Phalacroseris is a perennial herb with fleshy herbage growing from a woody caudex.

The leaves are located around the base of the plant, growing up to 20 centimeters long and linear to somewhat lance-shaped.

The inflorescence reaches up to 35 centimeters tall and is topped with a head filled with many golden ray florets.

The fruit is a hairless, speckled, four-angled achene about 3 millimeters long.

It is endemic to the Sierra Nevada of California, where it grows in wet habitat such as moist meadows, bogs, and clearings in subalpine coniferous forest.