Helanthium tenellum

Previouly known as Echinodorous tenellus.

Helanthium tenellum is a carpeting grass-like plant that bears a close resemblance to a mix between dwarf hair grass and micro swords. This plant grows by sending out lateral runners just like hair grass and other swords and when grown under proper conditions can spread to cover the foreground of your aquarium. For smaller nano tanks, this plant can also serve as a short background plant.

Image credits: pro shrimp