Pseuduvaria calliura is a species of plant in the family Annonaceae. It is endemic to Borneo.[1] Herbert Kenneth Airy Shaw, the English botanist who first formally described the species, named it after the beautiful tails (Latinized forms of Greek Greek, Ancient (to 1453);: καλλι, calli-; and Greek, Ancient (to 1453);: ουρα, ura) or tips of its leaves.[2]
It is a tree reaching 10 meters in height. Its branches have sparse lenticels. Its mildly leathery leaves are 15.5-19 by 4.5-6.5 centimeters. The tips of the leaves come to a distinctive 35-50 millimeter long point. The leaves are hairless on their upper surface and densely hairy on their lower surface. The leaves have 12-16 pairs of secondary veins emanating from their midribs. Its densely hairy petioles are 4-8 millimeters long with a groove on their upper side. Inflorescences are organized on short, inconspicuous peduncles. Each inflorescence has 1 flower. Each flower is on a densely hairy pedicel 4-8 millimeters in length. The flowers unisexual. Its flowers have 3 sepals, 0.7-1 by 1-1.5 millimeters, that are partially fused at their base. The sepals are smooth on their upper surface, sparsely hairy on their lower surface, and have fine hairs on their margins. Its 6 petals are arranged in two rows of 3. The outer oval-shaped petals are 1.5 by 1.5-2 millimeters with smooth upper surfaces and sparsely hairy lower surfaces. The inner petals have a 2 millimeter long claw at their base and a 3.5-4 by 2.5-3 millimeter blade. The inner petals are sparsely hairy on their upper surface and densely hairy on their lower surface. Each inner petal has a horizontal, rod-shaped gland at the base of its outer surface. Male flowers have up to 24 stamens that are 0.6-0.7 millimeters long. Fruit are on sparsely hairy pedicels 7-12 millimeters in length. The fruit consists of up to 7 monocarps. Each mature monocarp is a 9-13 by 10 millimeter globe. The mature monocarps are green, wrinkly and hairy.[3] [4]
The pollen of P. calliura is shed as permanent tetrads.