Aphids on the tip of purple foxglove, being attended by ants, which harvest the honeydew being secreted from the aphids. In the upper part of the image, a parasita wasp is visible (cf. upper image note). In the lower part, a few already parasitized dead aphids (brown and expanded) are visible (cf. lower image note).
In higher magnification, a parasitic wasp is well visible (cf. image note; the wings of wasp are oriented parallel to the wasp's body while the wings of winged aphids are standing upright.) The wasp injects an egg into the aphids and the larvae grow in the aphids, which finally causes some expansion of the aphids. Several aphids on the photo appear expanded and brown instead of black, indicating that they have already been parasitized.
Stem of a purple foxglove with living aphid colony and ants. Based on the wing orientation there seem to be several parasitic wasps on the colony (cf. image notes). These parasitic wasps can lay eggs in aphids undisturbed by the ants, because they have a chemical camouflage such that the ants think that the wasps are either other ants or are aphids.
Stem of a purple foxglove with dead aphid colony. The larvae grow inside the aphids, they eat from the inside out completely and then cut a round hole in the aphid, through which they finally leave the host. The ants are all gone because there is no more honeydew to collect.
Nominated as the most valued set of images on Wikimedia Commons within the scope: Aphids being attended by ants and parasitized by wasps. The corresponding categories are ants cultivating aphids and parasitoids.
Comment This type of work is unusual and high quality. I strongly agree. Maybe he should give thought to the formulation of the scope. I think we should link it to a category. --Archaeodontosaurus (talk) 16:56, 9 July 2012 (UTC)
Comment Thank you. There are two potential categories to link to (Ants cultivating aphids and Parasitoids), but none of the two fits perfectly, that is why a chose a scope apart from the categories. Is it possible to add both categories to the scope? -- Norbert Nagel (talk) 12:16, 10 July 2012 (UTC)
Comment I think anything otherwise. It's a good idea to put two category, in the scope. --Archaeodontosaurus (talk) 14:46, 10 July 2012 (UTC)