Abstract

Nuevos registros paleobotánicos de la Formación Nestares (Jurásico Temprano), extremo austral de la Cuenca Neuquina, Argentina. Rev. Mus. Argent. Cienc. Nat. [online]. 2017, vol.19, n.2, pp.101-112. ISSN 1853-0400.

Specimens of Rochipteris copiapensis (Solms-Laubach) Herbst, Troncoso & Gnaedinger and of Dejerseya lobata (Jones & de Jersey) Herbst are described for the first time from the Nestares Formation (Early Jurassic), southern extreme of the Neuquén Basin, Argentina. The genus Rochipteris was restricted up to now to Triassic, and the species R. copiapensis (Solms-Laubach) Herbst, Troncoso & Gnaedinger to Norian strata of Argentina and Chile, thus this record constitutes the first reference of the genus for Early Jurassic sequences of Gondwana. A new combination Rochipteris truncata (McLoughlin, Tosolini & Drinnan) nov. comb. is proposed to replace Ginkgophytopsis truncata McLoughlin, Tosolini & Drinnan leaving under synonymy Rochipteris truncata (Frengüelli) Morel, Artabe, Ganuza & Spalletti by priority for which a formal nomenclatural revision is given. The genus Dejerseya has exclusively gondwanic record restricted to Upper Triassic - Lower Jurassic being this, the second record of the genus in Early Jurassic strata of Gondwana. Associated species composing this paleoflora are: Neocalamites carrerei (Zeiller) Halle, Cladophlebis oblonga Halle, C. mendozaensis (Geinitz) Frengüelli, Archangelskya protoloxsoma (Kurtz) Herbst, Otozamites albosaxatilis Herbst, O. ameghinoi Kurtz, O. bechei Brongniart, O. hislopii (Oldham) Feistmantel, Ptilophyllum acutifolium Morris, Alicurana artabei Herbst & Gnaedinger, A. nestarensis Herbst & Gnaedinger, Nilssonia taeniopteroides Halle and Elatocladus planus (Feistmantel) Seward. The age of the Nestares Formation is assign to the late Toarcian on the basis of its palynological content previously described.

Keywords : Paleobotany; Nestares Formation; Early Jurassic; Neuquén Basin; Argentina.