Onocleaceae

Perlfarn ( Onoclea bilis )

The Onocleaceae are a family of genuine ferns ( Polypodiopsida ).

Features

The rhizomes are long to short creeping to ascending, sometimes forming processes ( Matteuccia, Onocleopsis ). The leaves are marked dimorphic: the fertile are otherwise substantially involved in shaping than the sterile. The petiole has two vascular bundles, which unite distal to a channel-shaped. The leaf blades are pinnate to pinnate. The nerve end free or anastomosing. The spores are kidney-shaped, brown to green. The sori are enclosed by the rolled- leaf margins. Sometimes additionally real indusia occur.

The basic chromosome number is x = 37 at Onoclea and 39 and 40 in the other genera.

Dissemination

The family is found mainly in the northern temperate regions and grows terrestrially.

System

The Onocleaceae family is monophyletic. My sister taxon are the Blechnaceae.

The family includes Onocleaceae to Smith et al. 2006, four genera with only about eight ways:

• Ostrich ferns ( Matteuccia death. ): The only three species occur in the temperate zones of the northern hemisphere.
• Perlfarne ( Onoclea L. ): The only four species in the temperate zones of the northern hemisphere.
• Onocleopsis F.Ballard: it contains only one type: Onocleopsis hintonii F.Ballard: It is distributed from Mexico to Central America.

Documents

• Alan R. Smith, Kathleen M. Pryer, Eric Schuettpelz, Petra coral, Harald Schneider, Paul G. Wolf: A classification for extant ferns. In: taxon. Volume 55, No. 3, 2006, ISSN 0040-0262, pp. 705-731, Abstract, PDF file.
• David John Mabberley: The Plant-Book. A portable dictionary of the higher plants. Cambridge University Press, Cambridge, among other things, 1987, ISBN 0-521-34060-8.