IDM Cape Peninsula - Spiderheads - Serruria
Spiderheads are an exciting group to work with for many reasons:
Firstly the taxonomy is not yet updated. This means that concepts are changing and thus one must be prepared to accept name changes and sinking and emergence of species. However, outguessing taxonomists is fun.
Secondly, Spiderheads are largely a lowland group and thus have been heavily impacted by urbanization and agriculture. It is thus important that we find out more about them so that they can be properly conserved. Helping them allows us to save other species (both plant and animal) with similar habitat preferences.
But the speciality of the Spiderheads is that the Cape Flats just east of the Peninsula and the Peninsula itself are centres of evolution for the genus. Thus Serruria collina, Serruria decumbens, Cluster Spiderhead - Serruria glomerata, Serruria hirsuta and Golden Spiderhead - Serruria villosa are confined to the Peninsula. Serruria aemula, Spiderhead - Serruria cyanoides and Serruria trilopha have a portion of their decimated range (the portion still surviving in many cases) on the Peninsula. Serruria inconspicua occurs at one localized area on the Peninsula, forgotten behind (like Mimetes hirtus) when the Kogelberg and Cape Peninsula separated with the rising sea levels.
Thus Serruria at once presents a challenge and a treasure trove to those interested in plants. Understanding Spiderheads is understanding flowerhead structure and noting flower shape.
1. Note the flowerhead structure.
2. Note the shape of the flowers or styles.
Note also: One species creeps, two form sprawling mats, two occur as erect multiple-stemmed plants (which survive fires), and five are erect with a single stem at the base. So, remember to look at the habit of the plants - it will help you very much with your identifications.
The major sections of Spiderheads on the Peninsula are:
Flowerheads racemes. Styles straight like pins. Common Pin Spiderhead - Serruria fasciflora (erect), Serruria inconspicua (sprawling).
Flowerheads racemes. Styles kinked or incurved. Serruria collina (creeping), Serruria glomerata (erect).
Flowerheads racemes. Styles straight. Floral bracts large. Creeping. Leaf 3-pronged. Serruria decumbens.
Flowerhead a stalkless capitulum, clasped by leaves. Style straight.
Serruria hirsuta (hairy leaves, pink heads), Serruria villosa (yellow heads).
Flowerhead a capitulum with a prominent skirt of involucral bracts. Styles straight.
Serruria aemula foeniculacea (erect, single stem), Serruria cyanoides (short, fine, erect stems from an underground rootstock),
Serruria trilopha (sprawling, with robust multiple stems from an underground rootstock).