Parablechnum gregsonii
{{Short description|Species of fern}}
{{Speciesbox
| image = Blechnum fern.JPG
| image_caption = Growing below a waterfall near Lawson, New South Wales, Australia
| taxon = Parablechnum gregsonii
| authority = (Watts) Gasper & Salino
| synonyms =
{{Species list
|Blechnum gregsonii|(Watts) Tindale
|Blechnum capense var. gregsoni|Watts
}}
}}
Parablechnum gregsonii, synonym Blechnum gregsonii, is a type of fern, mostly seen in the Illawarra and Blue Mountains areas of eastern Australia, often near waterfalls and moist gullies.
Description
Parablechnum gregsonii is a fern with a creeping rhizome and pendent, mostly pinnate fronds {{convert|30-80|cm|in|sigfig=1|abbr=on}} long. The pinnae are bright green, mostly {{convert|7-15|cm|in|sigfig=1|abbr=on}} long with coarse teeth near the tips.{{cite web |last1=Wilson |first1=Peter G. |title=Blechnum gregsonii |url=http://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Blechnum~gregsonii |publisher=Royal Botanic Garden Sydney |accessdate=12 November 2018}}
Taxonomy and naming
This species was first formally described in 1915 by William Walter Watts from a specimen collected by "Mr Jesse Gregson...in 1902" and given the name Blechnum capense var. gregsonii. The description was published in the Journal and Proceedings of the Royal Society of New South Wales.{{cite web|title=Blechnum capense var. gregsonii|url= https://id.biodiversity.org.au/instance/apni/459230|publisher=APNI|accessdate=12 November 2018}}{{cite journal |last1=Watts |first1=William Walter |title=Notes on Blechnum capense |journal=Journal and Proceedings of the Royal Society of New South Wales |date=1915 |volume=49 |pages=125–126 |url=https://www.biodiversitylibrary.org/item/130155#page/157/mode/1up |accessdate=12 November 2018}} The specific epithet (gregsonii) honours Edward Jesse Gregson who collected the type specimen "on a wet ledge in the face of a perpendicular cliff overlooking a permanent creek in a gully at the base of Green Mountain, a little on the Bell side of Mount Wilson." In 1960, Mary Tindale elevated the variety to the species Blechnum gregsonii.{{cite web|title=Blechnum gregsonii|url= https://id.biodiversity.org.au/instance/apni/459543|publisher=APNI|accessdate=12 November 2018}} In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), this species is placed in the genus Parablechnum.