Single-leaved Star

The first autumn rains bring the arrival of the Single-leaved Cape Stars, Pauridia monophylla, to the upper slopes of Phillipskop. These are members of the Hypoxidaceae family, one of the geophytic members of the fynbos flora with small corms. Most species flower in winter and spring, but the yellow star-shaped flowers of Pauridia monophylla appear before the leaves have fully developed. This is similar to another member of the family at Phillipskop, Empodium plicatum, but the two species are easily distinguished. As the scientific name describes, Pauridia monophylla has a single (mono-) leaf (phylla), which is channelled. Empodium plicatum on the other hand has 3 leaves that are pleated, as well as differences in the ovary.

Pauridia monophylla (Hypoxidaceae)
Pauridia monophylla with all petals spreading
Pauridia monophylla (Hypoxidaceae)
Old and new flower of Pauridia monophylla. Note how the fresh flower has the inner petals spreading upwards at 45°

Pauridia monophylla is actually quite unique within the genus Pauridia itself. While the autumn flowering (March to May) and the single leaf makes easy identification, the structure of the petals and stamens is also unusual for the genus. Most Pauridia have 6 similar spreading petals, but in Pauridia monophylla, the two whorls of 3 behave differently. The inner whorl is slightly narrower than the outer and not as spreading, sometimes even at 45° or more to the horizontal. Added to this the mouth of the tube is very narrow and the stamens sit tightly in the middle. Furthermore, the anthers open inwards towards the style (the only species in the genus to do this), suggesting that self-pollination is a common occurrence in this species.

Pauridia monophylla is a local endemic of the south-western Cape fynbos. It is mainly found from the Kogelberg through to Bredasdorp. The favoured habitat is the upper southern slopes of the mountains, where the ground is slightly damp in autumn, but lowland areas are also known. It is most noticeable after a fire but at Phillipskop it is reliable to flower besides the paths on the way up to the saddle. The flowers, which almost lack any stem, appear like they are lying scattered on the ground. They are usually closed in the morning but open fully by the afternoon as the day warms up.

Pauridia monophylla (Hypoxidaceae) with corm
Whole plant of Pauridia monophylla with solitar leaf, bract around the flower base and a corm

Despite its limited distribution it is not classified as at risk as it generally grows in upper mountain areas, which are not at risk of development. While these areas are vulnerable to invasion by non-native plants such as pine and hakea, at present the populations of Pauridia monophylla are large and widespread enough to not consider this a major threat.

Pauridia monophylla (Hypoxidaceae)
The flowers of Pauridia monophylla often appear directly at ground level. Note the inner petals are narrower than the outer ones as well as pointed slightly upwards. The small congested anthers can just be seen in the middle of the flower.

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