34 



American Midland Naturalist Monograph No. 3 



Aedes, Psorophora, and Culiseta. It is vestigial or absent, however, in Anopheles 

 and Uranotaenia, which have the anal lobe (An-L) or membrane unsupported. 

 Although the tenth sternite may be characteristically knobbed or toothed api- 

 cally in many species of several genera, the terminal armature has been found 

 most valuable taxonomically in the genus Culex. This armature consists of a 

 crown of spines in the subgenus Culex and a comb-like row of teeth in the 

 subgenera Neoculex and Melanoconion. 



Phallosome (Ph). — The phallosome (mesosome) is a chitinous, tube-1'ke 

 structure surrounding the penis. It is situated just ventrad of the proctiger and 

 is held in position by supporting structures, the basal plates (B-P) and para- 

 meres (Pm), which articulate with the basal processes of the tenth sternite, 

 the phallosome, and with each other. The phallosome furnishes some of the 

 most reliable generic and subgeneric characters; its variations range from a 

 long, slender tube with apical leaflets in Anopheles to complex toothed plates 

 in Culex, Uranotaenia and Deinocerites. 



XS-DA 

 Pm 



Fig. 12. Diagram of male terminalia of Aedes. A-L, apical lobe; A-M, anal 

 membrane; B-L, basal lobe; B-P, basal plate; Bs, basistyle ; Cl-F, filament of clasp- 

 ette; Cl-S, stem of claspetfe; Ds, disfistyle ; Ds-C, claw of dististyle; Ib-F, interbasal 

 fold; IX-T, ninth tergite; IXT-L, lobe of ninth tergite; Ph. phallosome; Pm, para- 

 mere; X-S, tenth sternite; XS-DA, dorsal arm of tenth sternite. 



