Cecropia palmata Willd.

Tree with infructescences

Infructescences. Note, infructescences at left are eaten by bats

Fruits obovoid to oblong, ca. 2 x 1.3 x 0.7 mm, whitish-yellow, glossy, the basal end roundish, the apical end more or less flat, obtuse, the transverse section triangular-rounded, or elliptic, the surface tuberculate, the tubercles small; mucilage layer ca. 0.06 mm thick exudes after placed of fruits in water. Pedicel scar conspicuous, basal-lateral, elliptic; vascular bundle single, on one lateral side. Pericarp ca. 150 µm thick, thicker on lateral sides, thinner on middle of dorsal and ventral sides, with 6-14 layers, differentiated into exocarp, mesocarp, and endocarp. Exocarp single-layered, with two cell types, the first large, mucilaginous, with thin anticlinal walls and thickened outer periclinal walls, considerably elongated without destruction of cell boundaries when wet, the second cell type non-mucilaginous, much smaller, with thicker walls, filled with light brown pigment, the non-mucilaginous cells are rare and situated at apex of tubercles. Mesocarp 4-12 layers thick, differentiated into three zones, the outer zone of single layer of small cells with thickened, non-lignified walls, the intermediate zone of 2-10 (more layers on lateral sides) longitudinaly elongated macrosclereids with layered thickened walls, the inner zone a single layer of cells, each with a prismatic crystal 6.5-9 µm diam. Endocarp occupying one-half to two-thirds of pericarp, a single layer of radially elongated macrosclereids, longer under tubercles, with very narrow lumens, the lumens broad and more-or-less roundish at apex, the cell walls considerably thickened, with thin tiny pores, the pores thicker at cell apex. Seeds obovoid, 1.6 x 1.2 x 0.5 mm, light yellow, 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 reduced to membrane 8-9 µm thick, of two cell layers, the cells of first layer longitudinally elongated, very small, flat, thin-walled, the larger cells of second layer transversally elongated, thicker walled, filled with tannins. Endosperm of 2-6 layers, the cells thin-walled, with protein bodies, starch grains, and oil. Embryo linear, straight, ca. 1.1 x 0.6 mm, the cotyledons large (ca. 0.7 mm long), plano-convex.

Bat dispersers. Artibeus jamaicensis, A. lituratus, A. obscurus, Carollia perspicillata, Platyrrhinus helleri, Uroderma bilobatum, U. magnirostrum.

Voucher specimens. Berg 784 (herbarium specimen), Charles-Dominique s. n. (fruits from bat feces)

For more information regarding fruit morphology and dispersal ecology of Cecropia species in French Guiana see Lobova et al., 2003.