American royal fern

American royal fern
American king fern ( Osmunda spectabilis )
Systematics
Department : Vascular plants (tracheophyta) Class : True ferns (Polypodiopsida) Order : Royal ferns (Osmundales) Family : King fern family (Osmundaceae) Genre : King ferns ( Osmunda ) Type : American royal fern
Scientific name
Osmunda spectabilis
Willd.

The American royal fern ( Osmunda spectabilis ) is a species of the royal ferns ( Osmunda ) within the family of the royal ferns (Osmundaceae). It was once considered identical to the king fern ( Osmunda regalis ), but molecular genetic studies in 2008 identify it as a distinct species. It is particularly common in eastern to central North America and there is evidence from Central to South America and the Caribbean islands. An English-language common name is royal fern.

description

Close up of a sterile frond

The American royal fern can be easily identified in the flora of the New World . Although it is similar to the (European) king fern, the (Japanese) Osmunda japonica and the (also Japanese) Osmunda lancea , only O. spectabilis occurs naturally in the New World. Its fronds can be up to a meter long and are double-pinnate (bipinnate). The leaflets are connected to the midrib by a very narrow base. The plant produces separate sterile and fertile fronds. They look similar at the base and in the middle part, but the terminal leaflets of the fertile fronds are greatly reduced and turn brown as they ripen in early summer.

distribution and habitat

The American royal fern occurs in eastern and central North America in the entire area from Newfoundland south to south Florida , from there west to east Texas and from there north to central Ontario . There are isolated finds from southern Mexico as well as from Nicaragua , Brazil , Argentina and the Caribbean .

It is most commonly found on wetter soils in wet meadows, moors, and along bodies of water.

Taxonomy

The American royal fern ( Osmunda spectabilis ) was previously regarded as a variety of the (European) royal fern ( Osmunda regalis : Osmunda regalis var. Spectabilis ). Another variety, Osmunda spectabilis var. Brasiliensis , (formerly Osmunda regalis var. Brasiliensis ) exists in the tropical regions of Central and South America, but is only recognized by a few authors.

Osmunda   subg. Claytosmunda  Osmunda claytoniana      subg. Plenary session  Osmunda javanica     Osmunda banksiifolia     Osmunda vachellii  subg. Osmunda  Osmunda regalis     Osmunda spectabilis     Osmunda japonica     Osmunda lancea

Osmunda angustifolia , Osmunda bromeliifolia and all extinct species of the genus Osmunda are not included in this cladogram . The classification is based on genetic analyzes by Metzgar et al. (2008).

Individual evidence

1. ↑ ^{a b} Jordan S. Metzgar, Judith E. Skog, Elizabeth A. rooms, Kathleen M. Pryer: The Paraphyly of Osmunda is Confirmed by Phylogenetic Analyzes of Seven plastid loci . In: Systematic Botany . 33, No. 1, September, pp. 31-36. doi : 10.1600 / 036364408783887528 .
2. ↑ ^{a b} Distribution Map - Taxon: Osmunda regalis var. Spectabilis . In: Flora of North America @ eFloras.org . Retrieved July 10, 2019.
3. ↑ ^{a b} Osmunda regalis spectabilis: observations . In: iNaturalist . Retrieved July 10, 2019.
4. ↑ ^{a b} Osmunda regalis var. Spectabilis (Willd.) A. Gray . In: Tropicos . Retrieved July 10, 2019.
5. ↑ Gary Fewless: Royal Fern . Cofrin Center for Biodiversity, University of Wisconsin, Green Bay. Retrieved September 11, 2011.
6. ↑ Royal Fern . Connecticut Botanical Society. Retrieved September 11, 2011.