Gratiola amphiantha is a rare species of flowering plant known by the common names little amphianthus, pool sprite and snorkelwort.

[3] It is limited to granite outcrops, a high-biodiversity habitat type that is threatened by activities such as quarrying, off-road vehicles, and trash and debris dumping.

Gratiola amphiantha is a petite aquatic plant which occurs in the non-Mediterranean climate vernal pools that sometimes form in the granite outcrop habitat.

[5] It is a delicate annual herb a few centimeter long with a short, threadlike stem surrounded by a rosette of tiny lance-shaped submerged leaves.

Above them are a pair of slightly larger, floating leaves which are oval in shape and up to 8 millimeters (0.3 inches) long.