaled and seventh segment frequently en- 

 tirely pale-scaled; three or four groups of white scales on side of 

 thorax. Abundant in some sections of South and East 



Culex salinarius 



Abdomen dark-scaled above except for lateral white spots on some 

 segments; scaling on pleurae somewhat variable but frequently 

 entirely lacking or, if present, limited as a rule to less than a half 

 dozen scales in any of the groups. Abundant in Florida, rare else- 

 where Culex nigripalpus 



Figuee 19. — Representative shapes of the outstanding wing scales on the central 

 portion of the forks of vein 2: A, Culex {Culex) ; B, Culex (Melanoconion) . 



23. Occiput with broad dusky or pale appressed scales in front, sometimes 



limited to a narrow border along the eyes, but extending to or nearly 

 to vertex ; abdominal segments with or without narrow white bands. 



Small Culex, subgenus Melanoconion 24 



Occiput without flat scales. [Proboscis unusually long (longer than 

 abdomen) ; wing scales dense and distinctly broadened; spiracular 

 bristles and ventral setae at base of subcosta present as in Theobaldia 

 inomata (lacking in all Culex).'] A comparatively rare species, 

 greatly resembling typical Culex Theobaldia melanura 



24. Occiput mostly covered with broad appressed scales, the narrow scales 



limited to a median line or a small triangular patch. [Tip of male 



abdomen much enlarged in Culex peccator.] Culex pilosus 



Culex peccator 



Occiput with a large median triangular area of narrow scales extending 



nearly to the vertex, the broad appressed scales often reduced to a 



narrow line bordering the eyes. [Mesonotal scaling often bronzy or 



golden. ] Culex erraticus 



(Adults of the Melanoconion species cannot be identified with certainty 

 except by characters of the male terminalia, which are shown in a 

 separate table.) 



