50 M. W. R. de V. GRAHAM 



8 (7) Surface of antennal scape dull, with granulate sculpture. Head and pronotum 



with irregular, extremely densely distributed punctures which often leave 

 no interspaces, in places the sculpture may be rugose-punctate 



rugulosa Forster (p. 51) 



- Surface of antennal scape, at least on its inner aspect, more or less shiny. 



Punctures of head and pronotum more regular and less crowded, leaving 



at least some narrow smooth interspaces ...... 9 



9 (8) Antennal scape longitudinally striate-reticulate. Pronotal collar with 



circular or subcircular piliferous punctures . . nigra Latreille (p. 51) 



- Antennal scape having its outer aspect finely granulate, its inner aspect nearly 



smooth. Pronotal collar with most of the piliferous punctures irregular in 

 shape [Near East] ...... irregularis Boucek (p. 51) 



10 (7) Piliferous punctures of pronotum and head subcircular and fairly regularly 



distributed, the interspaces smooth and on the average about as wide as the 

 diameter of the punctures, on the head sometimes slightly less wide ; 

 pronotal collar semicircular. Females with head about as high as broad ; 

 distal segments of antennal funicle transverse. Mid and hind tarsi in both 

 sexes black ....... nigripes Curtis (p. 53) 



- Piliferous punctures of pronotum and head more widely-spaced, at least some 



of the interspaces wider than the diameter of the punctures ; the inter- 

 spaces on the pronotum sometimes with traces of alutaceous sculpture, or 

 rugulose. Females with head often higher than broad ; distal segments 

 of funicle sometimes not transverse . . . . . . . n 



1 1 (10) Body, including the head, strongly depressed, flattened, not more than 1 -8 mm. 



in length. Scutellum without a transverse line, or with this indicated only 

 laterally by one or two punctures. Females with head in profile about 

 three times as high as thick ; antennal scape very short ; second segment 

 of funicle much smaller than the third, almost anelliform. Males with 

 flagellum clothed with hairs whose length is about equal to the breadth of 

 the segments that bear them ; first funicular segment about four times as 

 long as the pedicellus. [North and Central America] drosophilae Ashmead 



- Body not remarkably flattened ; length sometimes greater. Scutellum with 



or without a transverse punctate line. The other characters not agreeing 



with the above ........... 12 



12 (11) Pronotal collar more or less rugulose, with at least a transverse band of 



longitudinal rugae near the hind margin, this band indistinct in some small 

 specimens. Transverse punctate line of scutellum complete. Tarsi 

 usually testaceous at least proximally (occasionally wholly black in 

 erythromera). Females with distal segments of antennal funicle transverse 13 



- Pronotal collar without rugae, the interspaces between the scattered punc- 



tures smooth or finely alutaceous. Transverse line of scutellum in smaller 

 specimens interrupted or absent. Tarsi mainly dark. Larger females with 

 the distal segments of the antennal funicle not or hardly transverse . . 14 



13 (12) Myrmecophilous species associated with Lasius fuliginosus. Females with 



legs and antennae unusually thick ; antennal flagellum very compact, 

 third funicular segment about 1-5 times as broad as long ; gaster broad, 

 its tergites smooth ; pronotal collar often with indications of a median 

 longitudinal rugose groove ; only the first segment of the tarsi pale 



crassicomis Boucek (p. 54) 



- Species not myrmecophilous. Legs and antennae not unusually thick or 



compact ; third funicular segment in female relatively less transverse ; 

 gaster less broad, the tergites in most specimens with some delicate 



