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Welwitschia family
Welwitschiaceae Caruel
ウェルウィッチア科
A gymnosperm family endemic to the Namib Desert of southwestern Africa. A monotypic family consisting of a single species, Welwitschia mirabilis. Only two leaves grow throughout the plant's entire lifespan, and individuals are estimated to live for hundreds to thousands of years.
Key Characteristics
- ●Only two leaves that grow continuously throughout life, splitting into strap-like segments
- ●Stem short and swollen into a woody, caudex-like structure
- ●Dioecious, with cone-like strobili
- ●Unique morphology adapted to extreme arid conditions
Morphological Traits
A family may include species with different trait values — multiple values indicate the range within the family.
Leaf arrangement
Opposite
Leaf type
Simple
Venation
Parallel
Leaf margin
Entire
Leaf shape
Linear
Growth form
Herb
Evergreen/Deciduous
Evergreen
Stipules
Absent
Petal fusion
No petals
Ovary position
Superior
Plant sex
Dioecious
Phylogenetic Position
Gymnosperms > Gnetophytes > Gnetales > Welwitschiaceae
Divergence Era
Jurassic to Cretaceous (ca. 130 million years ago)
Representative Genera
Related Evolution Events
- ・Divergence as an independent evolutionary lineage within the gnetophytes
- ・Extreme xerophytic adaptation to the Namib Desert
- ・Acquisition of a unique growth strategy of living with only two leaves for life
Plants in Welwitschia family on this site
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