Ottawa (Dunrobin), ON Canada

11 May 2001   9:33PM EST  (top left)
30 May 2002   9:35PM EST  (top right)
5 May 2002   10:50PM EST  (bottom)

In my general area, three species of Gluphisia are known to occur, of which Gluphisia septentrionis is the most common.  All of these Gluphisia species generally conform to the image of the plain drab gray moth, and the identification of the specimens above was a slow process as I puzzled over the subtle (to an amateur) differences among them.  Moreover, pristine fresh specimens of live moths can sometimes look very different from specimens in collections, which have endured more handling.  This identification is based on careful comparison of photographs of Gluphisia species in Covell, in Handfield, on those moth web sites illustrating these species, and on discussions with Dr. J. Donald Lafontaine of Agriculture Canada; while I am fairly confident that I've correctly identified the specimens illustrated and referred to on this web page, there remain a number of unidentified photographs in my files which might be Gluphisia septentrionis, or possibly other species of Gluphisia.

Covell (1984) has described Gluphisia septentrionis as having a dark gray forewing, with the pattern often obscure.  Illustrations in Handfield (1999) and on the Internet, however, generally show a much paler gray than in my specimens above.  One common feature is the brownish medial area, especially evident near the inner margin of the forewing, and with no distinctive markings.  Another identifiable feature is in the basal area, where the basal line is deeply indented, outlining two brown-filled loops right at the base of the wing.  Covell also refers to whitish antemedial and subterminal areas, which are not evident in the specimens above, although the subterminal area is perhaps a little paler than the rest of the wing.  The top left photo also shows a somewhat indistinct jagged subterminal line in the slightly paler gray subterminal area.

Gluphisia septentrionis is widely distributed and quite common across North America, and is one of the smaller Notodontids, with a wingspan of only 2.5 to 3.3 cm, according to Covell.  The larva feeds on poplar species.  Handfield indicates two generations per season in my general area, with flight seasons from early May through June, and through July through the third week of August.

I have photographed this species in 2001 on 11 May and on 13 and 24 June; in 2002, on 5 and 30 May.