Urediniospore

Urediniospores (or uredospores) are thin-walled spores produced by the uredium, a stage in the life-cycle of rusts.

Development
Urediniospores develop in the uredium, generally on a leaf's under surface.

Morphology

 * Urediniospores usually have two dikaryote nuclei within one cell. In mass they are usually pale brown in contrast to teliospores which are generally dark brown.