Pilularia americana A.Braun
-
Authority
Mickel, John T. & Smith, Alan R. 2004. The pteridophytes of Mexico. Mem. New York Bot. Gard. 88: 1-1054.
-
Family
Marsileaceae
-
Scientific Name
-
Description
Species Description - Plants forming dense clones; rhizomes ca. 1 mm diam.; leaves 1.5–10 cm, sparsely pubescent to glabrescent; sporocarp stalks 1– 3 mm long; sporocarps globose, 1.6–2.7 mm diam., covered with matted hairs until mature; raphes (attached portion of sporocarp stalk) very short, lacking teeth; sori 4 per sporocarp; 2n=20 (Arkansas).
-
Discussion
Type. U.S.A. Arkansas: Fort Smith, Nuttall s.n. (herbarium uncertain, but Nuttall collections known to be at BM, GH, LIV, and PH, among others; isotype NY!).
Most likely, this species is more common and widespread in Mexico than the relatively few collections suggest, at least in northwestern Mexico. Because of its inconspicuous and unfernlike appearance, probably it has been overlooked by collectors