Harrisia

Harrisia
File:Harrisia martinii.jpg
Kingdom	Plantae
Family	Cactaceae
Subfamily	Cactoideae
Tribe	Cereeae
SubTribe	Trichocereinae
Genus	Harrisia
Species
Notes	Taxonomy follows Joël Lodé (2015). Lodé divides the genus into three subgenera: Harrisia, Eriocereus, and Roseocereus.

Etymology

The genus is named in honor of William Harris (1860–1920), an Irish botanist who served as the Superintendent of Public Gardens and Plantations in Jamaica.

Description

Harrisia consists of night-blooming cacti with slender, cylindrical stems that can be erect, decumbent, or climbing.

• Stems: Typically have few ribs (3 to 11) and lack a cephalium.
• Flowers: Large, nocturnal, funnel-shaped, and usually white. They feature a long floral tube covered with scales and often hair or wool, but never spines (distinguishing them from Echinopsis).
• Fruits: Globose to ovoid, fleshy, and often brightly colored (red or yellow). They may be smooth or tuberculate and sometimes feature deciduous scales.
• Seeds: Relatively large, black, and rough or pitted.

Habitat

The genus has a disjunct distribution. It grows in tropical dry forests, coastal scrubs (Caribbean), and chaco shrublands (South America). Altitudinal range: 0–1500 m.

Distribution

• Caribbean & North America: Florida (USA), Bahamas, Cuba, Cayman Islands, Dominican Republic, Haiti, Jamaica, Puerto Rico.
• South America: Argentina, Bolivia, Brazil, Paraguay, Uruguay.

Species and Subspecies

Following Lodé (2015), 20 species and 2 subspecies are recognized:

• Harrisia aboriginum
• Harrisia adscendens
• Harrisia bonplandii
• Harrisia brookii
• Harrisia caymanensis
• Harrisia divaricata
• Harrisia earlei
• Harrisia eriophora
• Harrisia fernowii
• Harrisia fragrans
• Harrisia gracilis
• Harrisia martinii
• Harrisia pomanensis
  • Harrisia pomanensis subsp. bonplandii (Note: Often listed as a species, Lodé treats it here)
  • Harrisia pomanensis subsp. regelii
• Harrisia portoricensis
• Harrisia simpsonii
• Harrisia taetra
• Harrisia taylorii
• Harrisia tetracantha (formerly Roseocereus)
• Harrisia tortuosa

Taxonomy

Lodé maintains Harrisia as a distinct genus within the tribe Cereeae. He rejects the merging of these species into Echinopsis, noting clear differences in seed morphology and floral structure. The inclusion of the Bolivian genus Roseocereus (as H. tetracantha) is supported by molecular data.