New Avocado Pest?

Jul 31, 2020

A new pest for avocado? Old pest? How much damage will it do? Don't know yet.

Tracy Ellis, the San Diego County Ag Commissioner Entomologist has partially identified what appeared to be two pest and a parasitoid, as only one pest and a beneficial that is doing it's duty going after the pest.

The insect determination has come back for both larvae (one a leaf miner and one a leaf roller) as the same insect! It has been determined to be C-rated gracillariid miner Caloptilia sp. (Lepidoptera: Gracillariidae) at this time. An image of the adult moth is not yet available.

Apparently, the larval stage transitions from a miner to a roller, in what's called hyper-metamorphosis. Starting as a miner and abandoning the mine to roll the leaf. CDFA scientist Marc Epstein is taking a closer look at this insect . Marc does not know if it is a local insect that adapted to avocados or is an import, as many in this family have not been studied or sequenced.

The leaf roller/folder has appeared down in San Diego and Santa Barbara. It's not clear whether it will be a pest of the fruit at this time.

The results for the parasite came back as Hymenoptera.  That too needs greater study.

 

caloptilia stages

Above is a photo of both insect stages. They can be found together in the same habitat.

 

caloptilia miner damage2

caloptilia miner damage1

The damage from the leaf miner generally looks like this

caloptilia miner

 And miner looks like this

caloptilia roller

caloptilia roller2

The damage from the leafroller looks like this:

 

caloptilia roller parasite

Larval leafroller with the parasite on it.

 

caloptilia parasite adult

And the parasite , once it grows up from being a maggot, looks like this

It's still not clear what damage this might do.  Maybe nothing significant.  Maybe this is an aberration only for this year.  Stay tuned.