Ottawa (Dunrobin), ON Canada

5 May 2003   9:28PM EST  (top left)
14 April 2005   9:30PM EST  (top right)
19 April 2005   8:53PM EST  (bottom left)
18 April 2004   10:10PM EST  (bottom right)

Orthosia rubescens, also known as the Ruby Quaker, is one of five species of Orthosia that have been recorded from the Ottawa area (J.D. Lafontaine, pers. comm., 2001), all of which are illustrated on this website.  Several of these species are quite variable in appearance, an issue complicated by the frequent occurrence of worn specimens and the propensity of the forewing color and pattern to be obscured by reflections from flash photography. My thanks to Dr. J. Donald Lafontaine and Mr. J.T. Troubridge of Agriculture Canada for their patience and forbearance in identifying a number of specimens that I found confusing, including the one pictured at top right.

Orthosia rubescens has a tan forewing shaded, sometimes heavily, with reddish brown. The antemedial and postmedial lines are generally obscure, but there may be some evidence of the subterminal line as a somewhat irregular tan line a short distance inside the outer margin, as in the two photos at top.  The orbicular and reniform spots are sometimes well marked with a tan outline that contrasts sharply with the reddish brown shading around them.  Both spots have reddish brown filling, and the reniform spot has very dark filling in its lower end.  As can be seen in the bottom photos, however, these spots are not always clearly marked.  Generally, the furry-appearing thorax is reddish or orangish brown, with little suggestion of gray as in some other Orthosia species.  The hindwing is grayish brown with a pale fringe.  Covell (1984) indicates a wingspan ranging from 3.0 to 4.0 cm for this species.

According to Handfield (1999), the host plants reported for Orthosia rubescens include red oak, maple, several species of cherry, poplar and beech. For my general area, he indicates an adult flight season from about mid-April into early June.  Covell (1984) notes that adults may fly in warm periods during winter, presumably in more southerly locations than Ottawa.

My records to date for Orthosia rubescens (each date representing "the night of", and excluding those for which I am not confident of the identification) are in the table below: