PTEROMALIDAE OF N.W. EUROPE 401 



nucha represented merely by a sharply-defined transverse ridge 



STAUROTHYREUS Graham (p. 699) 

 Median area of propodeum relatively dull, uniformly reticulate ; costula often 

 straight ; nucha more or less developed though not very clearly defined 

 anteriorly, reticulate .......... 101 



101 (100) Propodeum medially at least somewhat more than half as long as the scutel- 



lum ; costula straight or nearly so, if not quite straight, then the median 

 length of the propodeum is about two thirds that of the scutellum 



ABLAXIA Delucchi (p. 572) 



- Propodeum medially about half as long as the scutellum ; costula not quite 



straight, often weak, especially in the middle APELIOMA Delucchi (p. 582) 



102 (99) Antennae with usually both anelli, occasionally only the second anellus, 



quadrate ; the anelli very conspicuous, their combined length at least 

 somewhat more than half that of the first funicular segment (Text-figs. 

 518, 520, 521). POL much greater than OOL. 



Propodeal nucha represented only by a narrow, transversely lunate 

 strip, which is weakly sculptured . . . . . . .103 



- Antennae with both anelli usually moderately to strongly transverse ; if 



only slightly transverse, then POL is only about equal to OOL . . 104 



103 (102) First funicular segment of antennae not longer, and often shorter, than the 



sixth segment, and usually shorter than the second segment. Pronotal 

 collar with at most a weak irregular marginal carina. Hairs of vertex, 

 mesoscutum, and scutellum sometimes dark 



MESOPOLOBUS Westwood (p. 683) 

 First funicular segment slightly to much longer than the sixth segment, and 

 as long as, or slightly longer than, the second segment. Pronotal collar with 

 a strongly raised, very sharp front margin, except in one species which has 

 the hairs of the vertex, mesoscutum, and scutellum pale 



EUMACEPOLUS Graham (p. 633) 



104 (102) Propodeal nucha represented only by a ridge ; or a narrow transverse strip 



which is weakly aciculate (transversely) or smooth, and is usually defined 

 anteriorly by a sharp edge . . . . . . . . .105 



- Propodeum with a convex reticulate nucha which occupies at least about one 



third of the median length of the propodeum, and is not, or not very sharply, 

 defined anteriorly . . . . . . . . . .144 



105 (104) Postmarginal vein of fore wing only slightly longer than the stigmal vein . 106 



Postmarginal vein obviously longer than the stigmal vein .... 109 



106 (105) Fore wing (upper surface) with a broad bare strip below the marginal vein, 



extending right to the stigmal vein ; on the lower surface of the wing this bare 

 strip is interrupted only by a few scattered hairs ; disc of wing rather 

 sparsely pilose. Head protuberant at level of antennal toruli. Posterior 

 half of mesosternum clothed with long whitish hairs which stand out nearly 

 at a right angle to the surface . . CONOMORIUM Masi (p. 821) 



- Fore wing with at most a narrow bare strip below the marginal vein ; if 



such a strip is present, then the disc of the wing is not sparsely pilose, 

 the head is not protuberant at the level of the antennal toruli, and the hairs 

 of the mesosternum are not strongly outstanding . . . .107 



107 (106) Posterior half of mesosternum clothed with strongly outstanding whitish hairs 



ERDOESINA Graham (p. 796) 



- Posterior half of mesosternum with hairs only slightly outstanding . . 108 



108 (107) Antennal toruli much nearer to the anterior margin of the clypeus than to the 



median ocellus, their lower edges not or hardly above the ventral edge of the 

 eyes. Head somewhat protuberant at level of toruli. the face distinctly 



