It is a shrub or small tree reaching 5 meters in height. The branches are hairless and dark-colored. Its elliptical to narrowly oblong, sickle-shaped, papery leaves are 7.5-14 by 2-6 centimeters. The leaves have rounded to wedge-shaped bases and tapering tips. The leaves are hairless, or become hairless at maturity, and dark green. The leaves have 10-12 pairs of secondary veins emanating from their midribs. The secondary veins arch and connect near the margins of the leaves. Its petioles are 2-3 millimeters long, and hairless, with a groove on their upper side. Its solitary Inflorescences occur on branches and the trunk. Each inflorescence has 1 flower. Each flower is on a pedicel. The pedicels have a pair of basal bracts that are covered in silky-brown hair. Its flowers are unisexual. The male flowers are on 4-5 millimeter long pedicels that are positioned at leaf axils on branches. Male flowers have two rounded sepals that are 2 millimeters wide with silky hairs. Male flowers have 4 petals in a single whorl. The petals are narrowly elliptical, 6 by 3 millimeters and covered in brownish silky hairs. Male flowers have numerous, small, rectangular stamens that are 0.5 millimeters long and consist of an anther without a stalk (filament). The female flowers are on 6-10 millimeter long pedicels that are positioned on the trunk and at leaf axils on branches. Female flowers have two rounded to slightly pointed sepals that are 2 millimeters wide with sparse, brown, soft hairs on their outer surface. Female flowers have 4 petals in a single whorl. The petals are opal to pointed, and 5 by 7 millimeters. The petals are covered in pale grey hairs on their outer surface and are hairless on their inner surface. Female flowers have numerous carpels that are 3-3.5 millimeters long. The carpels have short, 0.5 by 0.6 millimeter, black stigmas that have dense, silky hairs. The fruit occur in clusters of 4–6 on pedicles that are 10-15 millimeters long. The fruit are cylindrical, constricted between the seeds, and 3.8-4.5 by 1.2-1.5 centimeters. Each fruit has 4-6 seeds in two rows. The seeds are 10–13 by 6-7 millimeters.[4]
The pollen of U. congensis is shed as permanent tetrads.[5]
It has been observed growing gallery forests.[4]
