Hexalobus monopetalus is a species of plant in the family Annonaceae with the common name baboon's breakfast. It is native to Angola, Benin, Botswana, Burkina Faso, Cameroon, Central African Republic, Chad, Gambia, Ghana, Guinea, Guinea-Bissau, Ivory Coast, Liberia, Malawi, Mali, Mozambique, Namibia, Niger, Nigeria, Senegal, South Africa, Sudan, Tanzania, Togo, Uganda, Zambia, Zaire and Zimbabwe. Achille Richard, the French botanist who first formally described the species, using the basionym Uvaria monopetala, named it after its petals which are fused at their base.
It is a bush or small tree reaching in height. It can have multiple stems, and either an upright or spreading posture, and its lowest branches may lie on the ground. Its bark is gray and variably textured from smooth, to rough, to flaky. Its petioles are 1âÂÂ4 by 1.2 millimeters with a channel on their upper side. The petioles are covered in curly, light-colored hairs that are 0.2-0.3 millimeters long. Its oblong to elliptical, papery to slightly leathery leaves are 3.6-17.5 by 1.2-6.5 centimeters with rounded to shallowly pointed tips (sometimes slightly notched), and rounded to wedge-shaped bases. The upper sides of the leaves are slightly glossy and hairless to sparsely covered in cream-colored hairs that are 0.3 millimeters long. The undersides of the leaves are hairless to densely covered with straight to curly hairs that are 0.2-0.8 millimeters long. The leaves have 6âÂÂ15 pairs of secondary veins emanating from their midribs at angles of 50ðâÂÂ80ð that arch and connect with one another near the leaf margins. Its fragrant flowers occur in groups of 1âÂÂ3 among leaves, on twigs, or directly from the trunk and are born on short, 2 by 2 millimeter peduncles. The peduncles have 5âÂÂ6, oval, concave bracts that are up to 5 by 3.5 millimeters. At maturity the peduncles are covered in dense cream to rust-colored hairs that are 0.3 millimeters long. Its oval to round flower buds are 3-5 millimeters in diameter. Its flowers have 3, broadly oval, concave sepals that are 4âÂÂ7 by 3.5.5 millimeters and fused at the base. The outer surfaces of the sepals are covered in silky hairs and the insides are wrinkled. Its flowers have 6 petals arranged in two rows of three. The light-yellow petals are fused at their bases to form a tube with narrow, lance-shaped lobes. The bases of the floral tubes are 2.5-4 millimeters long. The lobes are 9âÂÂ27 by 3.7 millimeters with irregular folds and shallowly pointed to rounded tips. The margins of the inner petals are curved back to form hollow chambers in the basal tube. The outer surface of the corolla is covered in 0.1 millimeter-long white, silky hairs that turn to rust-colored 0.2 millimeter-long, silky hairs at the base. The inner surface of the corolla is covered in short hairs, except the base which is hairless. Its flowers have numerous oblong stamen that are 1.4-2.1 by 0.5-0.8 millimeters. The connective tissue between the lobes of the anthers extends upward to form a disc-shaped cap. Its flowers have 2âÂÂ7 carpels that are 2.1-3 by 0.8-1 millimeters and covered in dense gold to rust-colored hairs. Its bilobed stigma are 1-1.3 millimeters long. Its brilliant red, elliptical to cylindrical fruit occur in groups of 1âÂÂ5 and are 2.2-4.6 by 1.3-2.2 centimeters. The contour of the fruits surface can be constricted around its seeds and is warty to wrinkled. The fruits are covered in short hairs. The fruit have light-colored pulp. The fruit have 2âÂÂ11 brown, flat, elliptical to oval seeds that are 10âÂÂ15 by 7-10 millimeters and are arranged in 1âÂÂ2 rows.
The pollen of H. monopetalus is shed as permanent tetrads.
It has been observed growing in savannas in forest corridors at elevations of 0 to . It prefers sandy soil or dry rocky substrates.
Bioactive molecules extracted from its fruit have been reported to have antifungal activity in test with Candida albicans.