Petiole-gall
Guides
Andricus quercuspetiolicola
Oak Petiole Gall Wasp
Andricus quercuspetiolicola is a species of cynipid gall wasp that induces distinctive galls on white oaks (Quercus alba). The species name reflects its biology: 'quercus' for oak and 'petiolicola' indicating its habit of forming galls on leaf petioles and midribs. Adult wasps are small and inconspicuous, while the galls they produce are the most visible sign of their presence. Like other Andricus species, this wasp has a complex life cycle typically involving alternation between sexual and asexual generations on different oak tissues, though specific details for this species remain incompletely documented.
Dasineura tumidosae
Ash Petiole Gall Midge
Dasineura tumidosae is a gall midge in the family Cecidomyiidae that induces galls on ash trees (Fraxinus spp.). The species is known primarily from its association with ash petioles, where larvae develop within characteristic swellings. Like other Dasineura species, it has a narrow host range tied to specific plant tissues. The midge has been recorded from the northeastern United States, particularly Vermont.
Melikaiella flora
Live Oak Petiole Gall Wasp
Melikaiella flora is a cynipid gall wasp that induces distinctive leaf galls on live oak trees (Quercus agrifolia, Q. wislizeni, and Q. chrysolepis) in California. The species exhibits a complex life cycle involving two generations, with second-generation females ovipositing into acorns rather than leaf tissue. The galls typically engulf the entire petiole and may extend into the leaf blade, representing one of the more dramatic gall morphologies among North American Cynipidae. Formerly classified as Callirhytis milleri, the species was reclassified to reflect improved understanding of cynipid phylogeny.