• ETYMOLOGY
“Isolated candle”, because the populations of the genus are very scattered, well separated and isolated from each
other. • DESCRIPTION
A genus of treelike plants, columnar, heavily branched, developing a short trunk. Stems with few ribs (5-7), areoles close-set, spines aciculate.
Flowers nocturnal, self-sterile, remaining open the following morning, numerous, appearing in chains on the tallest stems, tubular, white with outer tepals reddish, pollinated by bats (Choeronycteris mexicana, Leptonycteris curasoae, L. nivalis). Fruits egg-shaped, unarmed, red – orange with red pulp, dehiscent. Seeds small, elongated, warty, shiny, black. • HABITAT
The monotypic genus Isolatocereus grows endemically in Central Mexico, in valleys or on hills of basalt, forming true forests, in a vegetation of matorral, between 300 m and 2300 m in altitude. It is used locally for making quickset hedges. • DISTRIBUTION
Mexico (Aguascalientes, Guanajuato, Guerrero, Hidalgo, Jalisco, Mexico D.F., Michoacan, Morelos, Oaxaca, Puebla, Queretaro, San Luis Potosi, Veracruz, Zacatecas).
Currently only one recognised species:
– Isolatocereus dumortieri* (Scheidw.) Backeb. 1942
• ETYMOLOGY
Genus native of the province of Islay, department of Arequipa, in Peru, where the genus was first found. • DESCRIPTION
A genus of globose to shortly cylindrical plants, the apex wooly, with fibrous roots or turbiniform. Thick central spines and undefined radials.
Flowers diurnal, sometimes self-fertile, pale yellow to sulphur yellow, pollinated by hymenoptera. Fruits clavate to elongated like a balloon, hollow, thin-walled, pink to red. Seeds black, subglobose, tuberculate, covered with mucilage. • HABITAT
The genus Islaya grows between Peru and Chile, along the Pacific coast, an extremely arid area, in full sun, on very poor mineral soils, sandy or even gypsum (clastic sediments), but takes advantage of the coastal fog, the garъa in Peru, or the camanchaca in Chile. It is found from sea level up to 1050 m in altitude. Some species such as Islaya islayensis are in great danger of extinction, probably due to climate change. • DISTRIBUTION
Chile (Antofagasta, Tarapaca), Peru (Arequipa, Moquegua, Lima, Tacna).
Currently 5 species + and possible subspecies:
– Islaya Iquiquensis (F.Ritter) Faundez & R.Kiesling 2007
– Islaya islayensis* (Foster) Backeb. 1934
– Islaya mollendensis Backeberg 1935
– Islaya omasensis Ostolaza & Mischler 1983
– Islaya unguispina F.Ritter 1981
• ETYMOLOGY
“candle of the forest”, defining the habitat of the genus, which are in fact dry forests with seasonal rainfall. • DESCRIPTION
A genus of epiphytic or climbing plants, sturdy, strongly branched, with creeping stems usually three-angled, segmented, sometimes exceeding 10 m long and producing aerial roots. Areoles slightly woolly, spines very short, few, sometimes absent.
Flowers nocturnal, self-sterile, very large (the largest of all the family of Cactaceae is H. calcaratus with 30cm in diameter), funnel-shaped, with a sturdy floral tube, white (rarely red), pollinated by bats (Artibeus jamaicensis and A. lituratus for H. lemairei and Choeronycteris mexicana, Leptonycteris curasoae and L. yerbabuenae for H. undatus) and sphingideae (H. costaricensis according to Harber 1983, in Emerson 2007). Fruits globose to elongated, large, fleshy, edible, usually red but also yellow or orange, covered with wide, soft, flexible and sharp scales, opening irregularly when mature, retaining or not the remains of the dried out perianth. Seeds rather large, more or less droplet-shaped, brown. • HABITAT
The genus Hylocereus grows mostly in the shade, in dry or rainforests, semi-epiphytic, climbing to the trees by using aerial roots, or on rocks, from sea level up to 2200 m in altitude. • DISTRIBUTION
Antigua, Argentina (Corrientes, Misiones), Barbardos, Belize, Bolivia, Brazil (Bahia, Espirito Santo, Goias, Mato Grosso, Minas Gerais, Para, Parana, Pernambuco, Rio de Janeiro), Colombia (Bolivar, Cundinamarca, Guajira, Magdalena, Santander, Vaupes), Costa Rica (Alajuela, Guanacaste, Heredia, Limon, Puntarenas, San Jose), Cuba, Dominican Republic, Ecuador (Azuay, Chimborazo, Concepcion, El Oro, Guayas, Loja, Los Rios, Manabi), Grenadines (Bequia), Guatemala (Alta + Baja Verapaz, Chimaltenango, Chiquimula, El Progreso, Escuintla, Guatemala, Huehuetenango, Izabal, Jutiapa, Peten, Quetzaltenango, Quiche, Retalhuleu, San Marcos, Santa Rosa, Suchitepequez, Zacapa), Grenada, Guyana, French Guyana, Haiti, Honduras (Atlantida, Yoro), Virgin Islands, Jamaica, Mexico (Chiapas, Colima, Distrito Federal, Guerrero, Jalisco, Michoacan, Nayarit, Sinaloa, Veracruz, Yucatan?) Montserrat, Nicaragua, Panama (Veraguas), Paraguay, (Concepcion, Paraguari, Presidente Hayes), Peru (Amazonas, Huanuco, Jaen, Junin, Lambayeque, Loreto, Piura, San Martin, Tumbes), Puerto Rico, Saba, St Eustache, St Vincent, Surinam (Brokopondo), Trinidad and Tobago, Venezuela (Anzoategui, Bolivar, Carabobo, Cojedes, Delta Amacuro, Distrito Federal, Falcon, Guarico, Lara, Portuguesa, Sucre, Zulia). Hylocereus undatus is grown worldwide in tropical area, especially in southeast Asia for its fruits (dragon fruit). Its origin is uncertain.
