Ficus crassiuscula is a species of flowering plant in the family Moraceae, native to Central America (Guatemala, Honduras, Belize, Nicaragua, Costa Rica, Panama) and north-western parts of South America (Colombia, Ecuador, Peru and Venezuela).

[2] In the 1960 Flora of Panama Gordon P. DeWolf Jr. considered this species to be a synonym of the non-climbing F. insipida,[4] but this taxonomic interpretation has not been followed by subsequent authorities.

[7] Among the fig species in subgenus Pharmacosycea, Ficus crassiuscula is quite unique: all the other species are tall, non-climbing, free-growing trees, but F. crassiuscula instead starts its life as an epiphyte (it is a hemiepiphyte), usually germinating near the ground on the lower tree trunk.

As a juvenile it also spreads along the ground, sometimes eventually forming a sprawling thicket - this enables the plant to find its favourite host trees.

Its favoured hosts are Guarea tuisana and Sapium pachystachys, and it is also frequently found on already-dead trees.