Pseuduvaria grandifolia is a species of plant in the family Annonaceae. It is native to New Guinea. Otto Warburg, the German-Jewish botanists who first formally described the species using the basionym Stelechocarpus grandifolius, named it after its large (, in Latin) leaves (, in Latin).
It is a tree reaching in height. The young, dark brown to black branches are sparsely covered in hairs and also have sparse lenticels. Its large, egg-shaped to elliptical, papery to leathery leaves are 18.5âÂÂ32 by 6âÂÂ13.5 centimeters. The leaves have pointed to wedge-shaped bases and abruptly tapering tips, with the tapering portion 2âÂÂ10 millimeters long. The leaves are slightly hairy on their upper and lower surfaces except the midrib which is densely hairy on the underside. The leaves have 16âÂÂ24 pairs of secondary veins emanating from their midribs. Its sparsely to densely hairy petioles are 6âÂÂ12 by 2âÂÂ3.5 millimeters with a broad groove on their upper side. Its Inflorescences occur in groups of up to 10 on the trunk, and are organized on indistinct peduncles. Each inflorescence has up to 10 flowers. Each flower is on a densely hairy pedicel that is 15âÂÂ35 by 0.6âÂÂ0.9 millimeters. The pedicels are organized on a rachis up to 5 millimeters long that have 6âÂÂ10 bracts. The pedicels have a medial, densely hairy bract that is 1-1.5 millimeters long. Its flowers are male or hermaphroditic Its flowers have 3 oval sepals, that are 2âÂÂ3.5 by 3âÂÂ4 millimeters. The sepals are hairless on their upper surface, densely hairy on their lower surface, and hairy at their margins. Its 6 petals are arranged in two rows of 3. The white or maroon, oval to egg-shaped, outer petals are 3.5âÂÂ7 by 4.5âÂÂ6 millimeters with hairless upper surfaces and very densely hairy lower surfaces. The white or maroon, diamond-shaped, inner petals have a 1.7âÂÂ2.5 millimeter long claw at their base and a 6âÂÂ9 by 6âÂÂ7.5 millimeter blade. The inner petals have pointed bases and tips. The inner petals are slightly hairy on their upper surface and very densely hairy on their lower surfaces. The inner petals have numerous, irregularly shaped, raised glands on their upper surface. Male flowers have 48âÂÂ61 stamens that are 0.9âÂÂ1 by 0.6âÂÂ1 millimeters. Hermaphroditic flowers have 37âÂÂ45 stamens that are 0.9âÂÂ1 by 0.6âÂÂ1 millimeters. Hermaphroditic flowers have 11âÂÂ16 carpels that are 2-2.5 by 0.7âÂÂ1 millimeters. Each carpel has 6âÂÂ11 ovules arranged in two rows. The fruit occur in clusters of 3âÂÂ8 on densely hairy pedicles that are 18 by 2.5 millimeters. The orange, mature fruit are globe-shaped and 36âÂÂ38 by 29âÂÂ32 millimeters. The fruit are smooth, and densely hairy. Each fruit has 6âÂÂ11 hemispherical to lens-shaped seeds that are 10âÂÂ19 by 8âÂÂ11 by 2.5âÂÂ4.5 millimeters. The seeds are wrinkly.
The pollen of P. grandifolia is shed as permanent tetrads.
It has been observed growing in rainforests at elevations of .