sgaorishal's picture

Holly Leaf Gall Fly

Observed: 25th May 2013 By: sgaorishalsgaorishal’s reputation in Invertebratessgaorishal’s reputation in Invertebratessgaorishal’s reputation in Invertebrates
holly leaf gall fly
Description:

A leaf affected by Holly Leaf Gall Fly Larva

Identifications
Species interactions

No interactions present.

Species with which Holly Leaf Gall Fly (Phytomyza ilicis) interacts

Comments

GrizzledBadger's picture

Mine or Gall

Agreeing with Latin binominal, but why is this termed a gall? Surely it is a leaf-miner, starting out as a serpentine mine & finishing as a blotch.

Brock

dejayM's picture

response

I guess it's a gall because of the reaction/response of the host tissue. But it is an interesting question as not all leaf miners have associated galls, nor do all host tissues react in the way shown here.
Gall - an abnormal colouration, swelling or excressence in the host tissue in response to 'attack' - my definition.
But Wiki does it well http://en.wikipedia.org/wiki/Gall
but, as you imply not all hosts respond in this way.
There is no reference about this being a gall in many of good sources e.g. http://www.nhm.ac.uk/nature-online/species-of-the-day/common-species/phy...
You will find however that if you search for Holly Leaf Gall Fly e.g. www.hbrg.org.uk/TRY/TRY_Pilicis.pdf some authoritative material emerges.