Penaea

Penaea is a genus of flowering shrubs and shrublets in the Penaeaceae family. The upper branches have four longitudinal ridges. The simple, opposite and overlapping leaves grow in four ranks, the blades leathery.

The flowers grow from axils of leafy stem-tip bracts. There are usually two bracteoles below a flower. The perianth tubes are cylindrical or cup-shaped, sometimes contracted at base and throat. This tube is up to 7 mm long. The erect lobes at the tip of the tube are shorter than the tube. The flowers are mostly yellow, sometimes pink or purple.

The four stamens arise in the throat of the perianth tube. They have filaments shorter than the anthers that reach more or less as high as the perianth lobe tips. The anthers are thickly fleshy and bear pollen sacs near the base. The superior ovary has four locules that have two to four ovules each. There is an unusual embryo sac developing after two rounds of mitosis, the process of cell division by which a single cell divides to produce two genetically identical cells. The style has four longitudinal membranous wings.

The fruit is a capsule with four valves, the style base persistent upon it. Only one brown, oblong seed with a funicle attached is usually produced per locule.

There are only four Penaea species, mostly found in the Western Cape but also in the west of the Eastern Cape; all occurring in the fynbos.

The plant in picture is Penaea mucronata (Leistner, (Ed.), 2000; Manning, 2007; https://www.britannica.com; https://pza.sanbi.org).