Autor: Byles & Rowley

“Hairy Cereus”, referring to the abundant pilosity of the pseudocephalium that most species of the genus carry.
A genus of columnar shrubby or treelike plants, usually strongly branched, candelabriform, reaching up to 10 m high, with stems containing mucilage; epidermis usually smooth, grey-green to bluish more or less glaucous. Ribs 3 to 30, straight, often having a transverse groove under the areole; areoles felted and strongly woolly in the reproductive area, turning into, in some species, a rather longitudinal or lateral cephalium. Spines variable in number and size, mostly straight, aciculate, sometimes translucent.
Flowers nocturnal, self-sterile, tubular to bell-shaped, with a naked tube, white, greenish white to more or less intense pink, pollinated by bats (Anoura geoffroyi, Choeronycteris mexicana, Glossophaga commissarisi, G. leachii, G. longisrostris, G. soricina, Leptonycteris curasoae, L nivalis, L. yerbabuenae, Lonchophylla mordax, Phyllostomus discolor, Sturnira lilium), but also by Sphingideae (Agrius cingulatus, Cocytius antaeus, Erinnyis alope, E. ello ello, E. swairsoni and Manduca rustica), and for the flowers which remain open during the day, visits can be made by bees (Agapostemon sp, Apis mellifera, Halictus sp, Scaptotringona sp, Trigona spinipes, Xylocopa grlsescens), hummingbirds (Amazilia shone, Chlorostilbon aureoventris, Cynanthus latirostris, Heliomaster constanti, H. squamosus and Phaetornls gounellei) or other birds (Icterus gularis, I. pustulatus, Melanerpes aurifrons, Phaetornis superciliosus) and a butterfly (Hamadryas sp,). Fruits more or less globose-flattened, thick-walled, with semicircula and irregular dehiscence, exposing a white or coloured, pink to purple, compact pulp, retaining the remnants of the darkened perianth. Seeds broadly ovate to cochleariform (spoon-shaped), shiny, dark brown to black, striate. Dispersal is ornithophilous (Almophila ruficauda, Aratinga canicularis, Calocitta formosa, Campylorhynchus rufinucha, Crotophaga sulcirostris, Dives dives, Heliomaster constantii, Icterus gularis, I. pustulatus, Melanerpes aurifrons, Mimus gilvus, Passerina versicolor, Quiscalus mexicanus, Zenaida asiatica), also myrmecophilous.
The genus Pilosocereus grows In a wide geographic distribution area, from South America up to Mexico, through southeastern United States and the Caribbean islands, and grows among shrubs and bushes, in deciduous spiny dry forests, mountains, on slopes in tropical valleys, on sandy or rocky soils, sometimes on limestone outcrops, sandstone, granitic, gneissic cliffs or quartz sands, in the campo rupestre (in Brazil, mountainous subtropical savanna), In the caatinga (spiny dry forest of the Brazilian nordeste), from sea level (P. catingicola) up to 1900 m in altitude (P. chrysacanthus), often accompanied with other cacti and succulents.
Carribbean islands (Antigua, Aruba, Bahamas, Barbados, Bonaire, Cayman Islands, Curacao, La Desirade, Grenadines, Guadeloupe, Marie Galante, Martinique, Monserrat, Nevis, Saba, Saint Barthelemy, Saint Eustatius, St Kitts, St Lucia, Saint Martin, Trinidad and Tobago, Virgin Islands), Belize, Brazil (Alagoas, Bahia, Ceara, Espirito Santo, Goias, Maranhao, Mato Grosso, Mato Grosso do Sul, Minas Gerais, Paraiba, Pernambuco, Piaui, Rio de Janeiro, Rio Grande do Norte, Rondonla, Roraima, Sao Paulo, Sergipe, Tocantins), Colombia (Cauca, Cesar, Guajira, Magdalena), Cuba (Guantanamo, Santiago de Cuba), El Salvador, Ecuador (Azuay, El Oro, Guayas, Manabi), Guatemala (Baja Verapaz, El Progreso, El Quiche, Chiquimula, Huehuetenango, Santa Rosa, Zacapa), Guyana, Haiti, Honduras, Jamaica, Mexico (Chiapas, Chihuahua, Colima, Durango, Guerrero, Hidalgo, Jalisco, Mexico, Michoacan, Nayarit, Nuevo Leon, Oaxaca, Puebla, Queretaro, San Luis Potosi, Sinaloa, Sonora, Tamaulipas, Veracruz, Yucatan), Paraguay (Amambay, Concepcion), Peru (Piura, Tumbes), Puerto Rico, Dominican Republic (Pedernales), USA (Florida), Venezuela (Bolivar, Falcon, Lara, Merida, Tachlra, Trujillo).

