New data on the stem and leaf anatomy of two conifers from the Lower Cretaceous of the Araripe Basin, northeastern Brazil, and their taxonomic and paleoecological implications

Abstract

Pseudofrenelopsis and Brachyphyllum are two conifers that were part of the Lower Cretaceous (Aptian) taphoflora of the Crato Formation, Araripe Basin, northeastern Brazil. The former genus includes, so far, P. capillata and indeterminate species, whilst the latter is mainly represented by B. obesum, the most common plant megafossil recovered from that stratigraphic unit. Here, the stem and leaf anatomy of Pseudofrenelopsis sp. and B. obesum specimens is revisited, including the first report of some epidermal and vascular traits for both taxa from the Crato Formation. Along with its paleoecological significance, the new data suggest the presence of more than one Pseudofrenelopsis species in the Aptian taphoflora of the Araripe Basin and further support the taxonomic placement of B. obesum within Araucariaceae.

Some Conifers from The Early Cretaceous (Late Aptian – Early Albian) of Catefica, Lusitanian Basin, Western Portugal

“…that have been reported from the Berriasian -Albian in Brazil, the Czech Republic, China, Columbia, England, Mexico, Korea, Poland, Portugal, Spain, Sudan and USA (e.g. Nathorst 1893, Reymanόwna and Watson 1976, Watson and Alvin 1976, Alvin 1977, Watson 1977, Alvin et al 1981, Zhou 1983, Hluštík 1988, Srinivasan 1995, Saiki 1999, Deng et al 2005, Axsmith 2006, Moreno Sánchez et al 2007, Yang and Deng 2007, Mendes et al 2010, Sun et al 2011, Kim et al 2012, Hill et al 2012, Villanueva-Amadoz et al 2014, Sucerquia et al 2015, Peixoto Batista et al 2017).…”

Araucarian conifer from late Albian amber of northern Spain

“…; Batista et al . ), and accommodates twigs possessing few characters, particularly if only impressions of twigs are available. Our specimens are important for their association with araucariacean male cones, whereas a specimen described by Batista et al .…”

“…Our specimens are important for their association with araucariacean male cones, whereas a specimen described by Batista et al . () from the Early Cretaceous of Brazil preserves the anatomy of its wood, in addition to the epidermal characters. Several species described from the mid‐Cretaceous of Europe and North America are similar to B. obesum .…”

New plant fossils from the Lower Cretaceous of the Parnaíba Basin, Northeastern Brazil: Southern Laurasia links

“…obesum is an important component of the paleotropical floras, including those from Northeastern Brazil, where is registered in all known lower Cretaceous deposits This is the case of the sedimentary successions from Japoatã and Riachuelo formations, in Sergipe-Alagoas Basin, Marizal Formation in the Tucano Basin, and Romualdo, Missao Velha, and Santana formations, from Araripe Basin (Teixeira 1948, Duarte 1985, Dutra et al 2002, Kunzmann et al 2004, Sucerquia 2006, Lima et al 2012, Batista et al 2017.…”

“…However, B. obesum from the Santana Formation was assigned to the Araucariaceae based on its cuticle micromorphology and wood features (Kunzmann et al 2004, Sucerquia 2013, Batista et al 2017. The absence of those anatomical features in the preserved form of the Codó Formation, and the associated occurrence of both Classopollis and Araucariacites pollen grains in the Codó Formation (Lima 1982), make difficult to confirm its insertion into the Cheirolepidiaceae.…”