Euphorbia caput-medusae ("Medusa's Head") is a plant of the Euphorbia genus, that occurs in and around Cape Town

Cape Town

Cape Town is the second-most populous city in South Africa, and the provincial capital and primate city of the Western Cape. As the seat of the National Parliament, it is also the legislative capital of the country. It forms part of the City of Cape Town metropolitan municipality...

, South Africa

South Africa

The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...

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This succulent really does resemble the head of Medusa, with many serpent-like stems arising from a short, central caudex.
It is still common around Cape Town

Cape Town

Cape Town is the second-most populous city in South Africa, and the provincial capital and primate city of the Western Cape. As the seat of the National Parliament, it is also the legislative capital of the country. It forms part of the City of Cape Town metropolitan municipality...

 where it grows in deep sand or rocky outcrops on the coast. It is particularly common in the Peninsula Shale Renosterveld

Peninsula Shale Renosterveld

Peninsula Shale Renosterveld is a unique vegetation type that is found only on the slopes of Signal Hill and Devil's Peak in Cape Town, South Africa. It is critically endangered and exists nowhere else...

 vegetation of Signal Hill

Signal Hill

-Places:in Canada * Signal Hill, Calgary, neighborhood and hill in Calgary, Alberta* Signal Hill-Quidi Vidi, provincial electoral district for the Newfoundland and Labrador House of Assembly, Canada...

. They sometimes exceed 1 metre in diameter, partly buried in the ground, covered with numerous crowded branches.