Phytomyza Atricornis/ Phytomyza Delphinivora/Phytomyza Columbinque: Appearance, Territory, Damage and Life Cycle

Common Names: chrysanthemum leafminer and cineraria leafminer

Appearance: In Britain, more than 800 insect species mine leaves as larvae, including beetles, sawflies, moths, and flies. The majority of the more than 300 species in the Agromyzidae family of true flies (Diptera) are leaf miners; many are quite specialized in host plants, while others can feed on a variety of species. Larvae of the Chrysanthemum leaf miner dig into the leaves of Chrysanthemum and other Asteraceae (daisy) plants.

Hosts Plants: Feeds nearly entirely on Asteraceae and has only been found on two hosts from other families, Daucus and Pisum.

Territory: North and South America, Europe and Africa Canary Island

Damage Insect Cause: The young maggot digs zig-zag pathways in the leaves. You can use neem seed kernel extract spray for the management.  The larvae feed inside the leaves, creating lengthy sinuous tunnels that appear as white or brown meandering lines on the top leaf surface. On host plants with small leaves, such as Argyranthemum and Pyrethrum, the whole interior of the leaf may be devoured, causing the entire leaf to discolor and dry out.

Life History and Habits: On the upper or lower leaf surface, the larva excavates a thin, linear mine. Pupation is present in the mine. There was little information provided about its ecology in Australia. The mature fly measures 2-3mm in length and is brownish black in color. Females scrape the leaf surface to feed on sap secreted by the plant, resulting in little pale patches on the top leaf surface. The larvae are creamy white legless maggots that can grow to be 3-4mm long. Pupae can be discovered in the leaves at the ends of mines during the pupal stage, which is pale brown. The fly larvae’s leaf mines disfigure the leaves, and huge populations can result in severe foliage loss. Plants in gardens and greenhouses might be impacted. The densest populations are usually found inside.