Callitriche

75 species are accepted. • Callitriche keniensis • Callitriche lechleri • Callitriche lenisulca • Callitriche longipedunculata – longstalk water starwort • Callitriche lusitanica • Callitriche mandonis • Callitriche marginata (synonym C. sepulta ) – winged water starwort • Callitriche mathezii • Callitriche mouterdei • Callitriche muelleri • Callitriche nubigena • Callitriche × nyrensis • Callitriche oblongicarpa • Callitriche obtusangula – blunt-fruited water starwort • Callitriche occidentalis • Callitriche oreophila • Callitriche palustris – spiny water starwort • Callitriche papuana • Callitriche pedunculosa (synonym C. nuttallii ) – Nuttall's water starwort • Callitriche peploides – matted water starwort • Callitriche petrieri • Callitriche platycarpa – various-leaved water starwort • Callitriche praetermissa • Callitriche pulchra – beautiful water starwort • Callitriche quindiensis • Callitriche raveniana • Callitriche regis-jubae • Callitriche rimosa • Callitriche schotsmaniana • Callitriche sonderi • Callitriche stagnalis – pond water starwort • Callitriche terrestris (synonym C. austinii ) – terrestrial water starwort • Callitriche transvolgensis • Callitriche trochlearis – effluent water starwort • Callitriche truncata – short-leaved water starwort • Callitriche turfosa • Callitriche umbonata • Callitriche × vigens • Callitriche vulcanicola • Callitriche wightiana ==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. ==References==