Mandl's picture

Insect

Observed: 26th May 2011 By: Mandl
Insect
Description:

Masses of these clinging to stems of Achillea like aphids. Size up to 3-4 mm. 3 pairs of legs, 2 antennae, green with black 'outlining', 2 vertical black 'spikes' at the rear of the body and a black 'tail' though on some of them this looks green and fat - depositing an egg?

Identifications
Species interactions

No interactions present.

Species with which Macrosiphoniella millefolii interacts

Comments

Dioctria's picture

Macrosiphoniella millefolii

Looks very like these aphids I photographed a couple of years ago: http://www.ispot.org.uk/node/23231

I contacted Richard Harrington, a UK aphid expert, after my iSpot post drew no response and he said they were "almost certainly" Macrosiphoniella millefolii.

Regarding the 'tail', when I was watching them through the macro lense they would regularly flick this (in unison as I recall) and I seem to remember reading that it is how some groups of aphids get rid of their waste fluids, by flicking them away.

David

Mandl's picture

Macrosiphoniella millefolii

Thank you, David, for the identification. Do you know anything about its life-cycle, effect on host plant and predators, if any?

Lynda

Dioctria's picture

Further Info

No, I'm afraid I've told you everything I know.

The plant in my own garden only had a couple of stems infested, and they didn't seem to be affected by the aphids' presence. I didn't do anything about them and they haven't reappeared since.

That said, it sounds like you have greater numbers so things may be different for your plants.

David

Dioctria's picture

Forgot to mention

They can apparently caused galls on the flower heads though I didn't see this on my plants.

David

Mandl's picture

Dioctria

Several of the infected flower heads failed to open and seemed to be dried out, so I am concluding that the insects have sucked the sap out.