A multitude of wasps (body length = 1.22 mm) emerged from Casuarina equisitifolia branchlets collected from a tree in the beginning stages of decline at Polaris Point, Guam on 6 January 2009.  Microscopic examination indicates that the wasps are emerging from branchlet tips.

Infested trees have also been found in Yigo and Mangilao.  In some cases almost 100% of branchlet tips show feeding damage and exit holes.

Specimens were sent to John LaSalle in Australia.  John identifies the wasps as belonging to Eulophidae: Tetrastichinae:

“I returned from a week at the coast today to find the specimens of the small wasp on Causarina.
It is a bit troubling assigning it to genus – but I would say the closest fit would be Selitrichodes.
Selitrichodes is an interesting Australian genus which we just removed from synonym with Aprostocetus (I attach a pdf).
It is associated with galls – this is the first record of it being associated with anything but eucalypts.
We know of species in this genus which are gall inducers, as well as parasitoids of gall inducers.”

What appears to be the same insect was found by Aubrey Moore in Palau during March, 2009. Specimens were reared by the Palau National Invasive Species Coordinator, Joel Miles and these were sent to John LaSalle for comparison with those collected on Guam.