PTEROMALIDAE OF N.W. EUROPE 287 



marginal vein, tending to narrow distally, and not always reaching the 

 stigmal vein. Ovipositor sheaths sometimes less far exserted ... 54 



54 (53) Gaster including ovipositor sheaths longer than head plus thorax ; exserted 

 portion of ovipositor sheaths, in profile, from slightly more than half as long, 

 to as long as, the hind tibia. Marginal vein of fore wing (Text-fig. 267) 2-3 

 to 2-95 times as long as the stigmal vein . . glabellus (Nees) (p. 323) 



Gaster including ovipositor sheaths nearly or just as long as head plus thorax ; 

 exserted portion of ovipositor sheaths, in profile, from one quarter, to about 

 two fifths, as long as the hind tibia. Marginal vein 2-8 to 3-3 times as long 

 as the stigmal vein ......... sp. indet. 



The FUSCICORNIS-Group 

 Gastrancistrus fuscicornis Walker 



Gastrancistrus fuscicornis Walker, 1834 : 171, <J. 

 ? Tridymus Aphidum Ratzeburg, 1848 : 183, $. 



Type material. Gastrancistrus fuscicornis Walker. Syntypes, 2 <$. LECTO- 

 TYPE, the second specimen, bearing a Waterhouse label. 



Tridymus aphidum Ratzeburg. Types presumed lost. Hartig's collection (Munich) 

 contains 3 $ of Gastrancistrus fuscicornis mounted with some rose-leaves bearing the 

 skins of parasitized aphids, from which the Chalcidoids were evidently reared. 

 These are the only Gastrancistrus known to me which have been reared from aphids, 

 and as they agree well enough with Ratzeburg's description of Tridymus aphidum 

 they may be taken as an indication of the identity of that species. It might even 

 be convenient to select one of the Hartig specimens as neotype of aphidum, 



Britain, Germany ; uncommon. I have swept it from foliage of Quercus and 

 Salix spp. Boucek (1965 : 7) recorded it from Moldavian S.S.R. ; this record is 

 possibly correct but needs checking since fuscicornis is now shown to be one of a 

 complex of species. 



Biology : see above. Imagines July-August. 



Gastrancistrus alectus Walker 

 Gastrancistrus Alectus Walker, 1848 : 105, 158, "<$ " [recte $]. 



$ (redescription) . Body black, with some metallic reflections as follows : head usually olive 

 greenish, sometimes more or less suffused with purplish bronze ; petiole brown or partly 

 testaceous ; base of gaster with rather conspicuous greenish reflections ; mesoscutum, scutel- 

 lum sometimes, axillae, propodeum and disc of gaster, with obscure metallic reflections which 

 vary from olive greenish to purplish bronze. Palpi and mandibles testaceous, the latter with 

 reddish teeth. Scape testaceous, brownish apically ; pedicellus and flagellum fuscous. Legs 

 testaceous, the knees and the mid and hind tarsi slightly paler than the rest ; hind coxae with 

 their basal third or rather more infuscate, fore and mid coxae slightly infuscate basally ; fifth 

 segment of all tarsi fuscous. Tegulae testaceous in front, more brownish posteriorly. Wings 

 hyaline ; venation testaceous. Length 1 to i-6 mm. 



Head 1 -3 to 1 -4 times as broad as the mesoscutum, in dorsal view about 2-2 times as broad as 

 long ; temples very short and receding ; ocelli in a very obtuse triangle whose base is about 2-5 

 times its height, POL about 1-2 OOL. In front view the head (Text-fig. 208) is transversely 



