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Blackberry Sawfly – Pamphilius dentatus

Blackberry Sawfly   Scientific Name:  Pamphilius dentatus Common Name:  Blackberry sawfly, web-spinning sawflies Appearance:  Blackberry sawfly is a unique insect related to the blackberry plant. They have a black, flattened abdomen, with females being larger than males. Their antenna is segmented along with transparent wings. The adult sawflies are 6 to 12 mm long, while the larva is short and pale with a hairy appearance. Host Plants or Food: As the name suggests, blackberry sawflies feed on blackberry leaves, making a tunnel out of them and then feeding in them. Territory: Throughout North America, Eastern USA, and Western USA Mode of Damage: The larvae are active leaf miners. They roll the leaves and tie them with silk webs to feed inside the webbed foliage. Their mode of feeding causes damage to the leaves, which affects the overall health of the plant. Habits and Life History: Blackberry sawflies are found among blackberry fields since they exclusively feed on their foliage. The female sawfly lays eggs on the underside of the leaves, beside the more prominent veins. As the eggs hatch, they give rise to larvae which roll down the leaves and form a silk web over them. The larvae then feed inside the web. Once the larva is fully grown, it drops to the ground, where it pupates throughout the winter season. The adults usually emerge during May.