Species Profenusa thomsoni - Amber-marked Birch Leaf Miner

Birch Leaf Miner

Profenusa thomsoni (Konow 1886)

4 mm(1)

native to, and widespread across the Palaearctic(2), adventive in NA and now transcontinental in the north(1)

Late May to Jul, may continue to emerge late into Aug(1)

hosts: primarily, Betulaceae, common on a number of birch species (Betula)(1)

Adults lay eggs in the leaf tissues. The larvae mine the leaves, forming light-colored blotch mines. Up to 40 larvae were found in a single mine. When all the leaf tissue is mined, regardless of the larvae age, they vacate the mine and drop to the ground. Only the latter part of the 5th instar enter the soil the survive.(3)

Introduced to NA early 1900s; spread westward, reached AB by 1970, reached Anchorage, AK ca. 1996

Species pages: anon. [AB](1) | Soper et al. (2009) | Ellis (2007) (Europe)(4) | Edmunds (2007) (UK)(5) | Pitkin et al. (2007-) (UK)(6)