noun
vernal water-starwort (Callitriche palustris)
A small aquatic plant found in shallow water; the name is typically written in katakana.
湿地でミズハコベを見つけた。
I found vernal water-starwort in the marsh.
The name likely derives from 水 (mizu, 'water') and 繁縷 (hakobe, 'chickweed'), referring to its resemblance to chickweed and its aquatic habitat.