Currently 15 recognised species + one subspecies:
– Hylocereus calcaratus (F.A.C.Weber) Britton & Rose 1909
– Hylocereus costaricensls* (F.A.C.Weber) Britton & Rose 1909
– Hylocereus escuintlensis* Kimnach 1984
– Hylocereus extensus* (Salm-Dyck ex D.C.) Britton & Rose 1920 (ex Selenicereus)
– Hylocereus guatemalensls* (Eichlam) Britton & Rose 1920
– Hylocereus megalanthus* (Vaupel) Bauer 2003 (ex Mediocactus)
– Hylocereus microcladus Backeberg 1942
– Hylocereus mlnutiflorus Britton & Rose 1913 (ex Wilmattea)
– Hylocereus monacanthus* (Lem.) Britton & Rose 1920 (incl. H. venezuelensis)
– Hylocereus ocamponis* (Salm-Dyck) Britton & Rose 1909 (= H. purpusii)
– Hylocereus setaceus* (D.C.) Bauer 2003 (ex Selenicereus)
– Hylocereus stenopterus (F.A.C.Weber) Britton & Rose 1909
– Hylocereus triangularis* (L.) Britton & Rose 1909
– Hylocereus tricae* (Hunt) Bauer 2003 (ex Selenicereus)
– Hylocereus undatus* (Haw.) Britton & Rose 1918
– Hylocereus undatus subsp. luteocarpus Calix 2005
• ETYMOLOGY
“Candle of the sun” referring to the flowers, which are diurnal. • DESCRIPTION
Genus of bushy, epiphytic or saxicolous plants, with long prostrate or climbing stems; few ribs and spines, the latter can be setose to subulate, usually rather insignificant.
Flowers diurnal, self-sterile, solitary, large, lasting for several days, funnel-shaped, orange to purple red, rarely white, pollinated by hummingbirds. Fruits globose to egg-shaped, fleshy, spiny. Seeds brown-blackish, shiny, finely pitted, covered by mucilage. • HABITAT
The genus Heliocereus grows in savannas or mesophilous and ombrophilous rainforests consisting among others of oaks (Quercus sp.), in accumulations of humus, between rocks (epilithic or saxicolous), or on trees (epiphytic), between 1500 m and 2000 m in altitude. • DISTRIBUTION
El Salvador (La Libertad, Sonsonate), Guatemala (Quetzaltenango), Honduras, Mexico (Chiapas, Colima, Durango, Estado de Mexico, Guerrero, Jalisco, Michoacan, Morelos, Nayarit, Oaxaca, Sinaloa) Nicaragua (Jinotega).
Currently 4 recognised species:
– Heliocereus aurantiacus Kimnach 1974
– Heliocereus cinnabarinus (Eichlam ex Weing.) Britton & Rose 1920
– Heliocereus lodei (M.Veliz, L.Velasquez & R.Puente) M.Veliz 2015
– Heliocereus speciosus* (Cav.) Britton & Rose 1909
• ETYMOLOGY
Genus honouring Thomas Hariot (also written Harriot, 1560-1621), English mathematician, astronomer and naturalist (see picture above). Hariota having been invalidated, Britton & Rose created the name from an anagram of Hariot, Hatiora (see portrait above, public domain). • DESCRIPTION
A genus of epiphytic or more rarely lithophytic plants, strongly branched, at first erect then pendulous, with short segments well determined, cylindrical or bottle-shaped, not tuberculate and acrotonic. Areoles tiny, spines usually absent or setose when present.
Flowers diurnal, self-sterile, appearing at the tip of stems, heteromorphic, with a very short floral tube, bell-shaped, yellow to yellow orange-coloured, or pink, pollinated by insects. Pericarpel rounded, naked. Fruits small, spherical, naked. Seeds small, shiny, brown or black. • HABITAT
The genus Hatiora grows in ombrophilous rainforests of southern Brazil, as epiphytic, taking advantage of some organic matter deposited in the hollows of trunks and branches, from 300 m up to 1500 m in altitude. This region has a significant atmospheric humidity. • DISTRIBUTION
Brazil (Bahia, Espirito Santo, Minas Gerais, Parana, Rio de Janeiro, Sao Paulo).
Currently 3 recognised species:
– Hatiora cylindrica* Britton & Rose Britton & Rose 1923
– Hatiora herminiae* (Porto & A.Cast.) Backeb. ex Barthlott 1987
– Hatiora salicornioides* (Haworth) Britton & Rose ex L.H.Bailey 1915
