File:Milkweed - or oleander - aphid, Aphis nerii.jpg

From Wikimedia Commons, the free media repository
Jump to navigation Jump to search

Original file(800 × 770 pixels, file size: 89 KB, MIME type: image/jpeg)

Captions

Captions

Add a one-line explanation of what this file represents
Description
English: Another member of the milkweed zoo, the milkweed [or oleander] aphid protects itself with cardiac glycosides, just like the monarch, and several beetles and true bugs. Botanists put milkweed and oleander in the same family now, based on DNA evidence.

The oleander aphid (Aphis nerii Boyer de Fonscolombe) is a distinct bright yellow aphid with black legs, antennae, cauda (tail-like appendage), and cornicles (tubes that extend from the abdomen). It is thought to originate in the Mediterranean and probably spread as oleanders were introduced around the world. The aphid is now found in tropical and temperate zones worldwide.

When the oleander aphid finds its preferred hosts, plants in the Asclepiadaceae and Apocynaceae, the population explodes. All of the aphids are females; they reproduce by parthenogenesis (clones of the mother) and they bear live young (nymphs). If conditions become too crowded on a plant or the plant declines in health, some of the aphids develop wings and will colonize new plants.

The aphids' bright coloring is a warning to predators. The aphids sequester the cardenolides (cardiac glycosides) produced by the milkweeds and dogbanes. When a predator disturbs the aphids, they exude the cardenolides in a waxy compound through the cornicles. Predators usually back away and clean the defensive compound from their mouthparts.

The amount of cardenolides present in milkweeds and dogbanes varies with the species, the age of the plant, and the season. Aphids that feed on plants with low amounts of the glycosides are more likely to fall prey to generalist predators like spiders, ladybug larvae, and aphid lions (lacewing larvae).

Generalist predators that survive eating the oleander aphids suffer the effects of the cardenolides. Fewer aphid lions survive to become lacewings and reproduce. Ladybugs develop deformed wings. And spiders weave strange disrupted webs.

The Bug Guide has posted a great photograph of oleander aphids taken by Lynette Schimming. To view these aphids on a milkweed, click on the link: bugguide.net/node/view/10569/bgpage
Date
Source Milkweed aphid, Aphis nerii
Author aroid from San Luis Obispo, CA, USA

Licensing[edit]

w:en:Creative Commons
attribution
This file is licensed under the Creative Commons Attribution 2.0 Generic license.
You are free:
  • to share – to copy, distribute and transmit the work
  • to remix – to adapt the work
Under the following conditions:
  • attribution – You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.
This image was originally posted to Flickr by aroid at https://www.flickr.com/photos/60546721@N00/260003978. It was reviewed on 16 July 2009 by FlickreviewR and was confirmed to be licensed under the terms of the cc-by-2.0.

16 July 2009

File history

Click on a date/time to view the file as it appeared at that time.

Date/TimeThumbnailDimensionsUserComment
current13:01, 16 July 2009Thumbnail for version as of 13:01, 16 July 2009800 × 770 (89 KB)Jacopo Werther (talk | contribs){{Information |Description= Another member of the milkweed zoo, the milkweed [or oleander] aphid protects itself with cardiac glycosides, just like the monarch, and several beetles and true bugs. Botanists put milkweed and oleander in the same family now,

The following page uses this file:

File usage on other wikis

The following other wikis use this file:

Metadata