Ostrich fern (Matteuccia struthiopteris) growing in Vuosaari, Helsinki

Matteuccia struthiopteris (Vuosaari, Helsinki) | Source

order: Polypodiales
family

Onocleaceae

Sensitive ferns

1 genus:

Description

Ferns with fronds that bear sporangia having a different appearance to the fronds that do not. Stipes have two vascular bundles that unit towards the base of the blade and form a curved, flat-bottomed, gutter-like shape in cross-section. Sori are enclosed by reflexed leaf margins and membranous indusia. Spores are reniform.

Occurrence map Sensitive ferns (Onocleaceae) in Finland

Source

References:

  1. Smith, A. R., et al. (2006). A classification for extant ferns. Taxon, 55(3), 705-731. doi: 10.2307/25065646