Korthalsella degeneri is a brittle, hemi-parasitic plant that utilizes haustoria to penetrate its host for nutrients. Its stems are relatively short, ranging from 10 to 20 cm long, and are extensively branched from a central stem that becomes less obvious beyond the first internode. The stems arise in a distichous pattern and are cylindrical at first, later becoming flattened. The stems are uniform in width and feature indistinct nerves. Its leaves are highly simplified and reduced, fusing into a ring around the opposite distichous stems without stipules. The flowers are unisexual and minute, situated in clusters within the leaf axils, often surrounded by dark hairs. These clusters contain both staminate and pistillate flowers that develop further into many-flowered groups through the emergence of adventitious buds, sometimes forming a continuous band around the stem. The calyx is absent in these flowers. Pistillate flowers exhibit a 3-lobed corolla with short, triangular lobes, while staminate flowers present as globose in the bud, later revealing three triangular segments. The stamens of the staminate flowers form a globular synandrium with six cells, discharging pollen through a central, apical pore. The ovary of the pistillate flowers is inferior, clavate, or pear-shaped, leading to a terminal style and a nipple-shaped stigma. The embryo sacs grow downward and then curve upward, taking a U-shape within the ovary wall. The fruit is a berry with a persistent, fleshy, and glossy corolla, each containing a single seed flattened at the upper portion and lacking a seed coat, with starchy endosperm and chlorophyll. It is typically found in diverse mesic forests at approximately 300 meters.