Tabanidae of Canada, east of the Rocky Mountains 1: a ...

Key to the Stonemyia females of Canada east of the Rocky
Mountains
The two eastern species in this genus are similar and are usually
separated on the basis of differences in the colour of the legs and/or
colour of the abdomen (Teskey 1990, Pechuman 1981; Pechuman et
al. 1961). However, because of within-species variability and wear, it
may not always be possible to identify every specimen to species.
Pechuman (1981) found that all the Adirondack (New York) records of
S. rasa (Loew) were misidentified specimens of S. tranquilla (Osten
Sacken).
Stonemyia tranquilla flies from mid July–late August and has a more
northern distribution than S. rasa, which flies from late July-
September. Both are 11-13mm in length.
Key here.
Distribution maps S. rasa, S. tranquilla.
return to start of key to subfamilies and genera of Tabanidae