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Arrowhead
Sagittaria trifolia
γͺγ’γγ«
A perennial herb growing in rice paddies and along waterways. Characterized by its distinctive arrowhead-shaped leaves, it is related to the Chinese arrowhead (Kuwai). White 3-petaled flowers bloom in summer. Although a troublesome rice paddy weed, its dignified leaf shape earned it the name 'Omodaka' (noble face).
Identification Points
- βLeaves are distinctively arrowhead-shaped (sagittate)
- βWhite 3-petaled flowers; male flowers above, female flowers below
- βForms underground corms
Habitat
Rice paddies, wetlands, ditches, and shallow margins of ponds
Season
AugustβOctober (flowers)
Morphological TraitsAI-estimated, needs verification
Growth form
Herb
Habitat
Aquatic
Leaf arrangement
Alternate
Leaf type
Simple
Petal count
6 petals
Flower symmetry
Actinomorphic
Ovary position
Superior
Latex
Present
Stamen count
3-4
Phylogenetic Positionγͺγ’γγ«η§ β
Phylogenetic Position
Angiosperms > Monocots > Alismatales > Alismataceae
Divergence Era
Paleogene (ca. 60β50 Ma)
Evolution Notes
Alismataceae is one of the early-diverging lineages of monocots, retaining primitive features such as trimerous flowers and numerous free carpels.
View on evolution timeline βSources & References
AI-generated, needs verification