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Birthwort
Aristolochia debilis
ウマノスズクサ
A climbing perennial herb of meadows and roadsides. It bears distinctively shaped tubular flowers and is known as the larval food plant of the Chinese Windmill butterfly (Atrophaneura alcinous). The entire plant contains toxic aristolochic acid.
Identification Points
- ✓Flowers are yellowish-green, U-shaped pipe form with internal hairs
- ✓Leaves heart-shaped to triangular, somewhat leathery
- ✓Fruit is a pear-shaped capsule that splits into 6 segments when ripe, releasing seeds
Habitat
Levees, riverbanks, roadsides, and grasslands
Season
July–September (flowers)
Morphological TraitsAI-estimated, needs verification
Growth form
Vine
Leaf dissection
Dissected
Leaf shape
Cordate
Leaf arrangement
Alternate
Leaf type
Simple
Stipules
Absent
Plant sex
Hermaphrodite
Stamen count
3-4
Phylogenetic Positionウマノスズクサ科 →
Phylogenetic Position
Angiosperms > Magnoliids > Piperales > Aristolochiaceae
Divergence Era
Late Cretaceous (ca. 90 Ma onwards)
Evolution Notes
Aristolochiaceae is a member of the magnoliids (basal angiosperms). Internal hairs of the tubular flowers temporarily trap insects to ensure pollen transfer—a trap-flower mechanism.
View on evolution timeline →Sources & References
AI-generated, needs verification