teres (S.Watson) Bogin Sagittaria teres, the quill-leaved arrowhead[2] or slender arrowhead,[3] is an aquatic plant species in the genus Sagittaria.

It is a perennial herb up to 80 centimetres (31 inches) tall.

The flowers are white, up to 1.5 cm (1⁄2 in) in diameter, borne in one or more whorls on a stalk rising above the leaves.

[6] It grows along the shores of lakes, marshes, and other wetlands, frequently those with acidic water such as Sphagnum bogs.

[4][7][8] It is listed as endangered in Connecticut,[9] New Jersey, New York, and Rhode Island.