850 M. W. R. de V. GRAHAM 



Britain, France, Spain, Sweden, Germany, U.S.A. 



Biology. Virtually nothing appears to be known of the biology of megacephalus. 

 When first describing it, Fabricius (1793 : 103) mentioned that it had been found 

 in old wood (" Habitat in Daniae ligno antiquo Dom. Lund "). Walker (1833 : 368) 

 stated that it had been taken " on palings ; near London ", and Stephens (1846 : 8) 

 says " Found occasionally on new palings near London ". On 29. vi. 1958 I captured 

 two females of megacephalus indoors, in a window of my house in Oxford ; and on 

 6.vi.i96o I watched a female walking slowly about the wooden gate of our garden, 

 and investigating cracks in its surface. Imagines appear in June and July., 



Mercet (1924) gave good figures of the head, and the female, of megacephalus. 



COLOTRECHNINAE 



Colotrechninae contains a single genus Colotrechnus, whose precise affinities are 

 rather difficult to decide. It was originally placed by Thomson (1878 : 46) in a 

 subtribe Colotrechnides of his tribe Pteromalina [most of his subtribes are roughly 

 equivalent to the subfamilies recognized in the present work]. Ashmead (1904 : 

 281, 285) put it in Cleonymidae and established for it a subfamily Colotrechninae, 

 although the genus was in fact known to him only from Thomson's description. 

 Schmiedeknecht (1909 : 270, 289) made it a tribe Colotrechnini of the Miscogaster- 

 inae. In his key to the Czechoslovak Pteromalidae, Boucek (in Peck el al., 1964 : 

 41) placed Colotrechnus in a subfamily Colotrechninae. I agree with the latter view. 

 When compared with the other subfamilies of Pteromalidae, Colotrechninae appear 

 to me to be nearest Pteromalinae, from which they differ chiefly in the characters 

 given in my key to subfamilies. The forward position of the axillae and the shape 

 of the scutellum in Colotrechnus do not occur in other Pteromalids, but rather 

 resemble these structures in some Eulophidae. 



COLOTRECHNUS Thomson 



Colotrechnus Thomson, 1878 : 46. Type-species : C. subcoeruleus Thomson by monotypy. 



Colotrechnus Thomson ; Schmiedeknecht, 1909 : 289. 



Zanonia Masi, 192 1 : 184-186. Type-species : Z. viridis Masi by monotypy. 



Colotrechnus Thomson ; Nikol'skaya, 1952 : 209. 



Colotrechnus Thomson ; Delucchi, 1956a : 233-237. 



Colotrechnus Thomson ; Peck et al., 1964 : 41—42. 



Zanonia Masi was placed in synonymy with Colotrechnus Thomson by Delucchi 

 (1956a : 233), who revised the European species. Burks (1958 : 13-14) is not sure 

 whether this action is justified but tentatively regards Zanonia as being of 

 subgeneric rank. Personally I do not think that the differences between the 

 respective type-species are of generic value. 



Key to European Species 



(Females) 



1 Antenna with segments of funicle longer than broad, or at most the distal segments 

 quadrate. Disc of fore wing usually with a yellowish or brownish cloud. Body 



