Proc. Amer. Assoc. Advancem. Sci. 4: 192. 1851.

Common names: California tree-anemone
EndemicConservation concern
Etymology: For William Marbury Carpenter, 1811–1848, Louisiana physician and botanist
Treatment appears in FNA Volume 12. Treatment on page 485. Mentioned on page 462, 463, 474.

Shrubs. Stems erect, ascending, or spreading. Bark exfoliating in grayish sheets or strips. Branches ascending or spreading; twigs with simple trichomes. Leaves persistent, opposite; petiole present; blade lanceolate to narrowly elliptic or oblong, herbaceous to coriaceous, margins entire or obscurely denticulate, usually revolute, sometimes plane; venation pinnate. Inflorescences terminal or axillary, cymes, 3–9(–13)-flowered; peduncle present. Pedicels present. Flowers bisexual; perianth and androecium nearly hypogynous; hypanthium adnate to ovary proximally, free distally, patelliform, not ribbed in fruit; sepals persistent, 5–7, spreading, ovate to ovate-lanceolate or triangular, sparsely to densely appressed-pubescent abaxially; petals 5–7(–8), imbricate, spreading to reflexed, white, ovate, round, or depressed-elliptic, base sessile or obscurely clawed, surfaces glabrous; stamens 150–200; filaments distinct, essentially terete, not noticeably tapered from base to apex, apex not 2-lobed; anthers depressed-ovate; pistil 5–7-carpellate, ovary nearly superior, 5–7-locular; placentation axile proximally, parietal distally; style persistent, 1. Capsules conic to depressed-spheric, corticate to coriaceous, dehiscence basipetally septicidal to near base of fruit, delayed apically by persistent style. Seeds 50 per locule, brown or reddish brown, ellipsoid. x = 10.


Species 1.

Phylogenetic analyses place Carpenteria as sister to Philadelphus (L. Hufford 1997; D. E. Soltis et al. 1995) or as a clade nested within a paraphyletic Philadelphus (Guo Y. L. et al. 2013). Androecium development in the two genera is unique in Hydrangeaceae (Hufford 1998).