FLIES OF THE GENUS OGCODES — SCHLINGER 



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and pilation, but no doubt other groups will need to be added when 

 more species can be studied. These species groups, together with 

 typical species, distribution, and total number of presently assignable 

 species, are listed in table 2. 



Table 2.— Species groups of the subgenus Ogcodes Latreille 



The apparent relationships of these species groups are shown in 

 text figure 1. The brunneus group, which is closely related to Pro- 

 togcodes paramonovi, apparently gave rise to the more widespread 

 eugonatus group. However, these two groups are presently widely 

 separated geographically, and this might give the impression that 

 their relationship is superficial. It seems likely that members of the 

 eugonatus group will be found to occur in the Oriental region. Also, 

 it seems likely that more species occur in the Ethiopian and Aus- 

 tralian regions than is known at present, but the absence of material 

 and the lack of adequate descriptions of genitaha and wing venation 

 of the known species from the intervening areas prevent me from 

 assigning many of the known species to this or other species groups. 

 The Holarctic borealis group appears to be a rare, primitive one, 

 which probably gave rise to both the colei and pallidipennis groups, 

 the latter being the most common and widespread group of the 

 subgenus. The colei group is not homogeneous, and might better be 

 divided into two or three groups based primarily on wing venation 

 and structure of the ejaculatory apodeme. However, enough char- 

 acteristics seem to hold tme for all the included species to maintain 

 it as a single varied group at the present time. 



