Eucalyptus megacarpa F.Muell.

Tree to 30 m, or mallee to 5 m. Bark white or yellow-white. Juvenile leaves alternate, petiolate, ovate, discolorous. Adult leaves alternate, falcate or lanceolate, acuminate; lamina 8.5–14 cm long, 2–3 cm wide, dull, green; lateral veins just visible, at 35°–45°; intramarginal vein up to 2 mm from margin; petiole flattened or angular, 15–25 mm long. Umbels 3-flowered; peduncle flattened, 10–26 mm long, to 7 mm wide; pedicels absent or up to 3 mm long. Buds ovoid to subglobular; operculum depressed hemispherical, apiculate, 10–12 mm long, 14–18 mm wide; hypanthium turbinate, 10–15 mm long, 14–18 mm wide. Fruits subglobular to campanulate, smooth or faintly striate, 16–25 mm long, 18–28 mm wide; disc broad, convex; valves 3–5, exserted but almost covered by disc. Seeds crescent-shaped, grey-black.

Grows in sandy loam in moist conditions near swamps and streams, in open forest. The mallee or smaller tree form is found on hills.