Pilosocereus Byles & G.D. Rowley
  • Cact. Succ. J. Gr. Brit. 19(3): 66. 1957.
  • Tree cactus [Latin pilosus, shaggy, and Cereus, a genus of cacti]

Cite taxon page as 'WFO (2021): Pilosocereus Byles & G.D. Rowley. Published on the Internet;http://www.worldfloraonline.org/taxon/wfo-4000029708. Accessed on: 06 Mar 2021'

General Information

Trees or shrubs, erect to ascending or reclining, usually branched in basal portion, older plants with closely parallel, erect branches forming narrow crown; trunk absent or present, 8-12+ cm diam. Roots diffuse. Stems unsegmented, green to bluish or blue-green, columnar, [0.5-]3-10 m × [2.8-]5-8 cm, glabrous; ribs 3-30, low, rounded, furrows straight [or wavy], rib crests sometimes notched between areoles [ribs strongly tuberculate in 1 Brazilian species]; areoles usually closely spaced along ribs [often confluent in flowering region], circular to elliptic, woolly; hairs usually white or tawny [to blackish] soft, to 8[-50] mm, longest on flower-producing areoles along each rib or on one side of stem in distal region; areolar glands not apparent; cortex and pith extremely mucilaginous. Spines 6-31 per areole, yellow [to brown or black], often aging gray, acicular, straight, terete, [2-]10-15(-25)[-40] × 0.25 mm, smooth; radial and central spines not distinguishable. Flowers nocturnal or crepuscular, lateral to subterminal on stems, from closely adjacent or confluent areoles, funnelform to narrowly campanulate, [2.5-]5-6[-9] × 2-5[-7] cm; flower tube straight or slightly curved; outer tepals greenish [blue, red, or purplish], margins entire or minutely denticulate; inner tepals white [pinkish to reddish], 9-26 × 7.5 mm, margins entire; ovary smooth, scales absent (or 1-2), spines absent; stigma lobes usually 8-12. Fruits dehiscent along 1 side or apparently indehiscent, red or purple [to blue-green], [spheric or] depressed-spheric [to ovoid or oblong], 20-45 × 30-50 mm, fleshy, scales and spines absent (rarely 1-2 scales); pulp color variable; floral remnant usually persistent. Seeds black or dark brown, snail-shaped, 1.2-2.6 mm, smooth, shiny; testa cells flat. x = 11.

  • Provided by: [D].Flora of North America @ efloras.org
    • Source: [
    • 1
    • ]. 

    PILOSOCEREUS Byles & G.D. Rowley

  • Provided by: [C].Flora de Nicaragua
    • Source: [
    • 2
    • ]. 



    Austin, D. F. 1984. Resumé of the Florida taxa of Cereus (Cactaceae). Florida Sci. 47: 65-68. Hennessey, M. K. and D. H. Habeck. 1994. Observations on reproduction of an endangered cactus, Cereus robinii (Lemaire) L. Benson. Florida Sci. 57: 93-101. Lima, A. N. and R. M. Adams. 1996. The distribution and abundance of Pilosocereus robinii (Lemaire) Byles and Rowley in the Florida Keys. Bradleya 14: 57-62. Zappi, D. C. 1994. Pilosocereus (Cactaceae): The Genus in Brazil. Sherborne.

  • Provided by: [D].Flora of North America @ efloras.org
    • Source: [
    • 1
    • ]. 

    Included Species

    Other Local Names

    Tree cactus [Latin pilosus, shaggy, and Cereus, a genus of cacti]

     Information From

    World Flora Online Data. 2017.
    • A CC0 1.0 Universal (CC0 1.0).
    MBG Floras Images
    Flora images. Missouri Botanical Garden. Accessed on Jun. 2018.
    • B Missouri Botanical Garden
    Flora de Nicaragua
    WD Stevens, CU Ulloa, A Pool and OM Montiel. Missouri Botanical Garden Press, 2001
    • C Missouri Botanical Garden
    Flora of North America @ efloras.org
    'Flora of North America @ eFloras (2008). Published on the Internet http://www.efloras.org/flora_page.aspx?flora_id=1 [accessed August 2016]' Missouri Botanical Garden, St. Louis, MO & Harvard University Herbaria, Cambridge, MA.
    • D Flora of North America Association
    World Flora Online consortium
    World Flora Online Data. 2018.
    • E CC0 1.0 Universal (CC0 1.0).