THE TRIASSIC PALEOFLORA OF CERRO CACHEUTA, MENDOZA PROVINCE, ARGENTINA. PETRIELLALES, CYCADALES, GINKGOALES, VOLTZIALES, CONIFERALES, GNETALES INCERTAE SEDIS GYMNOSPERMS. Four stratigraphic logs were measured in detail at the Cacheuta hill (northwestern Mendoza Province, Argentina), and seven plantiferous levels were determined at Puesto Míguez and Agua de las Avispas. The main purpose of this paper is the systematic study of the paleoflora found in these secctions; the analized taxa belong to the Gymnospermopsida: Petriellales, Cycadales, Ginkgoales, Voltziales, Coniferales, Gnetales and Gymnospermophyta incertae sedis. The systematic study includes the following 25 identified taxa: Rochipteris truncata (Frenguelli) comb. nov., Nilssonia taeniopteroides Halle, Kurtziana brandmayri Frenguelli, K. cacheutensis (Kurtz) Frenguelli, Pseudoctenis falconeriana (Morris) Bonetti, P. spectabilis Harris, Baiera cuyana Frenguelli, B. rollerii Frenguelli, Ginkgoidium bifidum Frenguelli, Sphenobaiera argentinae (Kurtz) Frenguelli, Heidiphyllum elongatum (Morris) Retallack, Telemachus elongatus Anderson, T. lignosus Retallack, Rissikia media (Tenison-Woods) Townrow, Cordaicarpus sp., Gontriglossa sp., Yabeiella brackebuschiana (Kurtz) Ôishi, Y. mareyesiaca (Geinitz) Ôishi, Y. spathulata Ôishi, Y. wielandi Ôishi, Fraxinopsis andium (Frenguelli) Anderson y Anderson, F. major Wieland, F. minor Wieland, Linguifolium lilleanum Arber, L. steinmannii (Solms-Laubach) Frenguelli.