no. 3644 TIPHIIDAE — KROMBEIN 5 



and posterior surfaces, lateral surface pitted as are the dorsal and 

 posterior. 



Abdomen slender, 7-segmented ; disk of first tergum ridged ante- 

 riorly; last dorsal segment convex, without differentiated pygidial 

 area, its apex not notched for reception of the recurved hypopygial 

 aculeus as in Mesa. 



Genitalia very similar in conformation to those of Mesa except 

 that the lamina volsellaris is much better developed, extending to 

 or almost to apex of cuspis volsellaris. 



Wings reaching nearly to apex of abdomen; anterior margin of 

 marginal cell confluent anteriorly with costal margin of wing, nar- 

 rowly rounded apically; three submarginal cells, the second and third 

 each receiving a recurrent nervure; cubitus in hind wing arising 

 before transverse median nervure. 



Legs rather short, mid- and hind tibiae lacking the scattered spines 

 found in Mesa; hind coxa carinate along inner margin above; tarsal 

 claws cleft. 



Color as in female, but basal flagellar segments of antenna usually 

 red, and wings frequently less infumated. 



Key to Species and Subspecies of Hylomesa 



(The males are unknown in t. tricolor and ugandensis; females are unknown in crassepunctata and 



dimidiaticornis.) 



1. Females; abdomen with six visible segments, antenna apparently only 11- 



segmented because of the nearly entirely recessed pedicel 2 



Males; abdomen with seven visible segments, antenna apparently only 

 12-segmented because of the recessed pedicel 7 



2. Apex of hind tibia on inner surface with four stout, short, flattened setae; 



distance between hypostomal and occipital carinae only half the length of 



hypostoma 3 



Apex of hind tibia without such setae; distance between hypostomal and 

 occipital carinae subequal to length of hypostoma 5 



3. Posterolateral angle of head angulate beneath; clypeal keel very strongly 



produced, nasiform as viewed from side; inferior margin of hind femur 

 obtusely angulate at middle; Borneo, Sumbawa, Burma. 



shuckardi (Turner) 



Posterolateral angle of head rounded beneath; clypeal keel distinct but not 



so produced; inferior margin of hind femur rounded . . tricolor (Smith) . 4 



4. Clypeal keel rather weak, present only on basal two-thirds; median teeth on 



clypeal margin weaker; pronotal ridge weaker, the disk with more dis- 

 persed punctures; anterior ridge on first tergum weaker; Borneo. 



tricolor tricolor (Smith) 



Clypeal keel stronger, complete, terminating on apical third in an inverted 



U-shaped carina the arms of which extend to the strong marginal teeth; 



pronotal ridge stronger, the punctures more crowded on anterior half of 



disk; anterior ridge on first tergum stronger; Java. 



tricolor lieftincki, new subspecies 



