Cannabis, hemp

fam. Cannabaceae

1a pinnately branched corridor, main branch overlying the midrib: Liriomyza strigata

1b mine little branched, not associated with the midrib => 2

1c galls, etc => 100

2a final part of the mine strongly widened, blotch-like : Agromyza reptans**

2b a corridor from start to end => 3

3a pupation in the mine, in a, usually lower-surface, pupal chamber; first part of the corridor never spiralled: Chromatomyia horticola

3b pupation outside the mine; first part of the corridor in a dense spiral, unless the mine happens to start in a leaf tip: Liriomyza cannabis

100a Nematoda => 101

100b Acari => 102

100c Coleoptera => 103

100e Diptera => 104

100f Hemiptera => 105

100d Hymenoptera => 106

100g rust fungi => 107

100h smut fungi => 108

100i powdery and downy mildews => 109

100j other causers => 110

101 – Nematoda

101a Anguinidae: Ditylenchus dipsaci

101b Heteroderidae: Heterodera humuli

102 – Acari

102a Eriophyidae: Aculops cannabicolus

105 – Hemiptera

105a Aphididae: Phorodon cannabis

107 – rust fungi

107a Pucciniaceae: Aecidium cannabis; kriegeriana

109 – powdery and downy mildews

109a Erysiphaceae: Podosphaera macularis

109b Peronosporaceae: Pseudoperonospora cannabina

**This species is included in the key on the basis of relatively old information, in particular Hering (1957a). In Hering’s time it was not known that the name A. reptans included also A. pseudoreptans. See the key for Urtica< for the difference between the two species.