Megachile (Megachile) nivalis Friese|
Megachile nivalis Friese, 1903. Ztchr. System. Hym. Dipt. 3, p. 246. ♀. (♂ misdet.)
Megachile (Anthemois) santiarnensis Mitchell, 1934. Amer. Ent. Soc. Trans. 59, p. 311. ♀
Megachile (Anthemois) nivalis Mitchell, 1935. Amer. Ent. Soc. Trans. 61, p. 174.
Megachile (Anthemois) nivalis Mitchell, 1942. Pan-Pacific Ent. 18, p. 115. ♂ ♀
Although the female of this species is easy to recognize, it is very similar to relativa and in most characters is hardly distinguishable from that species. Tergum 6 in the female is straight in profile, with no erect hairs visible, although in the dorsal view a few black erect hairs may be seen toward the sides at base. Also this plate is entirely black pubescent, with no yellowish or golden tomentum at all evident. The scopal hairs on sterna 5 and 6 are entirely black, with the remainder of the scopa yellow as in relativa. In all other essential characters, allowing for individual variations, it agrees with relativa. The male, also, appears to agree with relativa and in fact cannot be separated from it. A few males have been collected under circumstances which would suggest their relationship to female nivalis. These have been studied and compared quite fully with relativa males, in the hope of finding some constant and reliable difference, but without success. It is possible of course that the true male has not yet been discovered.
DISTRIBUTION—Alaska to Idaho, Colorado, Minnesota, Quebec and Maine, June to August.
FLOWER RECORDS — Eleagnus and Taraxacum.