La Flora Triásica del Grupo El Tranquilo, Provincia de Santa Cruz (Patagonia). Parte IV. Pteridospermae.

SILVIA GNAEDINGER; RAFAEL HERBST,

AMEGHINIANA

ASOCIACION PALEONTOLOGICA ARGENTINA

Año: 1998 vol. 35 p. 53 - 65

0002-7014

ABSTRACT. THE TRIASSIC FLORA OF THE EL TRANQUILO GROUP, SANTA CRUZ PROVINCE (PATAGONIA). PART IV. PTERIDOSPERMAE. The pteridosperms of the El Tranquilo Group (Upper Triassic of Patagonia) are studied. Well known and widespread Gondwana species are only mentioned while less known taxa are described. The list of species comprises: Dicroidium crassum (Menéndez) Petriella, D. dubium (Feistmante) Gothan, D. lancifolium (Morris) Gothan, D. odontopteroides (Morris) Gothan, D. townrovii Retallack, Dicroidium sp. 1, Dicroidium sp. 2; Diplasiophyllum hughesi (Feistmantel) Frenguelli, Xylopteris argentina (Kurtz) Frenguelli, X. rigida (Dun) Jain y Delevoryas, X. spinifolia (Tenison-Woods) Frenguelli, Zuberia zuberi (Szajnocha) Frenguelli, Lepidopteris madagascariensis (Carpentier) Townrow, L. stormbergensis (Seward) Townrow; Scytophyllum neuburgianum Dobruskina. The taxonomic rank ofvariety in this group ofplants is not accepted as it can be shown that most ofthem are transitional forms within species polymorphism.