Main differences between Q. xylina, Q. obtusata, Q. praeco, Q. rugosa, Q. laeta and Q. deserticola

Q. xylina
Q. obtusata

Q. praeco

Q. rugosa
Q. laeta
Q. deserticola
Blade

6-8 x 3-5 cm, coriaceous, flat, apex round and mucronate sometimes acute, base round or cordate

6-16 x 4-8 cm, flat or sometimes slightly convexe, subcoriaceous, apex round , base rounded to cordate,

4-10 x 2-6 cm
subcoriaceous, apex rounded sometimes subacute, base round or subcordate

4-16 x 3-10 cm, apex round sometimes acute, mucronate, base round or subcordate 5-10 x 2-5 cm, coriaceous, stiff, apex mucronate, base round or subcordate

4-9 x 1.5-3 cm,
sub
coriaceous, apex acute or obtuse, mucronate, base round sometimes cordate

Petiole 0.7-1.3 cm long, glabrescent 0.5-1.2 cm long, glabrescent 0.3-1 cm long 0.5-1.2 cm long, pinkish, downy 0.2-1 cm long, pubescent 0.2-0.6 cm long, tomentose
Margin thick, slightly revolute, with 3-6 pairs of teeth in apical half never entire, slightly revolute, 3-8 pairs of teeth with a short mucro turned to the abaxial face flat or revolute, almost entire or with more or less long mucronate teeth thick, + or - flat, with 3-10 pairs of teeth in apical 2/3, mucro not turned to the abaxial face sometimes entire, thick, slightly revolute, ondulate or often with 3-6 pairs of teeth in apical 1/3 revolute, sometimes entire, often 2-5 pairs of teeth or lobes with straight mucro
Leaf adaxially glabrous, or with some glandular and stellate trichomes simple and multiradiate trichomes along midrib, then glabrescent often some stellate and fasciculate trichomes glabrous, or with some stellate trichome near base glabrous, or with some stellate trichome near base some sparse, multiradiate trichomes along midrib
Leaf abaxially dense, fluffy, persistent, glandular and fasciculate trichomes some stellate and numerous glandular trichomes, abundant glandula secretions same trichomes as adaxially but very dense yellowish or light brown, with stellate and glandular trichomes long pediculate stellate trichomes, sometimes glandular ones, without secretions dense stellate trichomes and some glandular ones
Veins 7-12 pairs, impressed above, raised underneath 7-12 pairs, curved, slightly impressed above 7-12 pairs, flat above or remotely impressed 7-12 pairs, straight or curved 6-11 pairs 6-9 pairs, impressed above, raised beneath
Epidermis papillose, whitish papillose, whitish or pale green, slightly bullate papillose, pale green glaucous, waxy, bullate and papillose papillose, pale glaucous slightly bullate
Acorn 1.5-2 cm long, 1 to 8 together on a 4-10 cm long peduncle 1-1.6 cm, mostly globose, 1 to 5 together on a thin 2-3 cm long peduncle 1.7-2 cm long, ovoid, peduncle 3-7 cm long 2 cm long, acute, 1 to 8 together on a 2-7 cm long peduncle 1 cm long, on a short peduncle or sessile 1.5 cm long, ovoid, on a stout tomentose peduncle 0.3-1 cm long
Cupule straight margin, enclosing 1/2 nut halfround, straight margin margin strongly rolled inside pubescent, verrucose scales pubescent scales thickened at base straight margin, halfround, pubescent scales