Ottawa (Dunrobin), ON Canada

12 July 2003   9:28PM EST  (top left)
7 July 2003   11:27PM EST  (top right)
7 July 2003   9:57PM EST  (bottom left)
5 July 2003   10:51PM EST  (bottom right)

My initial identification of this species was based on Covell (1984) and subsequently checked against specimens in the Canadian National Collection in Ottawa, thanks to the kindness of Dr. J. Donald Lafontaine in arranging access to this resource.  This year, I have also checked specimens and photographs against the description in Hodges, R.W., The Moths of North America North of Mexico, Fascicle 7.1, Gelechioidea Gelechiidae (Part) Dichomeridinae (Washington: Wedge Entomological Research Foundation, 1986).

Dichomeris flavocostella is one of a number of Dichomeris species known to occur in the Ottawa area, several of which are quite similar in appearance.  The forewing is black, described as purplish black by Covell, with a yellowish white area along the costa extending about 3/4 of its length and reduced to a narrow grayish area closer to the apex.  The lower edge of the white area curves smoothly from the base to form a slightly outward-pointing tooth at about 2/3 of the way along the wing.  Viewed from above in the resting position, the white areas appear to outline a black tear-drop shape that is not quite closed at the bottom.  Hodges notes a wing length ranging from 6.5 to 8.1 mm, while Covell indicates a wingspan between 15 and 18 mm.

Both Hodges and Covell indicate that the larvae of D. flavocostella are leaf tiers on goldenrod.  In addition, Hodges mentions aster, while Covell mentions sunflower.

I have photographed this species in 2001, on 1, 8 and 10 July; in 2002, on 5 July; in 2003, on 5, 7, 10, 12, 14, 15, 18, 20, 21 and 22 July.