Contribution of nontrees to species richness of a tropical rain forest

We report the results of the first complete samples of all plant species and individuals for any lowland tropical forest in the world. The three forests sampled are in western Ecuador; Rio Palenque, Jauneche, and Capeira are, respectively, wet, moist, and dry forests. In each forest we sampled all vascular plants in a 0.1-ha area. At wet forest Rio Palenque, nontree habit groups make up most of the sampled species and individuals. Over a third of the species and almost half the individual plants are epiphytes, 13 percent of the species are terrestrial herbs, 10 percent are shrubs, and 9 percent nonepiphytic climbers. The moist and dry forest samples have many fewer species, largely due to many fewer epiphytes. The new data are compared with the most diverse 0.1-ha samples from elsewhere in the world. Our wet forest sample is by far the most species-rich such sample yet recorded and would remain so even if all tree species were excluded from the data.