Psychotria hathewayi var. hathewayi is a small tree reaching up to 8 meters in height. The young branches display yellowish to grayish-brown coloring. The leaves are simple and opposite. Blade shapes vary from obovate and oblanceolate to elliptic-oblong, occasionally suborbicular, measuring 2–12.6 cm long and 1.1–7.3 cm in width. Leaf apices are obtuse to rounded, with bases ranging from acute to truncate or rounded. Surfaces may be glabrous or show some pubescence, especially along the veins, and are generally chartaceous. Lateral veins appear in 5–11 pairs, with tertiary veins often forming a conspicuous network. Petioles range up to 1.2 cm long. Stipules are obovate or deltate–obovate, up to 6 mm long. The flowers are in inflorescences with verticillate branching, each branch typically ending in a three-flowered cymule. The flowers are unisexual, 4–5-merous, and usually heterostylous. The calyx is 3–3.5 mm long, hirsute, and 4-6-lobed. The corolla is white, 4-6-lobed, with a tube 2–3 mm long at anthesis and lobes 3–5 mm long that are often hirsute. Nectary disks are present at the ovary’s apex. The fruit is ellipsoid–pyriform, 12–18 mm long, with persistent calyx and sometimes an expanded disk. It contains 1-2(-4) pyrenes that are hemispherical in cross-section. The seeds are 1 per pyrene, usually conforming to the pyrene’s shape, with a thin seed coat and a well-developed oily endosperm. It is found in mesic to occasionally dry forests between 360 -940 meters.