🐝 Ants, Bees & Wasps

Hazel Sawfly

Croesus septentrionalis

About Hazel Sawfly

A medium-sized sawfly with an orange abdomen and dark thorax. The bluish-green larvae with black heads feed gregariously on hazel, birch, and alder.

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Did You Know?

When disturbed, the gregarious larvae raise their tails simultaneously in an S-shape, creating an intimidating group display to deter predators.

How to Identify Hazel Sawfly

Hazel Sawfly (Croesus septentrionalis) belongs to the order Hymenoptera, family Tenthredinidae. Adults typically measure 8-10 mm.

Hazel Sawfly Habitat

Hazel Sawfly is found in heathland habitats, particularly across Europe, Western Asia. This species has adapted to thrive in its preferred environment, where it can find suitable food sources and shelter.

Hazel Sawfly Diet and Feeding

Hazel Sawfly is a herbivore, feeding on plant material including leaves, stems, flowers, and other vegetation. Herbivorous insects play a significant role in ecosystems by influencing plant growth and serving as a food source for predators.

Where Is Hazel Sawfly Found?

Hazel Sawfly can be found in Europe, Western Asia, where it inhabits heathland environments. Its distribution is influenced by climate, food availability, and habitat suitability.

Distribution Map

Where Hazel Sawfly can be found

Is Hazel Sawfly Dangerous?

Hazel Sawfly belongs to the order Hymenoptera, which includes many stinging insects. While not typically aggressive, it may sting if threatened or handled. Stings can cause pain and swelling, and in rare cases may trigger allergic reactions in sensitive individuals.

Hazel Sawfly Role in Nature

Hazel Sawfly is part of the food web as a primary consumer, feeding on plant material. It serves as an important food source for birds, bats, amphibians, and other insectivores, connecting plant energy to higher trophic levels.

Seasonal Activity

Jan
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Dec
Peak activity Moderate Low / dormant

Frequently Asked Questions About Hazel Sawfly

What does Hazel Sawfly look like?

The Hazel Sawfly typically measures 8-10 mm.

Where is Hazel Sawfly found?

The Hazel Sawfly is found in Europe, Western Asia and typically inhabits heathland environments.

What does Hazel Sawfly eat?

The Hazel Sawfly feeds on plant material including leaves, stems, and other vegetation.

Is Hazel Sawfly dangerous to humans?

The Hazel Sawfly belongs to the order Hymenoptera, which includes stinging insects. While not typically aggressive, it may sting if threatened or handled.

What is an interesting fact about Hazel Sawfly?

When disturbed, the gregarious larvae raise their tails simultaneously in an S-shape, creating an intimidating group display to deter predators.

Cite This Page

APA:
InsectDiscover. (2026). Hazel Sawfly (Croesus septentrionalis). Retrieved from https://insectdiscover.com/insect/hazel-sawfly

MLA:
"Hazel Sawfly." InsectDiscover, https://insectdiscover.com/insect/hazel-sawfly.