Elaiosome
From Wikipedia, the free encyclopedia
Elaiosomes (elaios- oil, some- body) are fleshy structures that are attached to the seeds of many plant species. The elaiosome is rich in lipids and proteins, and may be variously shaped. Many plants have elaiosomes to attract ants, which take the seed to their nest and feed the elaiosome to their larvae. After the larvae have consumed the elaiosome, the ants take the seed to their waste disposal area, which is rich in nutrients from the ant frass and dead bodies, where the seeds germinate. This type of seed dispersal is termed myrmecochory from the Greek "ant" (myrmex) and "dispersal" (kore). This type of symbiotic relationship appears to be mutualistic, as the plant benefits because its seeds are dispersed to favorable germination sites, and also because it is planted (carried underground) by the ants. Elaiosomes are an example of convergent evolution, having evolved many times in thousands of different plant species. Elaioplasts is another name for fat-producing cells (plastids).
Some examples of plants that have elaiosomes are:
The particular elaiosome in plant family Euphorbiaceae is called caruncle (lat. caruncula: wart). Seed bearing a caruncle is carunculate, seed not bearing a caruncle is ecarunculate.
 Afzelia africana sead bearing elaiosomes |
 Carunculate seed of Ricinus communis (Castor beans) |
 Carunculate seed of Euphorbia mafingensis |
[edit] See also
Capitulum, a similar appendage with similar purposes found in stick insect eggs.
