[Syrphidae] syrphidae and tree resin

[pseudotsuga at riseup.net]

Dear knowledeable folks,

I am intersted in studies and information pertaining to the relationship
between hoverflies (Syrphidae) and tree resin.

In particular, does any species of hoverfly spend it larval stage in tree
resin (resinous gobs on outside of tree)?  Have any of these species been
found doing this in North America?

I have only found one brief mention of this activity.  I am interested
because I research tree genetic engineering and am concerned about forest
ecology.

Thank you for wiritng me at pseudotsuga at riseup.net

Brian