Family: Lecythidaceae

Classification: The classification of the species of Eschweilera is still poorly understood and will need additional monographic work to resolve the problems.

The Brazil Nut family. Cayetano.

Diagnosis: Diagnostic features: fibrous bark; leaves alternate, simple; stipules never conspicuous; stamens fused into a staminal tube or ring, the ring expanded on one side in some species to form a hood-like structure that covers the summit of the ovary; ovary inferior or half inferior; fruits either berry-like or, more frequently woody, circumscissile capsules.

Habit: Trees, understory, canopy, or emergent.

Main axis: Trunks unbuttressed or buttressed. Bark fibrous, can be peeled in long strips.

Leaves: Leaves alternate, very large in species of Grias and most species of Gustavia, medium-sized in remaining genera, spirally arranged and clustered at branch ends in Couroupita, Grias, and some species of Gustavia, distichous and not clustered in remaining genera, the margins usually entire, sometimes serrulate to serrate; venation eucamptodromous, brochidodromous, or eucamptrodromous toward base and brochidodromous toward apex.

Stipules: Stipules absent or minute and caducus.

Inflorescence: Inflorescences terminal, axillary, or cauline, of simple racemes or spikes, paniculate arrangements of racemes or spikes, or fasciculate.

Flowers: Flowers actinomorphic or zygomorphic, inferior or half-inferior (some species of Eschweilera), perfect; calyx entire or of 2 to 6 triangular to broadly ovate lobes; petals 4, 6, 8, rarely 12 or 18; stamens arising from a symmetrical staminal tube in Allantoma, some species of Cariniana (e.g., C. decandra), Grias, and Gustavia, the tube slightly expanded on one side in some species of Cariniana, the stamens arising from a staminal ring in remaining species, the ring markedly expanded into a strap-like ligule with an expanded hood in remaining genera, the hood appendages with or without anthers, the pollen fertile in all anthers, or with some anthers with fertile pollen and others with sterile (fodder) pollen; ovary usually 2, 4, or 6-locular, the placenta either axile, then inserted at apex, base, or throughout length of locule, or inserted on floor of locule (Eschweilera).

Fruit: Fruits indehiscent, then somewhat fleshy and berry-like (Grias and Gustavia) or with thin, woody pericarp (Couroupita), or dehiscent via circumscissile operculum, then woody.

Seeds: Seeds with unilateral wing in Cariniana or circumferential wing in Couratari, not winged in remaining genera; funicle well-developed, yellow and contorted in Gustavia augusta and related species, straight and whitish in remaining species; aril absent or present, when present lateral or basal; sarcotesta present in some species of Eschweilera; cotyledons leaf-like in Cariniana, Couratari, and Couroupita, thick and plano-convex in Gustavia, or absent in remaining genera.

Uses: This family is well known for the Brazil nut of commerce.

Distribution: 205 described species in Oaxaca and Veracruz Mexico, Jamaica, Trinidad and Tobago, Belize, Guatemala, Honduras, Nicaragua, Costa Rica, Panama, Colombia, Venezuela, Guyana, Surinam, French Guiana, Ecuador, Perú, Bolivia, Brasil, and Paraguay.

Ecology: Species of this family are most common in non-flooded, lowland, terra firme forests. Some species do occur in periodically inundated habitats and in cloud forests.