Trichocereus

From M&J Cactus Wiki
Trichocereus
File:Trichocereus pachanoi.jpg
Kingdom Plantae
Family Cactaceae
Subfamily Cactoideae
Tribe Cereeae
SubTribe Trichocereinae
Genus Trichocereus
Species
Notes Taxonomy follows Joël Lodé (2015) with molecular insights from Ritz et al. (2007), Arakaki (2008), Albesiano & Terrazas (2012), and Schlumpberger & Renner (2012).

Etymology

The name means "hairy Cereus", referring to the characteristic hairy floral tube.

Description

Trichocereus is a genus of columnar cacti ranging from creeping to massive tree-like forms.

  • Habit: Shrubby to arborescent; erect, decumbent or rarely pendulous; up to ~15 m tall.
  • Stems: Columnar, with straight ribs.
  • Areoles: Close-set, woolly.
  • Spines: Radial and central, highly variable; from fine acicular to strong subulate.
  • Flowers: Large, funnel-shaped; nocturnal or diurnal; white, yellow, red, pink or purple.
  • Floral tube: Long, thick, scaly, with dense hairs (usually dark).
  • Pollination: Extremely diverse — bees, moths, bats, birds and insects.
  • Fruits: Globose, thick-walled; hairy but spineless; pulp white.
  • Seeds: Small, dark brown to black, pitted; dispersal by ants, birds and bats.

Habitat

Extremely wide ecological range:

  • deserts, valleys, slopes, canyons and plains
  • rocky, sandy and saline soils
  • xerophytic shrublands

Altitude range: ~25–4300 m.

Some species tolerate frost and snow.

Distribution

South America:

  • Argentina
  • Bolivia
  • Chile
  • Peru
  • Ecuador
  • Paraguay

Taxonomy

One of the most complex genera in Cactaceae.

Key points:

  • Historically separated from Echinopsis based on floral morphology
  • Later merged into Echinopsis sensu lato (Hunt et al.)
  • Molecular studies show that Echinopsis s.l. is polyphyletic
  • Strong links with Lobivia, Soehrensia and related groups

Current interpretation:

  • Trichocereus sensu stricto is accepted
  • Helianthocereus is included within it
  • Relationships remain partially unresolved

Species

Following Joël Lodé (2015):

Additional taxa (after Albesiano 2012)

Notes

  • One of the most taxonomically debated cactus genera.
  • Strong morphological convergence complicates classification.
  • Molecular data only partially resolves relationships.
  • Closely linked to Echinopsis, Lobivia and Soehrensia.
  • Species limits remain fluid and subject to revision.