Quercus huicholensis R.A.McCauley

Tree to 13 m tall and 4 cm dbh, or a shrub, sometimes only 1 m tall. Bark smooth when young, becoming dark grey-black, deeply fissured and corky, young shoots stout, with a tawny tomentum. Leaves evergreen, leathery, obovate to nearly rounded, to 17 × 15 cm, often less, convex, bluntly pointed to rounded at the apex or with a triangular, bristle-tipped tooth, heart-shaped at the base, sometimes deeply, margin nearly entire or with triangular, bristle-tipped teeth, mainly above the centre of the blade. They are glossy dark green above when mature and nearly glabrous except for some tomentum on the midrib and in the vein axils. The lower leaf surface has a dense, pale tan tomentum when young, soon becoming pale grey. Veins 7–10 on each side of the midrib, impressed above and prominently raised beneath. Infructescence to 4 or nearly 6 cm long with up to 8 or sometimes 12 acorns, mostly clustered towards the end. Cupules 4–5 × 7–9 mm, acorns ovoid, 7–11 × 6–8 mm, ⅓ to ½ enclosed in the cup and ripening the first year. (McCauley & Oyama 2020).

Distribution  Mexico Durango, Jalisco, Nayarit, Zacatecas

Habitat Thin soils on rocky slopes and the sides of canyons, growing with a variety of pines and other oaks as well as species of Arbutus and Arctostaphylos; 1650–2820 m.

USDA Hardiness Zone 8

RHS Hardiness Rating H4

Conservation status Not evaluated (NE)

Taxonomic note Plants now referred to this recently named species were previously determined as Quercus conzattii, a species restricted to Oaxaca and Puebla. It differs from that species in having a pale grey rather than brownish tomentum on the leaf underside and the shorter infructescences. It is one of a group of Mexican species with fruits in racemes and with strongly convex leaves included in Subsection Racemiflorae.