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Family :


Division :


Genus of this Family


Monoecious trees. Leaves simple, serrate, entire, rarely lobed. Inflorescence of spikes, male, female or mixed with female flowers in the lower part. Male flowers in pendulous catkins, solitary or in clusters of 2-30 along the rachis, sessile or on pedicels. Perianthcampanulate, 4-8 cleft. Stamens as many as or twice of the perianth segments, pistillode rudimentary or obsolete. Female flowers sessile, solitary or in clusters of 3-7, surrounded by a cupule. Ovary 3-celled, styles 3, ovules 2 in each cell. Involucre in fruits often hardened, cupular or altogether closed, often tuberculate or echinate. Fruit a 1-seeded nut, with 1-7 nuts grouped within a cupule.

Key to the Genus

Serial Key Reference
1a. Male and female flowers on seperate shoots; stamens 6; pistillode and staminode absent; cupules not completely covering the nuts Quercus
1b. Male and female flowers in the same inflorescence of rigid, erect, simple and paniculately branched spikes; stamens 12; pistillode and staminode present; cupule completely covering the nuts 2
2a. Bracts lanceolate, equaling or exceeding male flowers clusters; cupule lobed or without ventral division, scaly enclosing a single flower Lithocarpus
2b. Bracts obtuse or broadly acute, obscure or shorter than male flower clusters; cupule spiny, enclosing a female dichasium Castanopsis