Sceptridium

Sceptridium is a genus of seedless vascular plants in the family Ophioglossaceae,^[1] closely allied to (and often included as a subgenus^[2] of) the genus Botrychium (the moonworts and grapeferns). It is also closely related to the genus Botrypus (the rattlesnake fern, often treated as the subgenus Osmundopteris under Botrychium). Sceptridium species are commonly called the grape-ferns.

Sceptridium
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Division:	Polypodiophyta
Class:	Polypodiopsida
Order:	Ophioglossales
Family:	Ophioglossaceae
Subfamily:	Botrychioideae
Genus:	Sceptridium Lyon
Type species
Sceptridium obliquum (Muhl. ex Willdenow) Lyon
Species
See text
Synonyms
Holubiella Skoda

These plants are small with fleshy roots, and reproduce by spores shed into the air. They differ from the moonworts in having at least some sterile fronds (all fronds in Botrychium are spore-bearing), and in the fronds being bi- or tri-pinnate (Botrychium are single pinnate, or rarely bipinnate); and from Botrypus in being evergreen, or at least winter-green (Botrypus are deciduous) and having the non-spore-bearing part of the frond long-stalked (short-stalked in Botrypus).

Phylogeny

Phylogeny of Sceptridium^[3][4]

(Hiemobotrychium) S. lunarioides (Michaux) Holub (winter grapefern)[5] (Sceptridium) S. schaffneri (Underwood) Lyon[6] S. decompositum (von Martius & Gal.) Lyon S. daucifolium (Wallich ex Hooker & Greville) Lyon S. atrovirens Sahashi S. formosanum (Tagawa) Holub S. multifidum (Gmelin) Nishida ex Tag. (leather grape-fern)[7][8][9][10][11][12][13] S. oneidense (Gilbert) Holub (blunt-leaved grape-fern)[7][14][15][16] S. biternatum (Sav.) Lyon (sparse-lobed grapefern, southern grapefern)[17] S. dissectum (Spreng.) Lyon (cut-leaved grape-fern)[7][18][19][20][21] S. microphyllum Sahashi S. × pseudoternatum (Sahashi) S. nipponicum (Makino) Holub S. robustum (Rupr.) Lyon S. triangularifolium Sahashi S. japonicum (Prantl) Lyon S. ternatum (Thunberg) Lyon

Unassigned species:

Botrychium rugulosum

• S. × argutum Sahashi
• S. australe (Brown) Lyon (parsley fern)^[22][23]
• S. biforme (Col.) Lyon (fine-leaved parsley fern)^[24][25]
• S. × elegans Sahashi
• S. javanicum Sahashi
• S. jenmanii (Underwood) Lyon (Alabama grape-fern)^[26][27][28]
• S. × longistipitatum Sahashi
• S. × pulchrum Sahashi
• S. rugulosum (Wagner) Skoda & Holub (ternate grape-fern, St. Lawrence grape fern, rugulose grape fern)^[7][29][30]
• S. × silvicola (Sahashi) Ebihara
• S. subbifoliatum (Brack.) Lyon (island grape-fern)^[31][32][33]
• S. underwoodianum (Maxon) Lyon^[34][35]