306 M. W. R. de V. GRAHAM 



o*. Differs from that of fulvicoxis as follows : 



Anterior margin of clypeus almost angulate medially. Combined length of pedicellus and 

 flagellum hardly as great as breadth of head ; funicular segments slightly shorter, the first 

 distinctly shorter than the pedicellus and only 1-4 to i-6 times as long as broad. 



Holotype $. England : Suffolk, 1930, bred from Rhabdophaga sp. on Salix 

 triandra L. (H. J. Barnes), in BM(NH). 



Paratypes. Same data as holotype, 3 $, 1 $, in BM(NH). 



Gastrancistrus longigena sp. n. 



(Text-fig. 239) 



$. Differs from that of fulvicoxis sp. n. as follows : 



Antennal scape rather more extensively infuscate apically ; coxae black with a metallic 

 tinge, or at most the distal third of the fore coxae is yellowish ; all the femora more or less 

 infuscate proximally, at least with a dark stripe or mark beneath ; all tibiae, except their bases 

 and tips, reddish, the mid and hind ones sometimes slightly infuscate medially ; wing venation 

 somewhat darker, the parastigma, base and apex of the marginal vein, the stigmal vein and the 

 stigma, brown. Length 1-9 to 2-6 mm. 



Body less elongate, much as in salicis (Nees). Head in dorsal view 1 -9 to 2 times as broad as 

 long ; temples converging slightly behind the eyes. Eyes nearly circular, separated by 1-31 to 

 1-35 times their own length. Malar space nearly or quite two thirds the length of an eye. 

 Breadth of oral fossa 1-5 to 1-7 times the malar space. Clypeus only about i-6 times as broad 

 as long, alutaceous, except sometimes its anterior margin. Antenna (Text-fig. 239). Head and 

 thorax with rather weaker sculpture, hence rather more shiny. Dorsellum weakly alutaceous, 

 shiny. Speculum of fore wing, on the upper surface of the wing, open below except sometimes 

 proximally. 



Gaster ovate, as long as or somewhat longer than the thorax, but shorter than head plus thorax, 

 1 -8 to 2 -3 times as long as broad. 



o". Unknown. 



The female of G. salicis (Nees), as interpreted here, differs from that of longigena 

 in its rather more transverse head, 2-15-2-3 times as broad as long ; slightly oval 

 eyes, 1-15-1-2 times as long as broad ; rather shorter malar space, half the length of 

 an eye or slightly more ; broader oral fossa, which is 1 -9-2 -5 times the malar space ; 

 and broader clypeus, which is nearly or quite twice as broad as long. The speculum 

 of the fore wing in salicis is closed or nearly closed below on the upper surface of 

 the wing. 



Holotype $. England : Oxfordshire, Marston Ferry, near Oxford, 13^.1961, 

 swept from foliage of Salix purpurea L. (Graham), in Hope Department, University 

 Museum, Oxford. 



Paratypes. Same locality as holotype, 2 $, n.v.1961, 4 $, 13^.1961, swept from 

 foliage of Salix purpurea L. (Graham) ; Berkshire, Wytham, 2 $, 24.V.1961, swept 

 from foliage of Salix viminalis L. (Graham), in Graham collection. 



Biology. Unknown. 



