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Description
Large, flaky-barked trees.
Stipule subulate, subpersistent.
Inflorescence cymose.
Flower sepals subequal, imbricate, fused at the base to form a shallow cup free from the ovary.
Stamens 25-30;
Ovary ovoid, without distinct stylopodium;
Seed with distinct arillode.
Notes
The only dipterocarpoid genus not recorded from the present or past of S.E. Asia including Ceylon. An isolated and in many ways primitive taxon, with leaves and twigs superficially resembling Monotes, dehiscent pericarp and cymose inflorescence as in some Vatica, a rudimentary aril-like collar on the funicle resembling that in Stemonoporus, androecium somewhat as in Anisoptera and gynoecium somewhat as in Cotylelobium, though the gynoecium and androecium characters together are unique among those genera which share a valvate fruit calyx. The wood anatomy, notably the diffuse distribution of intercellular canals, supports its affinity with the last four genera.