Cornus unalaschkensis |
Cornaceae |
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alaskan bunchberry, western bunchberry, western cordilleran bunchberry |
dogwood family |
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Habit | Herbs, shrubs, or trees, perennial, deciduous, synoecious [dioecious]; hairs unbranched or 2-armed (occasionally 1 arm absent). | |
Stems | erect, green, 6–22 cm, appressed-hairy; nodes 4–6, internodes progressively longer distally; branches only at distalmost node, much shorter than distal internodes so stems appear unbranched. |
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Leaves | at proximal 2–4 nodes nonchlorophyllous, opposite, ± scalelike, caducous (rarely chlorophyllous at 3d node from apex but much smaller than more distal leaves), at 2d node from apex nonchlorophyllous proximally, chlorophyllous distally, opposite, well developed, persistent, at distalmost node chlorophyllous, appearing to be in whorl of 6, well developed, persistent; distalmost leaves much bigger than those at 2 more proximal nodes; petiole 0–3.4 mm; blade ovate to elliptic, 3.5–8 × 0.9–4 cm, apex acute or short acuminate, abaxial surface pale green, hairs sparsely appressed-hairy, adaxial surface green, appressed-hairy; secondary veins 3 per side, all arising from proximal 1/2. |
usually opposite, sometimes alternate, simple; stipules absent; petiole usually present, sometimes absent; blade margins entire; venation pinnate (eucamptodromous). |
Inflorescences | 20–40-flowered; peduncle 13–30 mm; primary branches 0–2 mm; bracts greenish white or white, often red-tipped, unequal, 2 ovate, 21–30 × 12–13 mm, 2 suborbiculate, 17–1.9 × 13–16 mm, apex acuminate. |
axillary or terminal, cymes, umbels, or capitula. |
Pedicels | 0.4–1.6 mm, sparsely appressed-hairy or glabrous. |
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Flowers | hypanthium cream to mottled purple, 1.2–2 mm, densely appressed-hairy; sepals mottled purple and cream, 0.1–0.4 mm, apex rounded or acute, thick, sparsely hairy on margin, densely glandular; petals cream proximally, purple distally, 1.5–1.8 mm, apical awn 0.4–0.6 mm; nectary dark purple or black. |
bisexual [unisexual]; perianth and androecium epigynous; hypanthium completely adnate to ovary; sepals 4(–5), distinct or slightly connate; petals 4(–5), distinct, valvate; nectary present, intrastaminal; stamens 4(–5), distinct, free; anthers dehiscing by longitudinal slits; pistil 1, [1–]2[–4]-carpellate, ovary inferior, [1–]2[–4]-locular, placentation apical; ovules 1 per locule, apotropous to epitropous; style 1; stigmas 2. |
Fruits | drupes, rarely fused into a syncarp. |
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Drupes | 10–20 per inflorescence, red, globose, 6–8 mm; stone globose or subglobose, 2.7–3.4 × 2.1–3.4 mm, longitudinally grooved, apex slightly pointed. |
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Seeds | 1(–2) per fruit. |
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2n | = 44. |
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Cornus unalaschkensis |
Cornaceae |
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Phenology | Flowering May–Aug; fruiting Aug–Oct. | |
Habitat | Maritime copse or heath, maritime coniferous forests and bog woodlands, moist broadleaf or coniferous forests. | |
Elevation | 0–3000 m. (0–9800 ft.) | |
Distribution |
AK; CA; ID; OR; WA; AB; BC; YT
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North America; Mexico; Central America; n South America; w South America; Eurasia; Africa; predominately northern boreal and temperate regions; also high elevations in subtropical and tropical regions |
Discussion | Genus 1, species ca. 60 (20 species in the flora). Delimitation of Cornaceae has varied over the years, with many treatments circumscribing the family broadly to include Nyssa and several small Asian genera along with Cornus (for example, Xiang Q. Y. et al. 1998). DNA sequence data from intensive taxon sampling support narrower circumscription, with Cornus as the sole member of the family and sister to the Asian Alangiaceae de Candolle (Xiang et al. 2011); that treatment is followed here. Aucuba, sometimes included in Cornaceae, is here placed in Garryaceae. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Source | FNA vol. 12, p. 448. | FNA vol. 12, p. 443. |
Parent taxa | ||
Sibling taxa | ||
Subordinate taxa | ||
Synonyms | Arctocrania unalaschkensis, Chamaepericlymenum unalaschkense, Cornella unalaschkensis, Swida unalaschkensis | |
Name authority | Ledebour: Fl. Ross. 2: 378. (1844) | Berchtold & J. Presl |
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