With over 100 species of Erica in the Klein River Mountains, you would be hard-pressed to call a winner amongst them in a beauty contest. But if one species were to take pride of place, then it would probably be Erica aristata. This is reflected in its common name Pride of Hermanus, although it occurs throughout the Klein River Mountains, so Stanford and Tesslaarsdal should share in some of that glory. However, it is unknown beyond the Klein River Mountains and is one of several Erica species endemic to this mountain range.
The name for Erica aristata is derived from its characteristic leaves rather than its beautiful flowers. Within the genus, even without flowers, the species is quite distinctive. The leaves are tough and curved downwards, with a stiff pointed, sometimes hair-like, end (“aristate”). The plants are not especially vigorous, often rather loosely branched with bare lower stems and only reaching a maximum of 70cm. However, each stem is topped by a cluster of about four broad and long-tubed flowers in shades of red, pink to almost white, with a deep maroon mouth.
Erica aristata belongs to section Euryloma, which contains many other stunning species, such as Erica ampullacea. They share in common a long tube, often narrowed towards the mouth, and four widely spreading lobes (from which the sectional name is derived: eury – wide, loma – border). The tube in Erica aristata is less constricted than some species of section Euryloma and the lobes are rather truncate. This helps to distinguish it from Erica retorta, which has similar curved and sharply pointed leaves, but a strongly constricted tube and pointed lobes.
The flower tube is extremely sticky on the outside. This prevents the nectar from being robbed by insects that might chew through the tube. Which then begs the question, what does pollinate such a beautiful flower? This was answered by Giorgio Lombardi during his time at Vogelgat Nature Reserve. Having spent 67 hours watching the flowers over a 3 year period, he recorded just 8 pollinator visits to the flowers. This demonstrates the rarity of pollinator visits to some of these fynbos plants. However, it was enough to confirm that it was only visited by long-proboscid flies of the Nemestridae family and just a single species at that: Prosoeca rubicunda. These amazing flies have a proboscis over 20mm long, about twice the length of their body. They use these sucking mouth parts to reach the nectar at the end of the tube (which is about 30mm long) and can hover in the air while doing so (thereby not getting caught by the sticky tubes). Part of the study also involved setting up a camera trap and they were lucky enough to capture one of these visits, which can be viewed here: https://www.sciencedirect.com/science/article/pii/S0254629921002660#ecom0002
A variety of Erica aristata, var. minor, was described (under Erica coruscana originally) with shorter tubes less than 20mm long. The species is remarkably variable in its colour and form along the Klein River Mountains for such a range-restricted species. On the face of it, there doesn’t appear to be any value in upholding this variety over any of the other variations that can be observed. However, considering the observations of the length of the proboscis in the pollinator for the normal variety, it is possible that a different species of Nemestridae pollinates this form and this would validate its recognition as a separate variety.
The species is usually found above 500m growing in short fynbos on ridges and amongst rocky outcrops. While restricted in its distribution, it is not particularly rare. However, invasions by pine trees and climate change could put the species at risk. At Phillipskop one needs to climb to the highest peak to find it, where it flowers between September and October.
