Polar Willow Gall Sawfly vs Arctic Sulphur
Side-by-side species comparison
| Attribute | Polar Willow Gall Sawfly | Arctic Sulphur |
|---|---|---|
| Scientific Name | Euura arcticum | Colias nastes |
| Order | Hymenoptera | Lepidoptera |
| Family | Tenthredinidae | Pieridae |
| Size | 3-5 mm | 36-46 mm wingspan |
| Habitat | Tundra & Arctic | Tundra & Arctic |
| Diet | Gall Makers | Nectar Feeders |
| Regions | Arctic Canada, Alaska, Greenland, Arctic Scandinavia, Svalbard | Arctic Canada, Alaska, Greenland, Rocky Mountain alpine zones |
| Conservation | Least Concern | Least Concern |
Polar Willow Gall Sawfly
A tiny sawfly that induces galls on Arctic willow stems by injecting chemicals during egg-laying. The larva develops safely inside the swollen plant tissue. Adults are small and dark with clear wings.
Did You Know?
The gall provides the larva with both food and insulation, maintaining temperatures several degrees warmer than the outside air.
Arctic Sulphur
A pale greenish-white butterfly with dusky wing margins and small dark discal spots. Its subdued coloration helps it absorb warmth while basking with wings spread. It rarely strays far from its alpine or arctic habitat.
Did You Know?
On overcast days, this butterfly can raise its body temperature 10 degrees above air temperature by basking laterally to maximize solar absorption.