Callitriche is a genus of largely aquatic plants known as water-starwort. Previously, it was the only genus in the family Callitrichaceae. However, according to the APG II system this family is now included in the Plantaginaceae (plantain family). The family name Callitrichaceae retains its status as nomen conservandum (name to be retained).
Callitriche longipedunculata, longstalk water starwort
Callitriche marginata, winged water starwort
Synonym Callitriche sepulta
Callitriche muelleri
Callitriche obtusangula, blunt-fruited water starwort
Callitriche palustris, spiny water starwort
Synonym Callitriche verna
Callitriche pedunculosa, Nuttall's water starwort
Synonym Callitriche nuttallii
Callitriche peploides, matted water starwort
Callitriche petrieri
Callitriche platycarpa, various-leaved water starwort
Callitriche sonderi
Synonym Callitriche capricorni
Callitriche stagnalis, pond water starwort
Callitriche terrestris, terrestrial water starwort
Synonym Callitriche austinii, Callitriche deflexa
Callitriche trochlearis, effluent water starwort
Callitriche truncata, short-leaved water starwort
Callitriche umbonata
Callitriche verna
Phylogeny and evolution
The first molecular phylogeny of the aquatic genus of 50 species discerned three clades: Clade A (three species, widespread); Clade C (10 species, New World); Clade D (six species, Europe). The parsimony analyses revealed that aneuploid reduction (n=5 to 4) and polyploidy (n=5 to 10) have evolved at least twice in the genus, whereas the obligately submersed growth habit and hypohydrophily have evolved once.
