Crataegus chrysocarpa var. vigintistamina

J. B. Phipps

J. Bot. Res. Inst. Texas 1: 1008. 2007.

Endemic
Treatment appears in FNA Volume 9. Treatment on page 600. Mentioned on page 597, 601.

Shrubs, 20–30 dm. Leaves: blade ovate to rhombic-ovate, base ± cuneate, sinuses: max LII 15–20%, lobe apex acute, veins 3–5 per side, abaxial surface glabrous or lamina sparsely hairy at anthesis, veins hairy, adaxial appressed-scabrous, glabrescent. Inflorescences: branches pubescent. Flowers 15–20 mm diam.; hypanthium hairy; stamens 20, anthers cream or ivory. Pomes red, suborbicular, 8–10 mm diam., glabrous.


Phenology: Flowering May; fruiting Sep–Oct.
Habitat: Open brush
Elevation: 100–400 m

Discussion

Variety vigintistamina is similar to var. chrysocarpa except with 20 stamens; it is frequent in parts of Minnesota, where it has the intermediate indumentum mentioned under var. chrysocarpa and var. faxonii. Crataegus divergens (Peck) Sargent, a prior name, with 10 to 18 stamens according to Sargent, is known from New York; its type (C. H. Peck 70) has ten stamens, preventing the name from being used for the current taxon.

Selected References

None.

Lower Taxa

None.
0.8 cm8 mm <br />0.008 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
ivory +  and cream +
James B. Phipps +
J. B. Phipps +
orangebrown +
thin-exfoliating +  and corrugated +
compound +  and simple +
opposite +  and alternate +
cuneate +
Crataegus sect. Rotundifoliae +
5 cm50 mm <br />0.05 m <br /> (7.5 cm75 mm <br />0.075 m <br />) +
purplish +  and yellow +
ovate +  and rhombic-ovate +
2 cm20 mm <br />0.02 m <br /> (5 cm50 mm <br />0.05 m <br />) +
elliptic +  and linear +
adnate +  and distinct +
crowded +, scattered +  and alternate +
Ont. +, Minn. +  and N.Y. +
not +  and aggregated +
100–400 m +
1.5 cm15 mm <br />0.015 m <br /> (2 cm20 mm <br />0.02 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 />) +
yellowish +  and greenish brown or gray-brown +
appressed-pubescent +
Open brush +
constricted +
0.2 cm2 mm <br />0.002 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
crassinucellate +
stipitate-glandular +
deciduous +
glandular-serrate +  and serrate +
short-stipitate-glandular +
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 +
Flowering May +  and fruiting Sep–Oct. +
adnate +, free +, connate +  and distinct +
dark gray-brown +  and russet +
exfoliating +  and corrugated +
pruinose +
0.8 cm8 mm <br />0.008 m <br /> (1 cm10 mm <br />0.01 m <br />) +
suborbicular +
J. Bot. Res. Inst. Texas +
nonaccrescent +
not arillate +
persistent +
free +  and distinct +
appressed +  and erect +
spreading +  and reflexed +
triangular +
4 cm40 mm <br />0.04 m <br /> (?) +
1-50-flowered +  and few-leaved +
concave +  and plane +
free +  and distinct +
branched +  and simple +
persistent +
distinct +
exsert +  and lateral +
elongate +
glabrous +  and tomentose +
Crataegus columbiana var. chrysocarpa +  and C. rotundifolia var. chrysocarpa +
Crataegus chrysocarpa var. vigintistamina +
Crataegus chrysocarpa +
variety +
5 cm50 mm <br />0.05 m <br /> (7 cm70 mm <br />0.07 m <br />) +
black +  and dark mahogany +
straight +
less slender +  and more or less stout +
3 cm30 mm <br />0.03 m <br /> (6 cm60 mm <br />0.06 m <br />) +
craspedodromous +  and gland-tipped +
inconspicuous +
less erect +  and oblique +
1 +  and several +
straight +
determinate +
3 +  and 5 +