Callitriche

Callitriche, commonly known as water-starwort, is a genus of small, aquatic and semi-aquatic flowering plants in the family Plantaginaceae. The genus comprises about 30 species found worldwide, typically in freshwater habitats such as ponds, lakes, slow-moving streams, and wet soil. These plants are characterized by their submerged and emergent growth forms. Submerged leaves are typically linear and finely divided, while emergent leaves are often broader and spatulate, forming a rosette on the water's surface. The flowers are inconspicuous, lacking petals and sepals, and are borne in the leaf axils. Reproduction can occur both sexually and asexually. Callitriche species are often found in disturbed habitats and can play a role in nutrient cycling in aquatic ecosystems. Identification of species can be challenging due to their morphological plasticity and variation depending on environmental conditions.