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.
James B. Phipps +
J. B. Phipps +
Crataegus sect. Rotundifoliae +
Ont. +, Minn. +  and N.Y. +
100–400 m +
Open brush +
Flowering May +  and fruiting Sep–Oct. +
J. Bot. Res. Inst. Texas +
Crataegus columbiana var. chrysocarpa +  and C. rotundifolia var. chrysocarpa +
Crataegus chrysocarpa var. vigintistamina +
Crataegus chrysocarpa +
variety +