Quercus pinnativenulosa C.H.Mull.

Mexico, endemic to the Sierra Madre Oriental (Hidalgo, Nuevo Leon, Oaxaca, Querétaro, San Luis Potosi, Tamaulipas and Veracruz); 800-1900 m;

7-20 m tall, trunk to 0.5 m in diameter;

6-13 x 1.8-3 cm; more or less leathery; lanceolate to elliptic-lanceolate; apex acuminate with long bristle-tip, often in a spiral; base acute, seldom rounded; margin entire, sometimes slightly undulate and even remotely rolled under (old trees); yellowish green, lustrous, hairless above; hairless beneath; somewhat concolor; 8-18 vein pairs, angled more than 45° with the midvein , flat or impressed above but not conspicuously, flat or weakly raised below; epidermis smooth, slightly papillose ; petiole 5-17 mm long, glabrous;

in March-April; male catkins 6-9 cm long, with some unicellular hairs, lax; female inflorescence 5-8 mm long, most often 2 flowered;

acorn 1-1.8 cm long, 1 cm wide; solitary or paired on a 5-8 mm long stalk; nut enclosed 1/3 by cup; cup half-round with straith margin, 0,7-0,9 cm wide, with triangular, pubescent scales; maturing in 2 years from August to October;

mixed cloud mountain forests (with Q.affinis , Q.polymorpha ) ; withstands -16°C;

– A. Camus : n° 353; – Sub-genus Quercus, section Lobatae, Series Erythromexicanae, Group Eugeniaefoliae; – Not well known; area restricted; – Closely related to Q.salicifolia Liebm., from which it differs in having narrower leaves (2-4 cm for salicifolia ) longly acuminate at apex, base cuneate (round for salicifolia ), veins less prominent beneath, petiole longer (1-6 mm for salicifolia ), stipules longer (5 mm for salicifolia ), and acorns maturing in 2 years (annual for salicifolia ); – Q. pinnativenulosa is distinguished from Q. delgadoana by its leaves with a flat, not revolute, margin, shiny adaxially and with secondary veins flat (not impressed); Q. delgadoana has leaves with a revolute margin, dull and glaucous adaxially and the veins are impressed on the adaxial blade surface. See HERE to compare with other whole-leaved oaks .