PTEROMALIDAE OF N.W. EUROPE 157 



8 (7) Smaller species (1 -8 to 2-2 mm.). Antennal scape as long as an eye. Gaster 



with pygostylar bristles subequal in length . . politu (Walker) (p. 162) 



Usually larger (i-8 to 4 mm.) but if less than 2-4 mm., then the antennal scape 

 is distinctly shorter than an eye. Usually one bristle of each pygostyle is 

 somewhat longer than the others ........ 9 



9 (8) Antennal scape about three quarters as long as an eye or slightly more. 



Length 2-3 mm. Head in dorsal view with temples slightly more than one 

 quarter as long as eyes ..... mustela (Walker) (p. 161) 



- Antennal scape nearly or quite as long as an eye. Length 2-5 to 4 mm. . 10 



10 (9) Head in dorsal view with temples about half as long as eyes, subparallel for a 



short distance behind the eyes. Scutellar frenum marked off by a rather 

 strong impressed line. Length three to four mm. (Amurland) 



nobilis (Walker) (p. 161) 



- Head in dorsal view with temples about one third as long as eyes, converging 



slightly even immediately behind the eyes. Length 2-5 to 3-3 mm. 

 (Europe) ....... brevicornis Thomson (p. 161) 



11 (6) Fore wing with apex of basal cell with a patch of several hairs. Pronotal 



collar slightly margined anteriorly ; behind this with a broad, shiny and 

 weakly-sculptured strip ..... aenea (Walker) (p. 164) 



- Fore wing with apex of basal cell bare or with only a very few hairs. Pronotal 



collar rounded off anteriorly, reticulate with at most a very narrow shiny 



strip along its hind margin ..... circulus (Walker) (p. 163) 



(Males) 



1 Malar space slightly greater than transverse diameter of eye, and fully three 



quarters as long as an eye. Vertex slightly elevated in middle, behind the 

 ocelli ; temples more than half as long as eyes. Maxillary stipites very 

 large. Median area of propodeum strongly reticulate. Gastral petiole as 

 long as or (usually) slightly longer than broad, reticulate 



smaragdina (Curtis) (p. 159) 



- Malar space at least slightly less than transverse diameter of eye. Vertex not 



distinctly elevated behind ocelli ; temples one quarter to slightly more 

 than half as long as eyes. Maxillary stipites large or small. Median area of 

 propodeum sometimes weakly reticulate or smooth. Petiole sometimes 

 transverse ............ 2 



2 (1) Thorax i-8 to 2 times as long as broad, somewhat flattened ; scutellum in 



profile appearing flat or virtually so. Maxillary stipites very small, 

 virtually unmodified. Median area of propodeum strongly reticulate and 

 relatively dull ....... collaris (Walker) (p. 159) 



- Thorax less elongate, more arched dorsally ; scutellum in profile appearing at 



least slightly convex. Maxillary stipites large or small. Median area of 

 propodeum sometimes shiny and weakly sculptured .... 3 



3 (2) Gastral petiole slightly longer than broad, reticulate, with three to six hairs on 



each side, the sides nearly parallel. Antennae with funicular segments, 

 except the sixth, slightly longer than broad. Median area of propodeum 

 with distinct reticulation. Maxillary stipites rather small 



patellana (Dalman) Thomson (p. 160) 

 Gastral petiole usually bare at the sides ; rarely with one or two hairs, in 

 which cases the petiole is either transverse, or else subconical and nearly 

 smooth. Antennae either with all funicular segments quadrate or trans- 

 verse ; or with at most the proximal segments slightly longer than broad. 

 Median area of propodeum more shiny, with weaker reticulation, or mainly to 

 entirely smooth ........... 4 



