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Nipplewort (Japanese)πΌ
Lapsanastrum apogonoides
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A small winter annual in the Asteraceae. This is the true 'hotokenoza' of Japan's seven herbs of spring, not the modern plant of the same name (which is Lamium amplexicaule in the Lamiaceae). Grows as a flat rosette on paddy edges and wet fields, with small yellow ligulate heads.
Identification Points
- βFlat rosette of leaves pressed against the ground
- βLeaves pinnately lobed, resembling a small dandelion leaf
- βFlower heads yellow, composed only of ligulate florets
- βExudes white latex when the stem is broken
Habitat
Paddy fields and rice paddy edges in Honshu, Shikoku, Kyushu
Season
March to May (flowers)
Morphological TraitsAI-estimated, needs verification
Petal count
3 petals
Ovary position
Inferior
Stamen count
1-2
Phylogenetic Positionγγ―η§ β
Phylogenetic Position
Angiosperms > Eudicots > Core eudicots > Asterales > Asteraceae
Divergence Era
Late Cretaceous to Paleogene (approx. 80β70 million years ago)
Evolution Notes
The Asteraceae underwent explosive diversification roughly 40β50 million years ago. Species in Cichorioideae such as this one take the extreme strategy of building flower heads entirely from ligulate florets. The seven-herbs 'hotokenoza' refers to this species; the modern 'hotokenoza' (Lamium amplexicaule, Lamiaceae) diverged from it roughly 100 million years ago.
View on evolution timeline βSources & References
AI-generated, needs verification