Pilularia

Pilularia or pillworts is a genus of unusual ferns of family Marsileaceae distributed in North Temperate regions, Ethiopian mountains, and the southern hemisphere in Australia, New Zealand, and western South America.

Pilularia
Pillwort, Pilularia globulifera
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Division:	Polypodiophyta
Class:	Polypodiopsida
Order:	Salviniales
Family:	Marsileaceae
Genus:	Pilularia L.
Type species
Pilularia globulifera L.
Species
See text
Synonyms
Calamistrum von Linné ex Kuntze 1891

Depending on the taxonomic revisor, the genus contains between 3 and 6 species of small plants with thread-like leaves, and creeping rhizomes. The sporangia are borne in spherical sporocarps ("pills") which form in the axils of leaves. Pilularia minuta from SW Europe is one of the smallest of all ferns.

Phylogeny

Recent work from Pryer Lab^[1] accepted four species of Pilularia, with a fifth, P. novae-zealandiae, being conspecific with P. novae-hollandiae. In addition, another species, P. dracomontana, has been described from South Africa.^[2]

Phylogeny of Pilularia[3][4]	Other species include:
Pilularia P. minuta Durieu (least pillwort) P. novae-hollandiae A.Braun (Austral pillwort) P. americana A.Braun (American pillwort) P. globulifera L. (Common pillwort)	P. bokkeveldensis Crouch 2012 P. dracomontana N. R. Crouch & J. Wesley-Smith (Dragon-Mountain pillwort) P. ethiopica Eb.Fisch., Killmann, Mark.Ackermann & Yeshitela [5]