Onocleaceae  

Onocleaceae is here segregated, following recent molecular phylogenetic research (Smith & al. 2006). It was formerly often included in Dryopteridaceae or Woodsiaceae. 

1. Sterile leaf blades pinnate with 30-70 pair of pinnae. Veins free. Stems obliquely ascending to erect, fronds arising in a group from a single rhizome (native) === Matteucia

1. Sterile leaf blades pinnate with 8-14 pair of pinnae. Veins reticulate. Stems creeping, fronds arising singly from different points along the long-creeping rhizome === Onoclea

Residence status of Matteucia struthiopteris (L.) Tod. in Belgium is controversial. According to Lawalrée (1962) it is a rare but locally native fern in damp woodlands on calcareous soils, confined to the Sambre-Meuse area (see however Duvigneaud 1974). Anyway, it is much more common and probably increasing elsewhere in Belgium as an escape from cultivation (Verloove 2002, Viane 2006; see also Bremer 2005).

Literature

Bremer P. (2005) Is er sprake van inburgering van Struisvaren (Matteucia struthiopteris (L.) Tod.) in Nederland? Gorteria 31: 122-125.

Duvigneaud J. (1974) La publication de l’Atlas Florae Europaeae. Nat. Mosana 27(3): 76-82.

Kato M. & Sahashi N. (1980) Affinities in the onocleoid ferns. Acta Phytotax. Geobot. 31: 127-138.

Lawalrée A. (1962) Matteucia struthiopteris (L.) Todaro (Athyriaceae) en Belgique. Bull. Jard. Bot. Etat Bruxelles 32: 309-323.

Lloyd R.M. (1971) Systematics of the onocleoid ferns. Univ. Calif. Publ. Bot. 61: 93 p.

Smith A.R., Pryer K.M., Schuettpelz E., Korall P., Schneider H. & Wolf P.G. (2006) A classification for extant ferns. Taxon 55(3): 705-731.

Verloove F. (2002) Ingeburgerde plantensoorten in Vlaanderen. Mededeling van het Instituut voor Natuurbehoud n° 20: 227 p.

Viane R. (2006) Matteucia struthiopteris. In: Van Landuyt W., Hoste I., Vanhecke L., Van den Bremt P., Vercruysse W. & De Beer D., Atlas van de flora van Vlaanderen en het Brussels gewest. Instituut voor Natuur- en Bosonderzoek, Nationale Plantentuin van België en Flo.Wer: 578-579.

Bremer P. (2005) Is er sprake van inburgering van Struisvaren (Matteucia struthiopteris (L.) Tod.) in Nederland? Gorteria 31: 122-125.