- Leptosporangiate fern
Leptosporangiate ferns are vascular spore plants, whose
sporangia arose from a single epidermal cell and not from a group of cells as ineusporangiate fern s. The sporangia are typically covered with a scale (from Greek: 'lepis', 'lepidos') called theindusium , which can cover the wholesorus , but can also be strongly reduced. Many leptosporangiate ferns have anannulus around the sporanium, which ejects the spores.Most extant fern families are leptosporangiates. Examples are:
Dryopteridaceae ,Cyatheaceae ,Polypodiaceae ,Athyriaceae ,Woodsiaceae ,Onocleaceae ,Lomariopsidaceae andTectariaceae .References:
Smith, A. R., Pryer, K. M., Schuettpelz, E., Korall, P., Schneider, H., Wolf, P. 2006. A classification for extant ferns. "Taxon" 55(3): 705-731.
Sporne, K. R. 1962. The morphology of pteridophytes, the structure of ferns and allied plants. pp. 127-135. Hutchison & Co. London.
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