leptosporangium

lepto- +‎ sporangium

leptosporangium (plural leptosporangia)

1. (botany) A sporangium formed from a single epidermal cell.
   • 2003, Jill Bailey, Filicinophyta (ferns), entry in The Facts on File Dictionary of Botany, page 84,

     In the Filicales the leptosporangium has a specialized spore dispersal mechanism involving an annulus of cells with thick walls that ejects spores explosively as it dries out.

   • 2010, Lily Bora, Principles of Paleobotany, page 256:

     The characteristic that unites the Filicales as a monophyletic clade is the presence of leptosporangia with an annulus-an area of specialized cells involved in dehiscence. […] Leptosporangia typically produce only a few spores, and are most commonly homosporous.

   • 2011, Michael G. Simpson, Plant Systematics, page 88:

     Leptosporangia are unique among vascular plants in (1) developing from a single cell, and (2) having a single layer of cells making up the sporangium wall.

• eusporangium

• leptosporangiate
• sporangium