1. Botrychium Sw. (grape fern)
Vegetative portion of the leaf pinnately compound (lobed elsewhere),
long-stalked or sessile, triangular in outline (linear to lanceolate
elsewhere), the veins branched, not anastomosing. Fertile portion of the leaf
erect, long-stalked, usually branched, the sporangia sessile to short-stalked,
densely clustered along the branches. Fifty to 60 species, nearly worldwide.
In addition to the species keyed below, B. campestre W.H. Wagner &
Farrar, the prairie moonwort, should be searched for in the loess hill prairies
of northwestern Missouri.
This species is widely scattered in Iowa and
has been found in several counties in the southwestern part of that state, near
border. The prairie moonwort is a member of subgenus Botrychium and can
be distinguished from other Missouri
species by the sterile leaf portions, which are oblong to linear, with 2–5
pairs of linear to spatulate, lobed pinnae. It is a diminutive plant mostly
less than 6 cm tall, and it is difficult to find in the dense prairie
vegetation where it grows.