PTEROMALIDAE OF N.W. EUROPE 629 



Cecidomyiidae or (occasionally) other insects. Five of the species are associated 

 mainly with spruce (Picea), one with larch (Larix). 



Key to European Species 

 (Females) 



1 Upper subtriangular area of mesepisternum, below base of hind wing, more 



weakly sculptured and more shiny than the rest of the mesopleuron, with 

 delicate engraved reticulation, or partly smooth. Antennal formula 



U353orii263 .2 



Entire mesopleuron relatively dull, with strong reticulation which is slightly 



raised above the general surface. Antennal formula 11353 . • 5 



2 (1) Lower edge of antennal toruli below the level of the ventral edge of the eyes ; 



antennal formula 11353 ; combined length of pedicellus and flagellum 

 virtually equal to breadth of head ; funicular segments slightly longer than 

 broad, or at most the distal segments quadrate. Frons with numerous 

 distinct piliferous punctures amongst the reticulation hungaricus (Erdos) (p. 630) 

 Lower edge of antennal toruli at or slightly above the level of the ventral edge 

 of the eyes ; antennal formula 11353 or 11 263 ; combined length of pedi- 

 cellus and flagellum less than breadth of head ; proximal segments of 

 funicle quadrate to slightly transverse, distal segments at least slightly 

 transverse. Frons with less numerous and less distinct piliferous punctures 3 



3 (2) Ovipositor sheaths strongly exserted, to a length at least slightly more than 



one third that of the hind tibia. Antennal formula 11353 



strobilorum Thomson (p. 630) 



- Ovipositor sheaths only slightly exserted. Antennal formula 11353 or 11263 4 



4 (3) Antennal formula 11353. Combined length of dorsellum and propodeum, in 



the median line, about two thirds that of the scutellum. Antennae and legs 

 fuscous, only the knees, apices of tibiae, and bases of tarsi pale 



laricis Boucek (p. 631) 



- Antennal formula 11263. Combined length of dorsellum and propodeum only 



about half that of the scutellum. Antennal scape normally more or less 

 testaceous, legs relatively paler than in laricis 



hohenheimensis (Ratzeburg) (p. 631) 



5 (1) Gaster 1-3 to 1-5 times as long as head plus thorax, 2 to 2-5 times as long as 



broad. Fore wing with marginal vein about twice as long as the stigmal 

 vein ; postmarginal vein shorter than the marginal. Legs darker ; femora, 

 and sometimes the tibiae, extensively darkened . piceae (Ruschka) (p. 632) 



- Gaster not or only slightly longer than head plus thorax, 1-5 to i-8 times as 



long as broad. Fore wing with marginal vein about 1-7 times as long as 

 the stigmal vein ; postmarginal vein hardly shorter than the marginal. 

 Legs paler ; femora and tibiae testaceous, or only the hind femora darkened 



vala (Walker) (p. 632) 



(Males) 



1 Upper subtriangular area of mesepisternum, below base of hind wing, more 



weakly sculptured and more shiny than the rest of the mesopleuron, with 

 delicate engraved reticulation, or partly smooth. Genae curved as seen in 

 frontal view of head. Either the antennal formula is 11263 ; or the lower 

 edge of the toruli is below the level of the ventral edge of the eyes . . 2 



- Entire mesopleuron relatively dull, with strong reticulation which is slightly 



raised above the general surface. Genae, in frontal view of head, appearing 

 prominent or angulate just above the bases of the mandibles. Antennal 



