* larval remains = remains of a dead fly larva was inside the leaf mine and that section of mine was preserved for analysis, empty mine = no signs of larval remains inside the leaf mine, unknown = leaf mine not examined under a microscope and thus unknown if it was empty or contained larval remains.

** In some cases, multiple specimens (either multiple leaf mines or multiple larval remains) were pooled into a single sample to ensure sufficient DNA to make an identification.

*** At least 1 out of 3 replicate qPCR tests was positive for L. sativae.