PTEROMALIDAE OF N.W. EUROPE 603 



Anterior margin of clypeus normally (Text-fig. 468) with a median tooth and a 

 projection on either side of it, in runts of muscarum the lateral projections 

 may be virtually absent, but this species has the antennal scape nearly as 

 long as an eye and reaching slightly above the vertex .... 2 



2 (1) Gaster conical, acuminate, much longer than head plus thorax, 3 to 3-7 times 



as long as broad ; last tergite 2 to 2-5 times as long as its basal breadth ; 

 ovipositor sheaths distinctly exserted. 



Antennal clava with its sutures not oblique ; tuft of micropilosity on its 

 third segment small, extending over at most about one third the length of 

 the clava ; fourth funicular segment quadrate . oxygyne (Walker) (p. 607) 



Gaster ovate to lanceolate-ovate, not longer than head plus thorax, at most 

 about 2-5 times as long as broad ; last tergite at most slightly longer than 

 its basal breadth .......... 3 



3 (2) Fourth funicular segment of antenna distinctly elongate, usually about 1-3 



to 1 -5 times as long as broad ; fifth usually slightly elongate, sixth most 

 often quadrate or very slightly elongate ; combined length of pedicellus and 

 flagellum usually distinctly greater than the breadth of the head . . 4 



Fourth funicular segment of antenna, often also the third, quadrate to 

 slightly transverse ; fifth and sixth more or less transverse, sometimes 

 about 1 -5 times as broad as long ; combined length of pedicellus and 

 flagellum, except in some micans, not greater than the breadth of the head 6 



4 (3) Temples, in dorsal view of the head (Text-fig. 470), converging only slightly 



behind the eyes, slightly more than one third as long as the eyes. Malar 

 space slightly more than half the length of an eye. Large species, 3-8 to 

 5-3 mm. ........ liparae (Giraud) (p. 607) 



Temples converging quite strongly behind the eyes (Text-figs. 471-474), less 

 than one third as long as the eyes. Malar space rarely so long. Size 

 usually less ........... 5 



5 (4) First funicular segment 1-4 to 1-7 times as long as the pedicellus, 2-2 to 2-6 



times as long as broad ; flagellum fusiform or clavate, fairly stout 



laticeps (Walker) (p. 607) 



- First funicular segment at most slightly longer than the pedicellus and at 



most twice as long as broad ; flagellum only feebly clavate . . . 10 



6 (3) Antennal clava with the dividing lines between its segments oblique as seen in 



profile, the patch of micropilosity (Text-fig. 475) larger and extending about 



half way along the clava ......... 7 



- Antennal clava with the dividing lines between its segments not or hardly 



oblique, the patch of micropilosity (Text-figs. 476, 477) smaller and 

 extending over at most slightly more than one third the length of the clava 10 



7 (6) Third funicular segment (Text-fig. 478) slightly to distinctly elongate, 



except in small specimens. Temples (Text-fig. 471) about one quarter as 

 long as the eyes. Malar space 0-44 to 0-47 the length of an eye. Basal vein 

 of fore wing usually bare, in one specimen with a single hair. Large species, 

 3-1 to 4-8 mm. Head and thorax not dark blue or bluish black ; only the 

 fore and mid femora more or less infuscate . . fervida Graham (p. 608) 



- Third funicular segment usually quadrate, rarely very slightly elongate. 



Temples (Text-fig. 472) about one fifth as long as the eyes. Malar space 

 0-37 to 0-4 times the length of an eye. Basal vein of fore wing bare or with 

 one to nine hairs; in favorinus, which often has the basal vein bare, the head 

 and thorax are dark blue to bluish black and all the femora are mainly black. 

 Species usually smaller ( 1 -9 to 3-9 mm.) ...... 8 



8 (7) Head and thorax dark blue to bluish black. Postmarginal vein of fore wing 



not, or only slightly, shorter than the marginal vein, the latter 1-65 to 1-85 



