Aphid from space

[Dogghound]

Originally Posted by wyevilla

LordV

I wonder if the aphid seeks to distance itself from others of its species when it has been infected. This could be an adaptive behaviour to reduce the spread of the the parasite which would eexplain the isolated nature of your and my sightings.

Aphids do secrete alarm pheromones which cause other aphids to disperse usually by dropping off the plant. Species such as Aphidius eadyi cause the aphid to usually crawl to the upmost tip of the plant where it then dies. larva eventually cuts a small hole ventrally in the aphid's cuticle and attaches the aphid to the plant etc with its silk glands which is what has potentially happened in this photo as you can just about see the strands under the disk.

[Lord V]

Just an update on this- got this reply on Flickr.
"I emailed a guy who emailed a guy who said "I believe its the mummy of Discritulus planiceps from the European aphid Drepanosiphon platanoides, but I'm not totally sure. There are not many aphid parasitoids that pupate outside of the host, and apart from Praon I think Discritulus also does so, although in a rather more skillfull way."

Brian V.

[ste_]

Originally Posted by Venger

For a moment I thought you'd stuck it to a penny.

I did initially wonder how you got it pose on your penny and then, if it was a penny, it must be a huge aphid!

Fascinating stuff, not something I've seen before. Thanks for sharing.

Cheors,

[JRsbugs]

Originally Posted by Lord V

Just an update on this- got this reply on Flickr.
"I emailed a guy who emailed a guy who said "I believe its the mummy of Discritulus planiceps from the European aphid Drepanosiphon platanoides, but I'm not totally sure. There are not many aphid parasitoids that pupate outside of the host, and apart from Praon I think Discritulus also does so, although in a rather more skillfull way."

Brian V.

Thanks to a link given by Tiggrx to this thread I think you are correct with Drepanosiphon platanoides Brian. I have the same aphid, and found one mummified like yours, Jason has what looks to be the same.

Aphid Parasitisation!

The aphid is desscribed here..

Rothamsted Insect Survey

I have pics so will upload some. Mine was on the back of an Ivy leaf but there is a young Sycamore tree next to it, I have a larger tree on the edge of my drive not far away but a neighbour took it upon himself (without my permission) to cut it back and now I have too many young shoots! The tree was very tall and always dripped a lot of sticky stuff so I imagine it was from these aphids, good food for birds and I will be selecting a few branches to let them grow back.

Janet

[JRsbugs]

I searched for the wasp but couldn't find it, I had found a list of Braconidae and found it by searching just 'planiceps'.

Dyscritulus planiceps is the correct spelling.

[ollyk]

Originally Posted by wyevilla

LordV
I wonder if the aphid seeks to distance itself from others of its species when it has been infected. This could be an adaptive behaviour to reduce the spread of the the parasite which would eexplain the isolated nature of your and my sightings.

I was thinking that the aphid seeks solitude to preserve the parasite - Ants who milk aphids may(?) destroy sick examples and of course ladybirds and other aphid eaters will always tend to go where the numbers are high, and may pick off a slower aphid...

Just an idea!