A plant organ (PO:0009008) in which plant spores (PO:0025017) are produced. [source: ISBN:0716710072, POC:curators]
Comment
In bryophytes, particularly in mosses, a sporangium is referred to as a capsule. In seed plants, a sporangium is located in a sporophyll. In pteridophytes, a sporangium is located on the surface of a sporophyll or fertile leaf or borne on a sporangiophore. May be unicellular in some algae.