Ottawa (Dunrobin), ON Canada

22 July 2001   11:44PM EST  (left)
20 July 2002   10:29PM EST  (right)

Resting specimens of Clostera apicalis characteristically hold their wings close to and almost rolled around their bodies, as in both photos above, and I have not yet succeeded in photographing a specimen with its wings in a flatter, more open position.  Looking sideways at the moth at rest, however, you can still see an obvious white squiggle of the postmedial line just below the costal edge of the forewing, with shades of rusty brown around it.  The middle of the forewing has an oblique whitish line crossing from the "top" of the medial area at the costa, down to meet the postmedial line at the inner margin, quite unlike the lines on the forewing of Clostera albosigma (7895), which also occurs in my area.

According to Handfield (1999), the larvae of Clostera albosigma generally feed on willow, poplar and birch species, and often form communal nests of silk.  There are two generations, in late spring and summer, in my area.

I have only photographed this species twice in three years: in 2001 on 22 July; in 2002 on 20 July.