Tithonian (Internispinosum Zone) ammonites from Cordón de Cuchillo Cura, Neuquén Basin, Argentina

A small collection of ammonites from the outcrops of the Los Catutos Member (Vaca Muerta Formation) in Cuchillo Curá indicates a stratigraphic position in the upper Internispinosum Zone. This ammonite assemblage is composed of Cieneguiticeras aff. falculatum (Steuer), Lingulaticeras sp. A, Haploceratoidea indet. (Lamellaptychus), Choicensisphinctes sp. A, Zapalia triplex (Zeiss & Leanza), Catutosphinctes cf. inflatus (Leanza), Catutosphinctes sp. A, Parodontoceras cf. calistoides (Behrendsen), Aspidoceras euomphalum (Steuer), Toulisphinctes cf. rafaeli (Oppel), and Windhauseniceras internispinsoum (Krantz). The record of C. aff. falculatum in the studied outcrop extends the stratigraphic range of the genus, which thus spans from the lowermost Tithonian Picunleufuense Zone up to the upper Internispinosum Zone. P. cf. calistoides is the oldest known record for the genus Parodontoceras.