]^0. 64] DIPTERA OF CONNECTICUT : TAXONOMY 



179 



40 Head extremely large, hemispherical, the front and face very narrow; 



arista dorsal PIPUNCUUDAE 



Head not unusually large; face or front usually wide 41 



41. Frontal lunule entirely absent, the parafacials not differentiated by a ^ 



suture ■ , : ■ ■ 



Frontal lunule present; parafacials differentiated by a suture which 

 extends above the antennae and is indistinct only in some Conopidae. .44 



42. Anterior crossvein situated at or before the basal fourth of tbe wing- 



second basal and discal cells always united DOLICHOPIDAE 



Anterior crossvein situated far beyond the basal fourth of the wing or 

 the second basal cell complete • ■ ■^■> 



43. Anal cell pointed posteriorly; proboscis never rigid ^"^^^^^^p^^^lDAE 



piercing • • ■ . .^ 



Anal cell not pointed posteriorly; proboscis usually rigid; "^^er a 

 single row of acrostical hairs EMPIDAt 



44 Coxae close together at the base, the legs attached ventrally ..45 



Coxae widely separated at the base, the legs attached toward the 



sides of the thorax; usually leathery or coriaceous flies; ectoparasites ^^ 

 (Pupipara) 



45 Second antennal segment with a longitudinal seam along tbe upper 

 ' outer edge extending almost the whole length; posterior calli defi^ 



nitely formed by a depression extending from behind the base of the 

 wings to above the base of the scutellura (Calypteratae; Muscoidea) . .86 

 Second antennal segment rarely with a well developed dorsal seam, 

 the posterior calli not differentiated (except m Gasterophilus) , 



squamae small ( Acalypteratae) ^^ 



46. Mouth parts vestigial, sunken in a very small ^^^^^g^^^popHiLiDAE 



47 



Mouth parts well developed, the oral opening large 



47 Posterior spiracle with a long hair or bristle on the border in addition 



to the pubescence, (visible only with liigh magnification) o^ 



Posterior spiracle with pubescence only • 



Arista entirely absent; subcostal vein complete ^^"p^^^^^^c'hAeTIDAE 



48. 



flies 



49 



Arista present ,'t' ' ' i i 



49. First ami second veins ending very close together before thP_ basal 



third of the wing; anal cell absent or incomplete AbTtiiuAt 



Second vein always elongate and ending far beyond the first ..oi) 



50. Subcosta complete, free from the first vein and ending m the costa^^ 



(cf. Trupaneidae) ' ' ' 



Subcosta incomplete, or not ending in the costa or the apex cuived^^ 

 forward beyond the bend _ 



51. Subcosta curved forward at nearly a right angle and weakened beyond. 



the bend, the costa fractured at the apex of the ^^'!i'l°f,^^XNEmAE 



almost always pictured trupa 



Subcosta not angularly curved and weakened „■■■'■ ^ 



52. Head broad, fiattened above; scutellum and thorax A^tte^^^^J^L^^^^^^^^'l^AE 



elongate; large files -^ ^„^..u 



Head rather spherical; scutellum usually convex, not ^^^"-^^I'^^'^YdAE 

 cylindrical flies 



53. First segment of the posterior tarsi shortened and ^"^^^g'^^f^BORiDAE 



First segment of the posterior tarsi normal, usually ^«''°^'" ^^'^" *^54 

 second - gg 



54. Anal cell absent 57 



Anal cell present EPHYDRIDAE 



55. Postocellar bristles divergent gg 



Postocellars convergent or absent 



