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Giant Rhubarb
Gunnera manicata
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A perennial herb native to Brazil and one of the largest-leaved herbaceous plants in the world, with leaf blades sometimes exceeding 3 m in diameter. Cultivated ornamentally in botanical gardens and parks in Japan.
Identification Points
- βLeaves enormous, 1β3+ m in diameter, orbicular to cordate
- βPetioles thick with spine-like projections
- βRhizomes harbor symbiotic cyanobacteria for nitrogen fixation
Habitat
Botanical gardens and parks (cultivated)
Season
Summer (best viewing)
Morphological TraitsAI-estimated, needs verification
Growth form
Herb
Leaf shape
Cordate
Habitat
Cultivated
Leaf arrangement
Alternate
Leaf type
Simple
Venation
Palmate
Ovary position
Inferior
Stamen count
1-2
Phylogenetic Positionγ°γ³γγ©η§ β
Phylogenetic Position
Angiosperms > Eudicots > Core eudicots > Gunnerales > Gunneraceae
Divergence Era
Late Cretaceous to Paleogene (approx. 80 million years ago)
Evolution Notes
Gunneraceae is the only known angiosperm family to form nitrogen-fixing symbiosis with cyanobacteria (Nostoc), drawing attention for parallel evolution with nitrogen-fixing systems in bryophytes.
View on evolution timeline βSources & References
AI-generated, needs verification