Currently 52 recognised species + 11 subspecies:
– Pilosocereus albisummus Braun & Esteves 1987
– Pilosocereus alensis* (Weber ex Gosselin) Byles & Rowley 1957
– Pilosocereus arrabidae (Lem.) Byles & Rowley 1957
– Pilosocereus aureispinus* (Burning & Brederoo) Ritter 1979
– Pilosocereus aurisetus (Werderm.) Byles & Rowley 1957
– Pilosocereus aurisetus subsp. aurilanatus (F. Ritter) Zappi 1994
– Pilosocereus azulensis Taylor & Zappi 1997
– Pilosocereus bohlei Hofacker 2001
– Pilosocereus brasiliensis (Britton & Rose) Backeberg 1960
– Pilosocereus brasiliensis subsp. ruschianus (Burning & Brederoo) Zappi 1994
– Pilosocereus catingicola (Gurke) Byles & Rowley 1957
– Pilosocereus catingicola subsp. salvadorensis (Werderm.) Zappi 1994
– Pilosocereus chrysacanthus* (Weber) Byles & Rowley 1957
– Pilosocereus chrysostele (Vaupel) Byles & Rowley 1957
– Pilosocereus collinsii (Britton & Rose) Byles & Rowley 1957
– Pilosocereus densiareolatus Ritter 1979
– Pilosocereus densivillosus Braun & Esteves) 1994
– Pilosocereus diersianus (Esteves) Braun 1988
– Pilosocereus estevesii Braun 1999
– Pilosocereus flavipulvinatus (Burning & Brederoo) Ritter 1980
– Pilosocereus flexibilispinus Braun & Esteves 1990
– Pilosocereus floccosus* Byles & Rowley 1957
– Pilosocereus floccosus subsp. quadricostatus (Ritter) Zappi 1994
– Pilosocereus frewenii Zappi & Taylor 2011
– Pilosocereus fulvilanatus* (Burning & Brederoo) Ritter 1979
– Pilosocereus fulvilanatus subsp. rosae (Braun) Zappi 1994
– Pilosocereus glaucochrous (Werderm.) Byles & Rowley 1957
– Pilosocereus goianus Braun & Esteves 2002
– Pilosocereus gounellei (Weber) Byles & Rowley 1957
– Pilosocereus gounellei subsp. zehntneri (Britton & Rose) Zappi 1994
– Pilosocereus hermii P.J.Braun, Esteves & Hofacker 2007
– Pilosocereus jauruensis (Burning & Brederoo) Braun 1984
– Pilosocereus lanuginosus (Linne) Byles & Rowley 1957
– Pilosocereus lanuginosus subsp. colombianus (Rose) Guiggi 2010
– Pilosocereus lanuginosus subsp. moritzianus (Otto ex Pfeiffer) Guiggi 2010
– Pilosocereus lanuginosus subsp. tillianus (Gruber & Schatzl) Guiggi 2010
– Pilosocereus leucocephalus* (Poselger) Byles & Rowley 1957
– Pilosocereus lindanus Braun & Esteves 1987
– Pilosocereus machrisii* (Dawson) Backeberg 1960
– Pilosocereus magnificus (Burning & Brederoo) Ritter 1979
– Pilosocereus mollispinus Braun & Esteves 2004
– Pilosocereus multicostatus Ritter 1979
– Pilosocereus occultiflorus Braun & Esteves 1999 (not a hybr. as stated by Taylor & Zappi 2004)
– Pilosocereus oligolepis (Vaupel) Byles & Rowley 1957
– Pilosocereus pachycladus* Ritter 1979 (= P. azureus? = P. glaucescens?)
– Pilosocereus pachycladus subsp. pernambucoensis (Ritter) Zappi 1994
– Pilosocereus panchesiorum Xhonneux 2011
– Pilosocereus parvus (Diers & Esteves) Braun 1988
– Pilosocereus pentaedrophorus (Cels) Byles & Rowley 1957
– Pilosocereus pentaedrophorus subsp. robustus Zappi 1994
– Pilosocereus piauhyensis (Gurke) Byles & Rowley 1957
– Pilosocereus polygonus (Lam.) Byles & Rowley 1957 = (P. brooksianus?)
– Pilosocereus pseudosuperfloccosus Braun & Esteves 2009
– Pilosocereus purpusii* (Britton & Rose) Byles & Rowley 1957
– Pilosocereus pusillibaccatus Braun & Esteves 1979
– Pilosocereus quadricentralis (Dawson) Backeberg 1960
– Pilosocereus rizzoanus Braun & Esteves 1992
– Pilosocereus royenii* (Linne) Byles & Rowley 1957 (= P. nobilis)
– Pilosocereus splendidus Ritter 1979
– Pilosocereus tillianus Gruber & Schatzl 1982
– Pilosocereus tuberculatus (Werderm.) Byles & Rowley 1957
– Pilosocereus tuberculosus Rauh & Backeberg 1957
– Pilosocereus ulei (K. Schumann) Byles & Rowley 1957
– Pilosocereus vilaboensis* (Dlers & Esteves) Braun 1988

References: "TAXONOMY of the CACTACEAE" -  ISBN 978-84-617-3692-8 (Vol. 2)