62 



10 (5) Intermediate tibiae with a distinct calcar. 



1 1 (28) Thorax or abdomen or both with red markings. 



12 (13) Basal abdominal segment entirely red above, or at most a little 



infuscate, second also largely red as also the tegulae. 



Odynerus frater. 



13 (12) Basal abdominal segment black with a red hind-margin. 



14 (15) Prothorax and mesopleura without red spots (female). 



O. paludicola. 



15 (14) Prothorax and mesopleura marked with red. 



16 (21) Second ventral segment very strongly and abruptly raised 



behind the transverse sulcature to a height much greater 

 than that of the basal part of the segment. 



17 (20) Red colour of pronotum extended back along its margin to 



reach the tegulae. 



18 (19) Second ventral segment very strongly raised from the costae; 



clypeus of male red at base; mesonotum of female more 

 finely and irregularly punctured. O. leiodemas. 



19 (18) Second ventral segment still more strongly raised from the 



sulcature ; clypeus of the male not red at the base ; mesono- 

 tum of female more strongly and evenly punctured. 



O. pseudochromoides , sp. nov. 



20 (17) Red markings of pronotum not extended back along the margin 



to touch the tegulae. O. pseudochromus. 



21 (16) Second ventral segment not very greatly and abruptly raised 



behind the costae; at most it is raised to a height about 

 equal to the basal part of the segment in front of the costae. 



22 (23) Mesonotum with irregular puncturation, consisting of sparse 



larger punctures (which are themselves not at all coarse) 

 and finer interstitial punctures; wings shining fuscous. 



O. paranoias, sp. nov. 



23 (22) Mesonotum with very dense and uniform puncturation, or if 



the punctures are not so dense they are deep and coarse. 



Wings to a large extent subhyaline. 

 Propodeum rugose or rugosely punctate. 



Mesonotum with red lines. O. homoeophanes. 



Mesonotum black. O. eucharis. 



Propodeum smooth, with some shallow punctures. O. oahuensis. 

 Thorax and abdomen without red markings, rarely with the 



apical margins of one or more abdominal segments very 



narrowly and indistinctly testaceous. 

 One or more entire yellow or whitish bands on the abdomen 



(thorax also often with yellow markings). 

 Mandibles in both sexes entirely or almost entirely red (male 



with the clypeus very deeply emarginate at the apex, that 



of the female distinctly but less deeply). O. xerophilus. 

 31 (30) Mandibles at most red or piceous on the apical half; generally 



for the most part black. 



