Ottawa (Dunrobin), ON Canada

14 May 2004   9:42PM EST  (top)
15 May 2003   11:03PJ EST  (second from top)
18 May 2004   10:10PM EST  (second from bottom, left)
15 June 2004   10:19PM EST  (second from bottom, right)
8 August 2003   11:32PM EST  (bottom)

Xanthorhoe ferrugata, also known as the Red Twin-Spot, is one of half a dozen species of Xanthorhoe known to occur in the Ottawa area (J.D. Lafontaine, pers. comm., 2001), and the one most commonly observed at my location.

Xanthorhoe ferrugata has light gray to light grayish tan forewings, with many cross lines and bands of color in a pattern characteristic of many of the Larentiinae or so-called carpet moths (so called, I suspect, because the pattern of lines and bands is reminiscent of the border patterns of some oriental carpets). It can be distinguished from other similar species by its relatively wide dark reddish brown or black median area, and the double blackish spot in the subterminal area below the apical patch. The dark reddish brown median is characteristic of the type, which I seldom see; most of the specimens at my location are the form with the black median. The basal area is usually reddish brown, often with a fairly wide band of orange-brown bounded at the outer edge by a double whitish line preceding the black median area. The outer edge of the median is bounded by a moderately wavy double whitish or white and orange-brown line. The apical patch is usually brownish and somewhat diffuse. The double black spot in the subterminal area may also be somewhat diffuse, but is invariably present. A similar pattern of cross-lines is present on the pale hindwing, but much fainter and without the bands of color. Covell (1984) indicates a wingspan of 1.8 to 2.5 cm.

According to Handfield (1999) and Covell, the larvae of Xanthorhoe ferrugata feed on a variety of low plants, including chickweed, ground ivy, knotweed, smartweed and others. Handfield indicates two generations per year for my general area, with adult flight seasons from early May into the second half of June, and from about the beginning of July to early September.

My records to date for Xanthorhoe ferrugata (each date representing "the night of") are in the table below: