Crataegus purpurella

J. B. Phipps & O’Kennon

J. Bot. Res. Inst. Texas 1: 1066, plates 6.2b, 7.2b, fig. 15. 2007.

Common names: Loch Lomond hawthorn
Endemic
Treatment appears in FNA Volume 9. Treatment on page 634. Mentioned on page 633, 635.

Shrubs or trees, 20–35 dm, dense and twiggy. Stems: twigs: new growth ± red, glabrous, 1-year old ± glossy, medium to deep brown, 2-years old gray; thorns on twigs numerous, straight to slightly curved, 1-year old deep brown, 2-years old nearly black, slender to ± stout, 2–3.5 cm. Leaves: petiole length 30–40% blade, sessile-glandular, glands 1–few, small, adaxial sulcus pubescent; blade broadly rhombic to broadly elliptic or oblong, length/width = 0.7–1, 2.5–4 cm at anthesis, 3.5–4.5 (–5) cm mature, base cuneate, lobes 2 or 3 per side, max LII 15–25%, lobe apex acute, margins serrulate or crenate-serrate, veins 3 or 4 (or 5) per side, barely impressed, apex acute to subacute, abaxial surface glabrous, adaxial appressed-scabrous (young), often glabrescent. Inflorescences 6–15-flowered; branches glabrate to sparsely pilose; bracteoles pale-brown, very narrow, margins glandular. Flowers 13–16 mm diam.; hypanthium glabrous or sparsely pilose; sepals usually pale green, triangular, 3 mm, abaxial surface glabrous, adaxial pubescent; anthers pink; styles 3 or 4. Pomes deep red to red-burgundy younger, deep purple fully ripe, ellipsoid to suborbicular, (9–) 11–12 mm, glabrous; sepals eroded or spreading, 4–4.5 mm, pointed; pyrenes 3 or 4, dorsally shallowly or more deeply grooved, sides longitudinally grooved or very shallowly concave.


Phenology: Flowering late May–early Jun; fruiting Aug–Sep.
Habitat: Thickets, light shade of aspen
Elevation: 800–1100 m

Discussion

Crataegus purpurella is known only from the eastern half of the Cypress Hills; it is common in thickets along north-slope draws. The species is most similar to C. rivulopugnensis, with which it is allopatric. In the open, it is a much denser shrub than C. rivulopugnensis; both have short, slender thorns. Crataegus purpurella also differs from C. rivulopugnensis in its usually smaller, proportionately wider, fewer veined leaves and in the deep purple, rather than red, fruit at maturity.

Selected References

None.

Lower Taxa

None.
... more about "Crataegus purpurella"
pubescent +  and glabrescent +
0.8 cm8 mm <br />0.008 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
James B. Phipps +
J. B. Phipps & O’Kennon +
compound +  and simple +
opposite +  and alternate +
cuneate +
8 cm80 mm <br />0.08 m <br /> (12 cm120 mm <br />0.12 m <br />) +
2.5cm +  and 4cm +
broadly rhombic +  and broadly elliptic or oblong +
3.5 cm35 mm <br />0.035 m <br /> (8 cm80 mm <br />0.08 m <br />) +
glabrate +  and sparsely pilose +
adnate +  and distinct +
crowded +, scattered +  and alternate +
Loch Lomond hawthorn +
not +  and aggregated +
800–1100 m +
1.3 cm13 mm <br />0.013 m <br /> (1.6 cm16 mm <br />0.016 m <br />) +
unisexual +  and bisexual +
not +  and aggregated +
not +  and aggregated +
yellow +  and red or purplish +
0.6 cm6 mm <br />0.006 m <br /> (2 cm20 mm <br />0.02 m <br />) +
stipitate-glandular +
gray +, brown +  and red +
old +  and new +
Thickets, light shade of aspen +
pilose +  and glabrous +
constricted +
0.2 cm2 mm <br />0.002 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
crassinucellate +
deciduous +
craspedodromous +
crenate-serrate +  and serrulate +
glandular-denticulate +
inferior +  and superior +
biseriate +  and clustered +
collateral +  and basal +
0.8 cm8 mm <br />0.008 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
elliptic +  and circular +
0 (?) +  and 4 (?) +
free +  and distinct +
post-mature +
sessile-glandular +  and eglandular +
sessile-glandular +
Flowering late May–early Jun +  and fruiting Aug–Sep. +
adnate +, free +, connate +  and distinct +
dark gray-brown +  and russet +
exfoliating +  and corrugated +
0.9 cm9 mm <br />0.009 m <br /> (1.1 cm11 mm <br />0.011 m <br />) +
red +  and red-burgundy +
0.8 cm8 mm <br />0.008 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
ripe +  and younger +
ellipsoid +  and suborbicular +
1.1 cm11 mm <br />0.011 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
J. Bot. Res. Inst. Texas +
not arillate +
persistent +
free +  and distinct +
pointed +  and triangular +
0.4 cm4 mm <br />0.004 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
1-50-flowered +  and few-leaved +
concave +
free +  and distinct +
branched +  and simple +
persistent +
distinct +
exsert +  and lateral +
elongate +
glabrous +  and tomentose +
Crataegus purpurella +
Crataegus (sect. Unassigned) ser. Montaninsulae +
species +
4 cm40 mm <br />0.04 m <br /> (5 cm50 mm <br />0.05 m <br />) +
black +  and brown +
straight +  and slightly curved +
slender +  and more or less stout +
2 cm20 mm <br />0.02 m <br /> (3.5 cm35 mm <br />0.035 m <br />) +
craspedodromous +  and gland-tipped +
inconspicuous +
straight +
scabrous +  and glabrous +
4 +  and 3 +
tree +  and shrub +