Malacocarpus
| Malacocarpus | |
|---|---|
| File:Malacocarpus erinaceus.jpg | |
| Kingdom | Plantae |
| Family | Cactaceae |
| Subfamily | Cactoideae |
| Tribe | Notocacteae |
| SubTribe | |
| Genus | Malacocarpus |
| Species | |
| Notes | Taxonomy follows Joël Lodé (2015). Lodé treats Malacocarpus as a distinct genus from Notocactus and Wigginsia. |
Etymology
The name is derived from the Greek malakos (soft) and karpos (fruit), referring to the characteristic soft, fleshy, and often reddish fruits.
Description
Malacocarpus consists of solitary or occasionally clustering globose cacti, known for their woolly crowns.
- Stems: Typically flattened-globose to shortly cylindrical, reaching 10-20 cm in diameter. The apex is heavily covered with white or yellowish wool (a pseudocephalium).
- Ribs: Well-defined, usually straight, with prominent areoles.
- Spines: Variable, but often sturdy and slightly curved, ranging from few to many depending on the species.
- Flowers: Diurnal, appearing from the woolly apex. They are funnel-shaped and almost exclusively brilliant yellow with a reddish or purple stigma.
- Fruits: Very distinctive – soft, fleshy, berry-like, and typically pinkish or bright red. They stay embedded in the apical wool until ripe.
- Seeds: Small, helmet-shaped, black, and matt.
Habitat
The genus grows in temperate grasslands (Pampas) and rocky outcrops. They prefer well-drained soils and can withstand significant humidity and mild frost in their natural habitat.
Distribution
- South America: Southern Brazil, Uruguay, and Northeastern Argentina.
Species and Subspecies
Following Lodé (2015), the genus includes 8 recognized species and 2 subspecies:
- Malacocarpus arechavaletae
- Malacocarpus calvescens
- Malacocarpus corynodes
- Malacocarpus erinaceus (Type species)
- Malacocarpus langsdorfii
- Malacocarpus sellowii
- Malacocarpus sessiliflorus
- Malacocarpus vorwerkianus
Taxonomy
Often synonymized with Notocactus or Wigginsia, Joël Lodé maintains Malacocarpus based on the unique morphology of its soft, indehiscent fruits and the specific structure of the apical wool. Molecular data supports its position within the tribe Notocacteae, but as a distinct evolutionary lineage.
