PTEROMALIDAE OF N.W. EUROPE 307 



Gastrancistrus coactus sp. n. 



(Text-figs. 235, 236) 



$. Colour as in salicis (Nees) but the body tends more towards blue-green or blue ; scape 

 often extensively infuscate with a metallic tinge, sometimes wholly so, or pale at the base only ; 

 femora tending to be darker, their proximal half to two thirds black ; tibiae often more or less 

 broadly brown to blackish medially. 



Structurally differs from salicis as follows ; 



Head in dorsal view (Text-fig. 236) less transverse, i-8 to 2 times as broad as long, shaped 

 much as in fulvicoxis, with the temples hardly converging behind the eyes. Eyes 1-2 to 1-35 

 times as long as broad, separated by 1 • 15 to 1 -25 times their own length. Malar space variable, 

 from slightly less than half to slightly more than half the length of an eye. Anterior margin 

 of clypeus (Text-fig. 235) gently curved or occasionally almost truncate. • Antennae similar to 

 those of longigena sp. n. (Text-fig. 239) ; pedicellus about as long as anelli plus first funicular 

 segment or even a little more ; first funicular segment subquadrate, the following segments 

 at least very slightly transverse ; clava as long as, or somewhat longer than, the three preceding 

 funicular segments together. 



Scutellum usually with three, occasionally four, rarely five, pairs of bristles. Propodeum 

 medially approximately one third the length of the scutellum ; median carina more or less 

 indicated but not sharp ; callus with four to six bristles. Fore wing with speculum open or 

 closed. 



Gaster ovate, 1 -8 to 2 -3 times as long as broad, about as long as or a little longer than the thorax. 



o*. Unknown. 



Holotype 9. England : Buckinghamshire, Hell Coppice, near Oakley, 2.VL1953, 

 from Salix cinerea L. (Graham), in Hope Department, University Museum, Oxford. 



Paratypes. Same data as holotype, 1 $ ; Berkshire, Wytham, 2 $, 2.vi.i96i, 

 swept from Salix (cinerea L. or caprea L.) (Graham) ; Huntingdonshire, Woodwalton 

 Fen, 1 $, g.vi.1953, from Salix sp. (Graham), in Graham collection. Scotland : 

 West Inverness, Arisaig, 1 $, 5.vii.ig6i, swept from Salix aurita L. (Graham), in 

 Graham collection : Ireland : West Donegal, Sessiagh or Kill Lough, 1 $, 10. vi. 1955 

 (A. W. Stelfox), in Graham collection. 



Biology. Unknown. 



Gastrancistrus praecox sp. n. 



(Text-figs. 232, 238) 



Semiotus fulvicornis Walker, 1874 : 316, $ [secondary homonym of Lamprotatus fulvicornis 

 Walker, 1874 : 315,6*]- 



$. Colour as in salicis (Nees) ; tibiae sometimes heavily infuscate. Length i-8 to 2-1 mm. 



Structurally differs from salicis as follows : 



Head in dorsal view (Text-fig. 238) very slightly less transverse (breadth : length 1-95 to 2). 

 Eyes separated by 1 -i to 1-2 times their own length. Antennae with funicle rather more slender 

 proximally, its first segment not stouter than the pedicellus in profile, sometimes even rather 

 less stout, the flagellum therefore appears more distinctly clavate than in salicis ; clava slightly 

 longer, its length equalling 3 to 3-5 of the preceding funicular segments ; sensilla of flagellum 

 less numerous. 



Each posterior ocellus is separated by 1-3 to 1-4 times its own major diameter from the 

 adjacent eye ; POL 1-75 to 2 OOL. 



