Crataegus rivularis |
Crataegus ursopedensis |
|
---|---|---|
mountain river hawthorn, river hawthorn |
bear's paw hawthorn |
|
Habit | Shrubs or trees, 30–50 dm. | Shrubs, 20–30(–40) dm. |
Stems | twigs: new growth greenish, sparsely pubescent, early glabrescent, 1–2-years old often red-purple; bark on younger 2–5 cm thick branches dark gray-brown, sometimes copper-colored; thorns on twigs straight or ± recurved, 2-years old black or purple-black, glossy, fine, 1.5–4 cm. |
expanding bud-scales orange-tan or paler; twigs: new growth pubescent, 1-year old shiny red-brown, 2-years old red-brown with white flakes, older gray; thorns on twigs usually numerous, ± straight to recurved, 2-years old shiny, very dark red-brown, ± stout, (3–)4–7 cm. |
Leaves | petiole 1–2.5 cm, glabrous; blade elliptic to narrowly elliptic, 3–8 cm, length 2+ times width, thin, base cuneate, lobes 0 or small apiculi at ends of some vein tips, margins serrate, teeth numerous, usually acute, fine to coarse, venation semicamptodromous, veins 4 or 5 per side, larger often branched proximal to ends, apex acute, abaxial surface glabrous, adaxial appressed-strigose young. |
petiole length 30–45% blade, glabrous (adaxial sulcus hairy mature), densely sessile-glandular; blade ovate to ovate-trullate, 5.5–9.5 cm (flabellate, 2–3 cm at early anthesis), subcoriaceous, base cuneate to narrowly cuneate, lobes 4 or 5 per side, sinuses deep (max LII 25–35%), lobe apex acute to acuminate, margins ± serrate, teeth numerous, small, veins 5 per side, apex acuminate, glossy, abaxial surface glabrous, main veins sometimes sparsely to moderately pubescent young, adaxial densely scabrous young, glabrate mature. |
Inflorescences | 6–12-flowered; branches glandular-punctate; bracteoles early caducous, usually present, margins sessile-glandular. |
(1–)5–12-flowered, widely spread at full anthesis; branches moderately pubescent; bracteoles cream to pale green, often suffused light red especially distally, narrowly elliptic, membranous, margins densely sessile-glandular, appearing to grade into bud scales. |
Flowers | 14–17 mm diam.; sepals broadly deltate, 6–8 mm, margins entire, apex narrow, glabrous; stamens 10, anthers pink, sometimes ivory; styles 3–5. |
15–18 mm diam.; hypanthium exterior pubescent, interior glabrous; sepals pale green to scarious, triangular, 4–5 mm, margins glandular or glandular-denticulate, abaxially glabrous, adaxially sparsely hairy; stamens 10, anthers ivory; styles 3 or 4. |
Pomes | deep red (mid Aug), black or blackish purple mature, suborbicular, 10 mm diam.; sepals ± erect to strongly outcurved or ± patent, 2–3 mm; pyrenes 3 or 4, sides eroded. |
1–8 mm; branches pubescent, sometimes sparsely; orange-red young, becoming orange-red to bright red, ellipsoid or oblong, 8–11 mm tall, pubescent; sepals spreading to ± appressed, 3–4 mm; pyrenes 3 or 4, sides plane to shallowly concave. |
Crataegus rivularis |
Crataegus ursopedensis |
|
Phenology | Flowering mid May–early Jun; fruiting Aug–Sep. | Flowering May–Jun; fruiting not recorded. |
Habitat | Intermontane streamsides, ditches, flood plains | Thickets, shade of aspen or poplar |
Elevation | 1300–2300 m (4300–7500 ft) | 800–1300 m (2600–4300 ft) |
Distribution |
AZ; CO; ID; NM; NV; UT; WY
|
MT; AB; SK |
Discussion | Crataegus rivularis is most abundant in intermontane Colorado and Utah and is one of two hawthorns found in Arizona; it is rare in Nevada. There are reports from northwestern Texas (for example, D. S. Correll and M. C. Johnston 1970); they have not been verified. Crataegus rivularis is one of the more common woody species of mesic, valley bottom intermontane habitats. The species flowers early. Crataegus rivularis is superficially similar to the more or less sympatric, less common, C. saligna; it has larger leaves with fewer veins, larger flowers with ten stamens, and larger pomes. It differs from C. erythropoda little other than in leaf shape and ripe fruit color. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Crataegus ursopedensis is restricted to and locally common in the Bear's Paw Mountains (Montana) and the Cypress Hills (Alberta and Saskatchewan). Crataegus ursopedensis can have strikingly large, deeply incised and sharply lobed, short-shoot leaves; they are often smaller and may then be difficult to differentiate from those of C. rubribracteolata. Compared to the latter, the thorns are often longer, the inflorescences more open, the petioles proportionately longer, the bracteoles paler and, significantly, the pyrene sides more nearly plane. Crataegus ursopedensis is strikingly distinct within ser. Rotundifoliae and perhaps does not belong there. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 9, p. 510. | FNA vol. 9, p. 596. |
Parent taxa | Rosaceae > subfam. Amygdaloideae > tribe Maleae > Crataegus > sect. Douglasia > ser. Cerrones | Rosaceae > subfam. Amygdaloideae > tribe Maleae > Crataegus > sect. Coccineae > ser. Rotundifoliae |
Sibling taxa | ||
Name authority | Nuttall: in J. Torrey and A. Gray, Fl. N. Amer. 1: 464. (1840) | J. B. Phipps & O’Kennon: J. Bot. Res. Inst. Texas 1: 1081, plates 6.1d, 7.4d, fig. 27. (2007) |
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