Deparia acrostichoides
{{Short description|Species of fern}}
{{Speciesbox
| name = Silvery glade fern
| image = Deparia acrostichoides02.jpg
| status = G5
| status_system = TNC
| genus = Deparia
| species = acrostichoides
| authority = (Sw.) M. Kato
| synonyms =
{{Species list
|Asplenium acrostichoides |Sw.
|Asplenium thelypterioides| Michx.
|Athyrium acrostichoides| (Swartz) Diels
|Athyrium thelypterioides| (Michx.) Desv.
|Diplazium acrostichoides| (Swartz) Butters
|Diplazium thelypteroides| (Michx.) C. Presl
|Lunathyrium acrostichoides| (Sw.) Ching
}}
| range_map = DEAC4.png
| range_map_caption = Range within North America
}}
Deparia acrostichoides, commonly called silvery glade fern or silvery spleenwort, is a perennial species of fern. Its range includes much of the eastern United States and Canada, from Ontario to Nova Scotia and Georgia to Louisiana, as well as eastern Asia in China, Russia, Japan and Korea.{{cite web|title=Tropicos {{!}} Name - Deparia acrostichoides (Sw.) M. Kato|url=http://www.tropicos.org/Name/26608777?tab=synonyms|website=www.tropicos.org|access-date=23 June 2016}}{{cite web|title=Plants Profile for Deparia acrostichoides (silver false spleenwort)|url=http://plants.usda.gov/core/profile?symbol=DEAC4|website=plants.usda.gov|access-date=23 June 2016}} The name silvery comes from the fact that the indusia on the underside of the leaf have a silver color when the sori are close to ripening.
Description
Silvery spleenwort has pinnately divided yellowish green leaves arising from a stout, green, slightly brown hairy and scaly stem. The stem is typically grooved on the upper side, much shorter than the leaf blade and darker colored near its base, being dark red or brown; as the stem reaches the leaflets it becomes a pale green color. The leaves are broadest in the middle with a long pointed tip and tapering base, with the lowest pair of leaflets generally pointing downward. The tapering and downward pointed bottom leaves are a diagnostic characteristic for helping to distinguish this fern from similar ferns.
The leaves are {{convert|30|-|80|cm|in|abbr=on}} long and {{convert|10|-|25|cm|in|abbr=on}} wide; their underside is covered in fuzzy yellow-green hairs. There are approximately 18 leaflets on a leaf, which are approximately {{convert|15|cm|in|abbr=on}} long and {{convert|1|cm|in|abbr=on}} wide and relatively straight. The leaflets are themselves cut into oblong subleaflets which may have a blunt or rounded tip. The sterile and fertile leaflets are similar in form. The fertile leaves bear sori on the underside of the leaves and are silvery green at first but later become light brown as they ripen. The sori are pinnately arranged on the subleafets in a pattern which follows the veination; they are typically straight or slightly curved with a thick indusia with an entire margin.{{cite book|last1=Rhoads|first1=Ann|last2=Block|first2=Timothy|title=The Plants of Pennsylvania|date=5 September 2007|publisher=University of Pennsylvania press|location=Philadelphia Pa|isbn=978-0-8122-4003-0|edition=2}}{{cite book|last1=Foster|first1=Boughten Cobb ; illustrations by Laura Louise|title=A field guide to ferns : and their related families : Northeastern and Central North America : with a section on species also found in the British Isles and Western Europe|date=1987|publisher=Houghton Mifflin|location=Boston|isbn=0-395-19431-8|edition=[New ed., pbk. ed.].|url-access=registration|url=https://archive.org/details/fieldguidetofern0000cobb_o6z6}}{{cite web|title=Taxon Page|url=http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=233500569|website=www.efloras.org|access-date=23 June 2016}} The fertile pinnae can be described as acrostichoid as the sporangia covers almost the entirety of the underside of the leaf surface.{{cite book|last1=Coulter|first1=John|title=The Botanical Gazette (volume LXIV)|publisher=University of Chicago Press|date=1917|page=[https://archive.org/details/in.ernet.dli.2015.271626/page/n399 347]|url=https://archive.org/details/in.ernet.dli.2015.271626|access-date=26 June 2016}} Acrostichoid is also the term from which D. acrostichoides derives its species name.
It often forms extensive colonies, growing from creeping roots. Silvery spleenwort is a common fern in stream bottoms, moist woods, and cool shaded areas throughout its range.
Gallery
Deparia acrostichoides (12840222535).jpg |Showing ripened sori and indusia
Deparia acrostichoides 9.jpg|Showing unriped silvery indusia which gives this species its name
Gjk-deparia thelypterioides.gif|Leaf shape
Deparia acrostichoides.jpg|Stipe texture