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American Midland Naturalist Monograph No. 3 



apical portion of the basistyle. An articulated claw (Ds-C) is usually present 

 at or near its apex. The shape of the dististyle, its vestiture, its place of origin 

 from the apical portion of the basistyle, and the place of origin and type of 

 claw are important characters. In Anopheles the dististyle is long, curved, and 

 slender. In most Aedes it is slightly broader medially, somewhat pilose. In 

 Psorophora great modification of the dististyle occurs. This is exhibited by the 

 medially swollen type found in P. ferox, and P. confinnis (Figs. 73, 80), the 

 truncate type of P. varipes with its claw subapical (Fig. 78), and the greatly 

 modified type of P. howardii with its tremendously developed, lateral, hatchet- 

 shaped lobe (Fig. 69). 



Fig. 14. Diagram of Male Terminalia of Anopheles. An-L, anal lobe; Bs, basi- 

 style; Cl-DL, dorsal lobe of claspette; Cl-VL, ventral lobe of claspette; Ds, dis- 

 tistyle; Ds-C, claw of dististyle; I-S, internal spine; iX-S, ninth sternite; IX-T, ninth 

 tergite; Ph. phallosome; Ph-L, leaflets of phallosome; P-S, parabasal spines. 



Claspette (Cl). — The connecting membranous projections between the 

 bases of the basistyles, the interbasal folds (Ib-F), may bear a pair of struc- 

 tures known as the claspettes. Their position is ventrad of the phallosome and 

 in some Aedes can be seen projecting dorso-ventrally in a lateral view. Anoph- 

 eles has the claspettes present as a pair of fleshy, spined, bilobed structures, 

 each being incompletely divided into an outer or dorsal lobe (Cl-DL) and an 

 inner or ventral lobe (Cl-VL). In Aedes there is but one lobe, presumably 

 corresponding to the ventral one of Anopheles, developed into a well-defined 



