Badmin: Created page with "{{Taxobox | name = Discocactus | image = Discocactus_horstii.jpg | kingdom = Plantae | family = Cactaceae | subfamily = Cactoideae | tribe = Cereeae | subtribe = Cereinae | genus = '''Discocactus''' | notes = Taxonomy follows Joël Lodé (2015). Not to be confused with the epiphytic genus ''Disocactus''. }} == Etymology == The name is derived from the Greek ''diskos'' (disc) and refers to the characteristic flattened, disc-like shape of the plants, p..."

2026-04-02T16:43:06Z

Created page with "{{Taxobox | name = Discocactus | image = Discocactus_horstii.jpg | kingdom = Plantae | family = Cactaceae | subfamily = Cactoideae | tribe = Cereeae | subtribe = Cereinae | genus = '''Discocactus''' | notes = Taxonomy follows Joël Lodé (2015). Not to be confused with the epiphytic genus ''Disocactus''. }} == Etymology == The name is derived from the Greek ''diskos'' (disc) and refers to the characteristic flattened, disc-like shape of the plants, p..."

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{{Taxobox
| name = Discocactus
| image = Discocactus_horstii.jpg
| kingdom = [[Plantae]]
| family = [[Cactaceae]]
| subfamily = [[Cactoideae]]
| tribe = [[Cereeae]]
| subtribe = [[Cereinae]]
| genus = '''Discocactus'''
| notes = Taxonomy follows Joël Lodé (2015). Not to be confused with the epiphytic genus ''Disocactus''.
}}

== Etymology ==
The name is derived from the Greek ''diskos'' (disc) and refers to the characteristic flattened, disc-like shape of the plants, particularly as observed in the first species described in 1837.

== Description ==
'''Discocactus''' consists of low-growing, usually solitary, globose to strongly flattened cacti. They feature numerous ribs which are typically tuberculate and covered with robust, often flattened and curved spines.

A defining characteristic of a mature specimen is the **apical cephalium**—a dense, woolly structure at the stem apex from which stiff bristles often emerge.
* '''Flowers:''' Nocturnal, funnel-shaped, and pure white. They emerge rapidly from the cephalium and are intensely fragrant, adapted for pollination by hawk-moths (Sphingidae).
* '''Fruits:''' Globose, clavate, or elongated; slightly fleshy and fragile. They are typically white or pinkish and exhibit lateral dehiscence (splitting along the side).
* '''Seeds:''' Shiny, black, and covered with tiny papillae or tubercles.
* '''Dispersal:''' Primarily **myrmecochorous** (dispersed by ants), though hydrochory (dispersal by water) has been documented in species like ''D. bahiensis''.

== Habitat ==
The genus is native to the mountains and plateaus of northern Brazil, eastern Bolivia, and northern Paraguay. They grow at altitudes from 100 m (''D. ferricola'') up to 1300 m (''D. placentiformis''). They thrive in diverse, often extreme substrates:
* Rocky platforms and sandstone crevices.
* Ferruginous (iron-rich) red earths or manganesiferous black soils.
* Fine crystalline quartz sand (e.g., ''D. horstii'').
During severe droughts, many species exhibit **mimesis**, retracting into the soil and becoming covered with organic debris to survive desiccation.

== Distribution ==
* '''Bolivia:''' Santa Cruz.
* '''Brazil:''' Bahia, Ceará, Goiás, Maranhão, Mato Grosso, Mato Grosso do Sul, Minas Gerais, Pernambuco, Piauí, Tocantins.
* '''Paraguay:''' Amambay.

== Species and Subspecies ==
Joël Lodé recognizes 25 species and 14 subspecies:

* [[Discocactus bahiensis]]
** [[Discocactus bahiensis subsp. gracilis]]
** [[Discocactus bahiensis subsp. subviridigriseus]]
* [[Discocactus boliviensis]]
* [[Discocactus cangaensis]]
* [[Discocactus catingicola]]
** [[Discocactus catingicola subsp. griseus]]
** [[Discocactus catingicola subsp. rapirhizus]]
* [[Discocactus cephaliaciculosus]]
* [[Discocactus crassispinus]]
* [[Discocactus diersianus]]
* [[Discocactus estevesii]]
* [[Discocactus ferricola]]
* [[Discocactus hartmannii]]
** [[Discocactus hartmannii subsp. patulifolius]]
** [[Discocactus hartmannii subsp. setosiflorus]]
* [[Discocactus heptacanthus]]
** [[Discocactus heptacanthus subsp. magnimammus]]
** [[Discocactus heptacanthus subsp. melanochlorus]]
* [[Discocactus horstii]]
* [[Discocactus latispinus]]
** [[Discocactus latispinus subsp. pulvinicapitatus]]
* [[Discocactus lindanus]] (syn. ''D. lindaianus'')
* [[Discocactus pachythele]]
* [[Discocactus petr-halfari]]
* [[Discocactus piauiensis]]
* [[Discocactus placentiformis]]
** [[Discocactus placentiformis subsp. multicolorispinus]]
** [[Discocactus placentiformis subsp. pugionacanthus]]
* [[Discocactus prominentigibbus]]
* [[Discocactus pseudoinsignis]]
* [[Discocactus silicicola]]
* [[Discocactus silvaticus]]
* [[Discocactus squamibaccatus]]
* [[Discocactus subterraneo-proliferans]]
* [[Discocactus zehntneri]]
** [[Discocactus zehntneri subsp. albispinus]]
** [[Discocactus zehntneri subsp. boomianus]]
** [[Discocactus zehntneri subsp. buenekeri]]

== Taxonomy and Comments ==
* '''Phylogeny:''' Long believed to be related to ''Gymnocalycium'', recent molecular studies (Lendel et al., 2006; Ritz et al., 2007) show that ''Discocactus'' is actually closely related to ''Melocactus'' (formerly ''Meiocactus''). Both genera share the apical cephalium. Their flower differences (nocturnal/moths vs. diurnal/hummingbirds) are a result of specific pollinator adaptation.
* '''Classification:''' Moved from the tribe ''Trichocereeae'' to the tribe '''Cereeae''' (subtribe '''Cereinae''') based on the research of Nyffeler & Eggli (2010).
* '''Species Concepts:''' There is significant debate regarding the number of species. While some authors suggest only 7, and others up to 24, Lodé maintains a broader list to reflect the biodiversity observed in their vast and varied habitats. He notes that seedlings often show distinct differences between populations that adults tend to mask, suggesting that many synonymized taxa may indeed be distinct species or subspecies.

[[Category:Cactaceae]]
[[Category:Cactoideae]]
[[Category:Cereeae]]
[[Category:Cereinae]]

Discocactus - Revision history