FLIES OF THE GENUS OGCODES — SCHLINGER 



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both sexes occurred in this area was less than two months. Some of 

 the females collected by Bechtel laid eggs in large gallon jars. These 

 eggs were kept in the laboratory at 80 percent humidity and 85° F., 

 but no larvae emerged. Apparently the one-day trip of some 24 

 hours without proper humidity-temperature control was enough to 

 desiccate 100 percent of the eggs. The first-instar larva of this species 

 is still unknown. 



Specimens of this species were reported by Bechtel and Schlinger 

 (1957) as larval provisions in the nests of a crabronid, Ectemnius 

 (Hypocrabro) spiniferus Fox, near Sacramento, Calif. 



Discussion: An examination of the male holotype (Wyoming) and 

 the two male paratypes (Kansas) of albicinctus Cole, together with a 

 large series of eugonatus (about 250 specimens) from throughout its 

 range, indicated that albicinctus is merely a low-frequency color 

 variant of eugonatus. Furthermore, Cole (1919) admittedly did not 

 know eugonatus when he described albicinctus (as marginatus Cole). 

 Further evidence to support this synonymy is given by the series of 

 specimens from Morongo Valley, Calif., in which there were examples 

 of both color forms. Also, when the male genitalia of typical eugonatus, 

 typical albicinctus, and typical melampus Loew were examined in 

 series, the slight differences noted by Sabrosky (1948) were found to 

 occur in each of the so-called species with about the same frequency. 

 0. melampus will probably be found to be a melanic color variant of 

 eugonatiLS when more specimens can be studied (see discussion under 

 melampus). The probable relationship of eugonatus to the Nearctic 

 species is shown in text figure 3. 



Figure 5.— Distribution of Ogcodes eugonatus Loew (solid circles) and 0. melampus Loew 

 (open circles) in the United States, 



