168 American Midland Naturalist Monograph No. 3 



MALE TERMINALIA 



l.Disfistyle furcate near base, inserted well before apex of basistyle 



cinereus Meigen, p. 235 



Dististyle not furcate, inserted at apex of basistyle 2 



2. Claspettes absent; basistyle very short (about V/i times as long as wide) 



aegypli (Linn.), p. 227 



Claspettes present; basistyle elongate (2'/2 to 4 times as long as wide) 3 



3. Claspette stem crowned with a dense tuft of setae, the filament lacking; claw of 



dististyle subapical in position, arising from a small thumb-like projection at 



apical fifth of dististyle vexans (Meigen), p. 231 



Claspette with a distinct filament; claw of dististyle apical in position 4 



4. Claspette filament broadly expanded, contorted, leaf-like, arising from a short 



lateral branch near middle of claspette stem thibaulti D. and K., p. 213 



Claspette filament ligulate to blade-like, arising at apex of claspette stem 5 



5. Apical lobe of basistyle absent; basal lobe without an enlarged spine 6 



Apical lobe of basistyle present; basal lobe either with or without an enlarged 



spine 10 



6. Basistyle with a small dense patch of long hairs arising on inner face at apical 



third; terminal claw about half as long as dististyle triseriatus (Say), p. 225 



Basistyle without a dense patch of long hairs arising on inner face at apical 

 third; terminal claw never more than one-third as long as dististyle 7 



7. Claspette filament sharply pointed, with a prominent sharp retrorse projection 



medially laeniorhvnchus (Wied.), p. 209 



Claspette filament slender, curved, without a retrorse projection - 8 



8. Dististyle of nearly equal width throughout, glabrous except for a few short setae 



near apex; basistyle distinctly conical in shape; lobes of 9th tergite incon- 



spicous, without spines or setae atropalpus (Coq.), p. 221 



Dististyle distinctly broadened before middle, pilose; basistyle cylindrical in 

 shape; lobes of 9th tergite small but distinct, armed with short spine-like setae 

 9 



9. Basal lobe of basistyle conical, rounded at apex, prominent 



mitchellae (Dyar), p. 197 



Basal Jobe of basistyle only slightly rounded, not prominent .^ 



sollicitaus (Walker), p. 200 



nigromaculis (Ludlow), p. 199 



10. Basal lobe of basistyle without an enlarged spine; apical lobe clothed with 



numerous short flattened setae canadensis (Theob.), p. 174 



maihesoni Middk., p. 194 

 Basal lobe of basistyle with an enlarged spine; apical lobe clothed with short 

 slender setae 1 I 



1 1. Basal lobe of basistyle with a short stout spine, in addition to a long stout spine 



and numerous setae dorsalis (Meigen), p. 180 



Basal lobe without a short stout spine, bearing only a single long stout spine and 

 numerous setae 12 



12. Claspette filament with a median retrorse pointed projection 



infirmakis D. and K., p. 191 



(rivittalus (Coq.), p. 218 

 Claspette filament without a median retrorse pointed projection 13 



13. Claspette stem stout and sinuous, broad medially, constricted basally and api- 



cally, the median portion much broader than the claspette filament 



allanllcus D. and K.. p. 171 



Claspette stem slender, never more than slightly broader than the claspette fila- 

 ment 14 



14. Claspette stem sinuous; enlarged spine of basal lobe arising from a stout elon- 



gated tubercle near base lormentor D. and K., p. 214 



Claspette stem straight or curved, not sinuous; enlarged spine of basal lobe aris- 

 ing from a short tubercle 15 



15. Filament of claspette ligulate, curved, not expanded blade-like on convex side 



