Mid-Late Devonian assemblages of herbaceous lycophytes from northern Argentina and Bolivia: Age assessment with palynomorphs and invertebrates and paleobiogeographic importance

DI PASQUO, M.M.; NOETINGER, S.; ISAACSON, P.; GRADER, G.; STARCK, D.; MOREL, E.; ANDERSON FOLNAGY, H.

JOURNAL OF SOUTH AMERICAN EARTH SCIENCES

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2015 vol. 63 p. 70 - 83

0895-9811

Implications of a new collection of lycophytes of the genera Haplostigma Seward and Paleostigma Kr?auseland Dolianiti from southern Bolivia and northern Argentina are presented. Fragmented herbaceousstems of lycophytes preserved as compressions, impressions and casts come from the Middle and LateDevonian Pescado (Huamampampa), Los Monos and Iquiri formations at Mataral, Yesera, Angosto delPescado and Balapuca. The interbedded shales and siltstones bearing the lycophytes were also examinedfor palynology. They yielded mostly terrestrial palynomorphs with Grandispora pseudoreticulata andother Eifelian to Givetian species and fewer microplanktonic species (i.e., acritarchs, prasinophytes,chitinozoans). At Yesera, diagnostic spores and elements of the microplankton suggest a Givetian-Frasnian up to early Famennian age for the Haplostigma beds. Moreover, presence of the samebrachiopod taxon in the Haplostigma intervals at Yesera Dique (palynologically barren) and Yesera Centrosupports their correlation. This new information supports terrestrial connections between these Bolivianand Argentine areas and other regions of South America in the Eifelian e Givetian AfrosouthamericanSubrealm, which extended up to the early Famennian.