Concertina plant (Crassula rupestris)

Description

What’s the World’s Favourite Species?

Concertina plant fact file

• Description
• Biology
• Range
• Habitat
• Status
• Threats
• Conservation
• Find out more
• Glossary
• References
• Print factsheet

Concertina plant description

The concertina plant is a spreading shrub that, during certain months of the year, becomes ablaze with colour due to the dense heads of pink flowers that form at the ends of the branches ⁽⁵⁾. The leaves of the concertina plant are lance-shaped to rounded, and are arranged opposite each other along the many branches ⁽⁶⁾. Most of the year the leaves are greyish in colour ⁽⁶⁾, but during the summer months the leaf margins turn a brilliant red or yellow ⁽⁷⁾.

Size

Height: up to 50 cm ⁽²⁾

Concertina plant biology

The concertina plant flowers from June until October ⁽²⁾. The pretty flowers attract bees, bumble bees, and sometimes even moths, which pollinate the plant. Tiny seeds develop following pollination, and their light weight allows them to be carried away from the parent plant by the wind. The dust-like seeds are blown into rock crevices or under bushes where, once sufficient moisture is available, germination will occur. Like many plants, while thousands of seeds may germinate, only a small percentage of this will survive to be mature, adult plants. Concertina plants may live for over 60 years ⁽⁷⁾.

Concertina plant range

Occurs in southern Namibia and in the Northern Cape, Western Cape and Eastern Cape provinces of South Africa ^{(2) (6)}. The subspecies C. r. commutata is restricted to a small area on both sides of the lower Orange River, while C. r. marnieriana has been recorded from the southern slopes of the Swartberg and Anysberg Mountains in the Western Cape province ⁽⁵⁾.

Concertina plant habitat

The concertina plant grows on dry, stony slopes ⁽²⁾. The subspecies C. r. marnieriana has very specific habitat requirements and grows only on Witteberg quartzite, usually on cliffs ⁽⁵⁾.

Concertina plant status

Subspecies Crassula rupestris commutata is classified as Vulnerable (VU) in Namibia on the Southern African Plant Red Data Lists ⁽³⁾. Subspecies C. r. commutata and Crassula rupestris marnierana are both classified as Least Concern (LC) globally, but Rare in South Africa, on the Interim Red Data List of South African Plant Taxa ⁽⁴⁾.

Concertina plant threats

The concertina plant species is not yet believed to be threatened. However, the subspecies C. r. commutata is threatened in Namibia by mining, which presumably degrades its habitat, and collection ⁽³⁾. Within South Africa, the subspecies C. r. commutata and C. r. marnierana are not yet threatened, but their limited distribution range in South Africa places them at risk of an unexpected event causing a critical decline, and thus they are classified as Rare on the Interim Red Data List of South African Plant Taxa ⁽⁴⁾.

Concertina plant conservation

The concertina plant occurs within the Cape Floral Kingdom, a ‘hot-spot’ of plant diversity in South Africa in which there are a number of protected areas ⁽⁸⁾. There are no known conservation measures in place for the threatened subspecies C. r. commutata within Namibia.

Find out more

For further information on the Cape Floral Kingdom and its conservation see:

• Wild Cape Nature Trust:
  www.wildcape.org

Authentication

Glossary

Cape Floral Kingdom

An area occupying about 90,000 square kilometres in South Africa that contains an incredibly high diversity of plant species (around 8,700 species), of which 68 percent are found no where else.

Germination

The beginning of growth, usually following a period of dormancy and in response to favourable conditions. For example, the sprouting of a seedling from a seed.

Pollinate

To transfer pollen grains from the anther (male part of a flower) to the stigma (female part of a flower) of a flowering plant. This usually leads to fertilisation, the development of seeds and, eventually, a new plant.

Subspecies

A population usually restricted to a geographical area that differs from other populations of the same species, but not to the extent of being classified as a separate species.

Witteberg quartzite

A type of hard, white-grey rock formed from sandstone rich in the mineral quartz.

References

1. Heywood, V.H. (1978) Flowering Plants of the World. Oxford University Press, Oxford.
2. Goldblatt, P. and Manning, J. (2000) Cape Plants: A Conspectus of the Cape Flora of South Africa. National Botanical Institute of South Africa, Pretoria .
3. Golding, J.S. (2002) Southern African Plant Red Data Lists. Southern African Botanical Diversity Network Report No. 14. SABONET, Pretoria.
4. Threatened Species Programme. (2007) Interim Red Data List of South African Plant Taxa. South African National Biodiversity Institute, Pretoria, South Africa. Available at:
   http://www.sanbi.org/biodiversity/reddata.htm
5. Court, D. (2000) Succulent Flora of Southern Africa. A.A. Balkema, Rotterdam, Netherlands.
6. Paterson-Jones, C. and Manning, J. (2007) Ecoguide Fynbos. Briza Publications, Pretoria, South Africa.
7. PlantZAfrica (February, 2008)
   http://www.plantzafrica.com/plantcd/crassularupest.htm
8. UNEP-WCMC: Cape Floral Protected Areas of South Africa (February, 2008)
   http://www.unep-wcmc.org/sites/wh/pdf/CAPE%20FLORAL%20REGION.pdf