Phytomyza spondylii

Larvae produce characteristic whitish serpentine leaf mines on Apiaceae hosts. Mines are visible as winding trails on the upper leaf surface. Adults are small black flies resembling houseflies in general form. Distinguished from the native North American holly leafminer Phytomyza ilicicola by host plant association: P. spondylii feeds on Apiaceae (hogweeds, masterworts, wild parsnip), while P. ilicicola is restricted to Ilex opaca (American holly).

Associated with host plants in the family Apiaceae, particularly in areas where Heracleum, Astrantia, or Pastinaca species occur.

France. Distribution records indicate presence in Norway (NO, PRESENT) per GBIF.

Larvae feed internally on leaf tissue of Apiaceae hosts. Documented host plants include Heracleum lanatum, Heracleum mantegazzianum, Heracleum sphondylium, Astrantia bieberstedtii, Astrantia carniolica, and Pastinaca sativa. Adults feed on plant sap obtained through punctures made with the ovipositor.

• Heracleum lanatum - host plantlarval development; contains furocoumarins
• Heracleum mantegazzianum - host plantgiant hogweed
• Heracleum sphondylium - host planthogweed
• Astrantia bieberstedtii - host plantmasterwort
• Astrantia carniolica - host plantred masterwort
• Pastinaca sativa - host plantwild parsnip

Larvae develop inside leaves, creating mines that expand as the larva grows. Pupation occurs within the leaf mine; the larva cuts a small exit window in the leaf epidermis before pupating to allow adult emergence. Adult emergence timing is presumably coordinated with host plant phenology, though specific details for this species are not documented.

Leaf miner; creates galleries within host plant leaves. Specialized biochemical detoxification of furocoumarins (8-methoxypsoralen) via enzymatic breakdown allows exploitation of Apiaceae hosts that are chemically defended against most herbivores.

• Phytomyza ilicicolaBoth are Phytomyza leafminers, but P. ilicicola is restricted to American holly (Ilex opaca) in North America and produces similar serpentine mines. Distinguished by host plant family and geographic range.

• leaf miner
• Apiaceae
• furocoumarin resistance
• serpentine mine
• herbivore adaptation

• BugGuide
• Wikipedia
• GBIF taxonomy match
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life
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