Pilosocereus

Byles & G. D. Rowley

Cact. Succ. J. Gr. Brit. 19: 66. 1957.

Common names: Tree cactus
Etymology: Latin pilosus, shaggy, and Cer eus, a genus of cacti
Basionym: Pilocereus Lemaire Cact. Gen. Sp. Nov., 6. 1839, name illegitimate
Treatment appears in FNA Volume 4. Treatment on page 179. Mentioned on page 97, 180.
 TaxonIllustrator 
FNA4 P31 Pilosocereus robinii.jpegPilosocereus robinii
Bergerocactus emoryi
Pachycereus schottii
John Myers
John Myers
John Myers

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.

Distribution

Fla., Mexico, West Indies, Central America, South America

Discussion

Species ca. 40 (1 in the flora).

The name Pilosocereus was created to replace the illegitimate name Pilocereus, which was earlier applied to this genus. Cephalocereus Pfeiffer, also formerly misapplied to the North American species, is now recognized as restricted to southern Mexico (W. Barthlott and D. R. Hunt 1993; E. F. Anderson 2001), although generic boundaries continue to be the subject of debate.

... more about "Pilosocereus"
cushionlike +
confluent +, adjacent +  and spaced +
circular +  and elliptic +
deciduous +  and persistent +
hourglass--shaped +
Bruce D. Parfitt +  and Arthur C. Gibson +
Byles & G. D. Rowley +
hardened +
Pilocereus +
triangular +
not distinguishable +
proliferating +
flattened +  and cylindric +
Tree cactus +
mucilaginous +
Fla. +, Mexico +, West Indies +, Central America +  and South America +
not separating +
Latin pilosus, shaggy, and Cer eus, a genus of cacti +
6 cm60 mm <br />0.06 m <br /> (9 cm90 mm <br />0.09 m <br />) +
5 cm50 mm <br />0.05 m <br /> (7 cm70 mm <br />0.07 m <br />) +
crepuscular +  and nocturnal +
5 cm50 mm <br />0.05 m <br /> (6 cm60 mm <br />0.06 m <br />) +
lateral +  and subterminal +
15 cm150 mm <br />0.15 m <br /> (30 cm300 mm <br />0.3 m <br />) +
curved +  and straight +
0.2 cm2 mm <br />0.002 m <br /> (15 cm150 mm <br />0.15 m <br />) +
persistent +, long +  and deciduous +
clavate +, spheric +  and depressed-spheric +
dry +, fleshy +  and juicy +
0.8 cm8 mm <br />0.008 m <br /> (5 cm50 mm <br />0.05 m <br />) +
tawny +  and white +
longest +
0 cm0 mm <br />0 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
0.9 cm9 mm <br />0.009 m <br /> (2.6 cm26 mm <br />0.026 m <br />) +
deciduous +  and persistent +
rudimentary +
flat +  and terete +
nearly +  and microscopic +
0 cm0 mm <br />0 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
tuberculate +
fluted;spheric;depressed-spheric or club-shaped +
denticulate +  and entire +
deciduous +  and persistent +
mucilaginous +
ridgelike +  and nipple--shaped +
Cact. Succ. J. Gr. Brit. +
austin1984a +, hennessey1994a +, lima1996a +  and zappi1994a +
rounded +
purple +  and red +
indehiscent +
2 cm20 mm <br />0.02 m <br /> (4.5 cm45 mm <br />0.045 m <br />) +
depressed-spheric +
30mm +  and 50mm +
arillate +  and strophiolate +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
snail--shaped +
1.5 cm15 mm <br />0.015 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
purple +, red +, gray +  and yellow +
straight +
indehiscent +
deciduous +  and persistent +
20mm +  and 45mm +
6 (?) +  and 31 (?) +
depressed-spheric +, terete +  and acicular +
3 cm30 mm <br />0.03 m <br /> (5 cm50 mm <br />0.05 m <br />) +
decurrent +
unsegmented +
2.8 cm28 mm <br />0.028 m <br /> (5 cm50 mm <br />0.05 m <br />) +
green +  and bluish or blue-green +
columnar +
succulent +
5cm;8cm +
tuberculate +
adventitious +
tuberlike +
epipetric +  and epiphytic +
Pilosocereus +
Cactaceae subfam. Cactoideae +
dull +  and glossy +
plant +, shrub +  and tree +
epiphytic;epiphytic;epiphytic +
erect +  and ascending or reclining +
barrel-shaped +  and spheric +