1986] Wiggins & Richardson — Onocosmoecus 203 
fused to the lateral lobes, demonstrating a tendency for variation 
similar to that which is so widespread among Nearctic specimens. 
All four male specimens are generally consistent in genitalic charac- 
ters with the external branches of segment X expanding rather 
broadly at mid-length and tapering toward a rounded apex, but this 
condition also occurs widely in Nearctic material; two of the speci- 
mens have four spines on each paramere, but the Dalneje Lake male 
shows three and five spines respectively on each paramere, and the 
Chishima male five and six spines. The fore wings of the syntype 
female have dark corneous points surrounded by faint darkish areas 
of moderate size, similar to the type specimens of the Nearctic O. 
occidentis, alascensis, and coloradensis; and these darkish areas are 
somewhat variable in size in the other specimens. The few specimens 
we have seen are smaller [length of fore wing male 14.5-16 mm (n = 
4), female 15-17.5 (n = 2)] than most of our North American spec- 
imens, although specimens of that size are represented in our mate- 
rial. Finding no characters to separate these representatives of O. 
flavus from the Nearctic populations of O. unicolor , we extend our 
interpretation of O. unicolor as a widespread and highly variable 
species to include the Palaearctic O. flavus. 
Other variants. One of the extreme variants encountered occurs 
in Alaska (Admiralty Island, Young Bay, 23 July 1981, 1<5, 1?, 
ROM). The male of this series (Fig. 4) shows both pronounced 
narrowing at the base of the external branch of segment X and 
broadening toward the apex, as well as a strong tooth on the mesal 
edge of the basal segment of the inferior appendage (Fig. 4b). In the 
female (Fig. 5), segment X forms a slender tubular ovipositor lack- 
ing any dorsomedian subdivision, and the basal shoulders of X are 
not produced as a ledge. By contrast, in a female from Oregon 
(Baker Co., Pine Cr., 14 July 1967, 1<5, 1?, ROM), segment X has 
the form of a slender ovipositor (Fig. 6), but the base of X is 
strongly produced as a sharp dentate ledge. While these are repre- 
sentative of the extreme variation, we found intermediates between 
them and less extreme genital structures. In a single series from 
Oregon (Lane Co., 12 mi. SE Eugene, 22 Sept. 1968, 2(5, 2?, ROM) 
segment X in ventral aspect of one female forms an elongate ovi- 
positor similar to that in Figure 5, but in the other female the ovi- 
positor is extremely wide; in one of these females the lateral vulval 
lobes are enlarged apically into a thick truncate knob, very unlike 
the more usual flattened condition in Figure 3b. 
