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Family:
Cactaceae (Cactus
Family)
Scientific Name:Pelecyphora aselliformis Ehrenberg 1843
Origin:
Garden origin
(Nursery produced cultivar)
Conservation status: Listed in
CITES appendix I
The
cause of cresting: The cause of cresting is not fully explained, biologists
disagree as to why some saguaros grow in this unusual form. Some
speculate that it is a genetic mutation. Others say it is the result of
a lightning strike or freeze damage, but whatever the stimulus, the
growth point of the stem has switched from a geometric point, to a line,
which folds and undulates as the crest expands. Crested
pelecyphore are somewhat rare (1 in 250,000) and can be encountered in many
other cactus species.
In the
ontogenesis
a crest can appear any time, but development of crests at large
columnar
cactus species ( such as in saguaro Carnegia gigantea) in the
early
stages
of ontogenesis is unlikely. On the other hand small species may crest
early already at the
cotyledons
stage.
Photo of
conspecific taxa, varieties, forms and cultivars of
Pelecyphora
aselliformis:
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