Aspidiaceae (Fern Family)

Small to medium size ferns.
Fronds pinnate to bipinnate.
Fronds sprouting in clusters from stout rhizome (underground stem) or singly along fine rhizome.
Sori (sporangia clusters) round or roundish; can be elongated but having rounded, not pointed, ends.
Indusia (sori covering) present

Natural History:

Family Size:

World:

Genera:

Species:

North America:

Genera: 10

Species: 16

Yukon:

Genera: 7

Species: 11

Genera

Cystopteris (Bladder ferns)

Delicate medium sized ferns. Fronds pinnate or ternate. Indusium hood-shaped, attached one side and arching over rounded sori.

Dryopteris (Wood Ferns)

Usually large ferns with pinnate to bipinnate fronds arising in clusters. Indusium roundish reniform (kidney shaped), attached in center, covering sori.

Gymnocarpium (Oak Ferns)

Small ferns with ternate fronds. Arising singly along slender rhizome. Sori round, indusium absent.

Woodsia

Small tufted ferns. Can be identified by thread- or plate-like indusium, and round sori. Indusium attached below sori and more or less arched over them.

Illustrated Key To Aspidiaceae Species

Dichotomous Key To Aspidiaceae Species

A: Indusia absent: (Gymnocarpium)

B: 2 lower branches nearly as long as terminal one. Fronds essentially glabrous (smooth): G.dryopteris
B: 2 lower branches about half as long as terminal one. Fronds very glandular (with glands): G.jessoense

A: Indusia present

C: Indusia thread-like, attached below round sori (sporangia bundles), and arching over them: (Woodsia)

D: Frond stems and branches green: W.glabella
D: Frond stems and branches brown: W.alpina

C: Indusia covering sori attached at center or on one side:

E: Indusium roundish, attached at center:

F: Indusium reniform (kidney-shaped):D.fragrans
F: Indusium peltate (shield-shaped):P.lonchitis

E: Indusium hood-like, arching over sori, attached on one side: (Cystopteris)

G: Fronds bipinnate to tripinnate: C.fragilis
G: Fronds ternate: C.montana

Life Cycle

Mature sporophyte (Fern plant) produces spores in sporangia (spore producing organs) usually located in sori (sporangia bundles) found on the underside of leaves. (top middle and right)
Spores are dropped from the sporangia to the ground. (middle right)
Spores germinate into a heart shaped gametophyte (gamete producing plant) thallus (plant body not differentiated into stems and leaves). (bottom right)
Mature gametophytes produce microspores (male gametes, sperm) and megaspores (female gametes, egg). (bottom middle)
When wet, such as after rain, the microspores (sperm) swim out of the microsporangium and into the megasporangium, where one will fertilize the megaspore (egg). (middle left)
The sporophyte then grows out of the megasporangium and the gametophyte thallus dies. (top left)
The cycle begins again...

Aspidiaceae syn. Dryopteridaceae : Fern Family

Taxonomy | Illustrated Key | Dichotomous Key | Genera | Family Traits

Taxonomy

Scientific Name:

English Name(s):

Gwich'in Name:

Family Traits

Description: