Callitriche antarctica Engelm. ex Hegelm.
Monoecious herb, palustral or ± terrestrial on wet ground. Stems thick, creeping below with ascending branches to 10 cm high. Lvs spathulate, thick, 2.5-10 × 1.5-4.8 mm, entire, 3-nerved, sometimes with free veins; base scarious and connate. Fls solitary, ♂ in upper axils, ♀ in lower, ebracteate or bracts falling early. Filaments to 1.3 cm long, tapering from broad base. Style 1.4-3.2 mm long, persistent. Fr. 0.8-1.1 × 1.1-1.5 mm, not keeled or winged; faces slightly convex; commissural groove open and shallow.
A., C., records from M. are doubtful.
Also indigenous to Subantarctic America, Kerguelen, and perhaps other subantarctic Is and Tasmania.
Terrestrial in damp places or palustral.
FL Oct-Feb.