Directory       News       Site Map       Home
         
    Jepson eFlora
Key to families | Table of families and genera

Specimen numbers are hyperlinked to records in the Consortium of California Herbaria data view where possible. Taxa are hyperlinked to entries in the Jepson Interchange via the "[Online Interchange]" link.

 

ACAENA

B.H. Macmillan & Barbara Ertter


Perennial herb, nonglandular. Leaf: generally ± basal, odd-1-pinnate; leaflets ± evenly toothed to lobed. Inflorescence: dense spike or head; pedicel bractlets 0. Flower: hypanthium ± obconic, bractlets leaf-like to linear; sepals generally 4; petals 0; stamens 2 or 4, opposite sepals; pistils 1(2), ovary superior, continuous to style at top, stigma many-branched, exserted from hypanthium. Fruit: hypanthium ± hardened, encasing elliptic achenes; prickles generally 4–many, generally barbed.
± 45 species: especially southern hemisphere. (Greek: thorn, from fruit)
Unabridged references: [Webb et al. 1988 Flora of New Zealand Vol 4]

Key to Acaena

1. Inflorescence a spike; hypanthium prickles in fruit > 4, longest generally 1–3 mm, ± throughout; plant from ± woody, branched caudex; leaflets pinnately dissected ..... A. pinnatifida var. californica

1' Inflorescence a head; hypanthium prickles in fruit 4, longest 7.5–15 mm, ± on top; plant from stolons; leaflets toothed

2. Hypanthium in fruit with longest prickle 7.5–12 mm, without vestigial prickles below top; stem 1–2 mm diam; leaflets dull, smooth adaxially, generally ± glaucous abaxially ..... A. novae-zelandiae

2' Hypanthium in fruit with longest prickle 9–15 mm, generally with a few vestigial prickles below top; stem 2–3 mm diam; leaflets shiny, wrinkled adaxially, pale with uneven wax layer abaxially ..... A. pallida

Contact/Feedback

Citation for the whole project: Jepson Flora Project (eds.) [year] Jepson eFlora, http://ucjeps.berkeley.edu/IJM.html [accessed on month, day, year]
Citation for an individual treatment: [Author of taxon treatment] [year]. [Taxon name] in Jepson Flora Project (eds.) Jepson eFlora, [URL for treatment]. Accessed on [month, day, year].
We encourage links to these pages, but the content may not be downloaded for reposting, repackaging, redistributing, or sale in any form, without written permission from The Jepson Herbarium.