Cecropia obtusa Tréc.

Fruits lanceolate-ellipsoid, ca. 2.9 x 0.8 x 0.8 mm, brown, glossy, the end(s) more or less acute, the transverse section triangular-rounded or elliptic, the surface indistinctly undulate-rugose; mucilage layer ca. 0.1 mm thick exudes after placed of fruits in water. Pedicel scar conspicuous, basal, circular; vascular bundle single, on one lateral side. Pericarp ca. 160 µm thick, thicker on lateral sides, thinner in middle of dorsal and ventral sides, with 5-9 layers, differentiated into exocarp, mesocarp, and endocarp. Exocarp single-layered, with two cell types: the first mucilaginous, with wavy, thin, anticlinal walls and thickened outer periclinal walls, considerably elongated when wet, the cell boundaries usually not destroyed upon wetting, the second cell type non-mucilaginous, with thin walls, filled with brown pigment, the mucilaginous cells more abundant and surrounding small groups of non-mucilaginous cells. Mesocarp 3-7 layers thick, differentiated into two (on dorsal and ventral sides) or three (on lateral sides) zones, the outer zone 2-4 layers of longitudinally elongated cells filled with brown tannins, the cell walls slightly thickened, the outer periclinal walls of first layer thicker, the intermediate zone present on lateral sides, of 1-2 layers of sclerified stone cells, the inner zone a single layer of cells, each with a large prismatic crystal 11-18 µm diam. Endocarp occupying one-half to two-thirds of pericarp, consisting of a single layer of radially elongated macrosclereids with very narrow lumens, the lumens broad and more-or-less roundish at apex as seen in transverse section, the cell walls considerably thickened, with thin tiny pores, the pores thicker at cell apex. Seeds oblong-ovoid, 1.6 x 0.5 x 0.5 mm, light brown, glossy, the micropilar end acute, the transverse section triangular-rounded or elliptic, the surface indistinctly striate-reticulate. Hilum conspicuous, basal, slightly displaced to one side. Seed coat derived from 2 integuments, in mature seed reduced to membrane 8-9 µm thick, of two cell layers, the cells of first layer longitudinally elongated, very small, flat, light brown, thin-walled, the cells of second layer transversally elongated, bigger, thick-walled, filled with tannins. Endosperm of 2-5 layers, the cells thin-walled, with protein bodies, small starch grains, and oil. Embryo linear, straight, ca. 1.5 x 0.4 mm, the cotyledons large (ca. 1 mm long), plano-convex.