phyllode

Latin phyllodium, from Ancient Greek φυλλώδης (phullṓdēs, “resembling a leaf”).

phyllode (plural phyllodes)

1. (botany) A flattened petiole or leaf rachis that resembles and functions as a leaf, and may or may not be combined with an actual lamina.

• phylloclade

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  Acacia koa with both lamina-supporting and laminaless phyllodes.
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  The rachis of the compound leaves of Parkinsonia aculeata is the main photosynthetic portion of the leaf; the tiny leaflets later fall
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  The leaflet stalks of this Rubus species are elongated and resemble prickly stems