This morphotype may be the best fit for the name Harmandiola helena; see ID Notes on that page for more info.
Green to pink-red globular galls on Populus tremuloides showing equally on both sides of the leaf, often confluent where several grow nearby and sometimes sprawling onto adjacent veins, frequently found at the base of the leaf (but apparently never galling the petiole), succulent and thick-walled. They are unique among Populus leaf galls in having a circular rather than linear exit hole, which is typically but not always found on the upper side of the leaf. Circles are often visible before midges emerge, and these incipient holes are often seen on the opposite side of the one where midges eventually emerge as well. They are glossier and more succulent in texture than those of most Harmandiola galls. Variation in shape and density is greater for this morphotype than in many others, including some galls which present as a single large sphere rather than a flat cluster. Some of these variations may end up representing distinct species of midge inducers.
These galls resemble those Bladmineerders attributes to either Lasioptera populnea or Contarinia populi. It may not belong in the genus Harmandiola.
This gall morphotype can be distinguished from other midge galls on Populus leaves by the following traits:
- Gallformers Contributors: (2024) Gallformers ID Notes©