The sequence of siltstones, shales, coquinas and sandstone beds dates to the Devonian period; Late Emsian, Eifelian and Early Givetian epochs, and has a maximum thickness of 600 metres (2,000 ft).

The unit is highly fossiliferous; brachiopods, bryozoans, gastropods, trilobites, corals and bivalves have been found in the Floresta Formation.

dekayi, Dechenella boteroi,[11] Mannopyge sp., Cordania gasepiou, Viaphacops cristata,[12] Anchiopsis armata,[13] Synphoria stemmata, Coronura cf.

grabaui,[15] Belenopyge contusa, Kettneraspis callicera,[16] Placoderm fishes,[17] Platyceras nodosum,[18] Acrospirifer olssoni, Anoplotheca cf.

hamiltonensis, Fenestrellina colombiana, F. olssoni, F. acuta, F. quadrata, F. harrisi, Fistulipora anomala, F. megalopora, Florestacanthus morenoi, Heliophyllum halli,[18] Intrapora fragilis, I. megalopora, Leiorhynchus mysia, Leptaena boyaca, Meganteris australis, Megastrophia hopkinsi, M. pygmaea, Meristella wheeleri, Nucleospira concinna, Odontopleura callicera, Pentagonia gemmisulcata, Phacops cf.

salteri, Pholidops florestae, Platyostoma lineata, Pleurodictyum americanum, Polypora elegantula, P. granulifera, Prismopora inornata, Schellwienella goldringae, Semicoscinium colombiensis, S. minutum, Spinocyrtia cf.

valenteana, Spinulicosta spinulicosta, Spirifer kingi, Strophonella floweri, S. meridionalis, Sulcoretepora olssoni, S. subramosa, Taeniopora florestae, Tropidoleptus carinatus, Unitrypa casteri, Acanthograptus sp., Actinopteria sp, Amphigenia sp., Anthozoa sp., Camarotoechia sp., Cryptonella sp., Cyphaspis sp., Cryphaeus sp., Dalmanites sp., Derbyina sp., Gastropoda sp., Grammysia sp., Homalonotus sp., Leptostrophia sp., Mediospirifer sp., Orthoceras sp., Ostracoda sp., Orthis sp., Paraspirifer sp., Proetus sp., Pterinea sp., Strophodonta sp., Thamnopora sp., and Vitulina sp.