Ottawa (Dunrobin), ON Canada

5 June 2004   11:47PM EST

Zale unilineata, the One-Lined Zale, is one of a dozen species of Zale that have been recorded from the Ottawa area (J.D. Lafontaine, pers. comm., 2001).  My thanks to Dr. J. Donald Lafontaine of Agriculture Canada for confirming my identification of the specimen illustrated above, which was collected and given to the Canadian National Collection in Ottawa.

Zale unilineata has light to medium brown wings, somewhat paler in the area outside the postmedial line.  Most of the lines and markings are diffuse or obscure, the darker brown tracings present to varying degrees.  The exception is the postmedial line, present on the forewing as a sharp double line of yellowish white filled with a fine line of red-brown.  On the hindwing, the lower part of the pm line is finely edged with black.  In the specimen above, it is also possible to make out the inner edge of the reniform spot, as a darker, clearer partial outline with some hint of the ends curving outward around a slightly paler area with some dark shading.  There is also usually a somewhat darker patch of brown just inside the pm line at the costa on the forewing. 

According to Handfield (1999), the larvae of Zale unilineata may feed on black locust, but the host plant is not known with any certainty. Handfield indicates an adult flight season from early May to the end of June for my general area.

My only record to date for Zale unilineata (each date representing "the night of") is in the table below: