3. Lithocarpus Blume, Bijdr. Fl. Ned. Ind. 10: 526. 1826.
[Greek lithos, stone, and carpos, fruit, referring to the hard fruit wall]
Trees or shrubs , evergreen. Terminal buds present, ovate, all scales imbricate. Leaves: stipules prominent on new growth, persistent around buds. Leaf blade leathery, margins entire or obscurely toothed to serrate, secondary veins unbranched, ± parallel, extending to margin. Inflorescences staminate and androgynous, axillary, often appearing terminal and branched by reduction of leaves, spicate, erect or ascending, rigid or flexible; androgynous inflorescences with pistillate cupules/flowers toward base and staminate flowers distally. Staminate flowers: sepals distinct; stamens 12(-18 or more) typically surrounding indurated pistillode covered with silky hairs. Pistillate flower 1 per cupule; sepals distinct; carpels and styles 3. Fruits: maturation in 2d year following pollination; cupule cup-shaped, without any indication of valves, covering proximal portion of nut, scaly, spines absent, scales strongly reflexed, hooked at tip; nut 1 per cupule, round in cross section, not winged. x = 12.
Species 100-200 (1 in the flora): North America, e Asia.
Although fruit of Lithocarpus closely resembles that of Quercus , the two genera differ in characters of the inflorescence, flowers, and pollen. These characters indicate that Lithocarpus is more closely related to Castanea , Chrysolepis , and other Asian genera of subfamily Castaneoideae than to Quercus , and the similarity in fruit is because of convergence.
