Family: Rosaceae
Acaena
Citation:
Mutis ex L., Mant. Alt. 145 (1771).
Derivation: Greek akaina, a thorn; alluding to the prickles on the fruit.
Synonymy: Not Applicable Common name: Sheeps burrs.
Description:
Perennial herbs with imparipinnate leaves and adnate stipules.
Flowers in spikes or heads; sepals usually 4 or 5, valvate, persistent; petals 0; stamens 2-10; carpels 1, rarely 2, each with a terminal style dilated into an oblique fringed stigma and 1 pendulous ovule.
Fruit a 1-seeded coriaceous achene firmly enclosed in the hollow hardened receptacle, which is almost closed at the summit and is furnished with prickles or awns barbed with reflexed hairs.
Distribution:
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About 100 species mainly in the Southern Hemisphere. (Keys and descriptions are based on A. E. Orchard (1969), Trans. R. Soc. S. Aust. 93:91-109.)
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Biology:
No text
Key to Species:
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1. Flowers and fruits all in a globular head |
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A. novae-zelandiae 4. |
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1. Flowers and fruits in an interrupted spike or mostly in a head but with 3 or 4 on the stem below |
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2. Fruits mostly in a head but with 3 or 4 on the stem below |
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A. X anserovina 2. |
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2. Fruits in interrupted spikes |
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3. Leaflets with hairs confined to the major veins and/or midrib on the lower surface |
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A. echinata 3. |
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3. Leaflets densely and evenly appressed pilose on the lower surface |
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4. Spines of the fruit more or less equal |
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A. agnipila 1. |
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4. Spines of the fruit unequal, 3-6 longer than the rest |
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A. ovina 5. |
Author:
Not yet available
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