Callitriche antarctica

Callitriche antarctica is a small aquatic or semi-aquatic plant in the family Plantaginaceae. It features fleshy leaves with broadly connate bases forming a cup, and terrestrial leaves similar but smaller. The plant produces solitary flowers, with male flowers above and female flowers below. The fruit is subsessile, as wide as or wider than high, and lacks a wing. It is found across subantarctic and Antarctic regions, including islands such as Heard-McDonald, Kerguelen, and New Zealand South. It is distinguished from other Callitriche species by its fleshy leaves with connate bases. C. antarctica differs from C. aucklandica by the absence of a narrow wing on the fruit, though this can be difficult to discern in some specimens.