Paleontology, sedimentology and paleoenvironment of a new fossiliferous locality of the Jurassic Cañadón Asfalto Formation, Chubut Province, Argentina

A new genus of coccolepidid fishes (Actinopterygii, Chondrostei) from the continental Jurassic of Patagonia

“…to this unit based on palynological evidence from the type section of this unit, the same authors later (Cabaleri et al, 2010a;Gallego et al, 2011) returned to the use of the name "Puesto Almada Member of the Cañadón Asfalto Formation" for the "estratos de Almada." The argument for this change was that a Late Jurassic (Tithonian) chronostratigraphic date obtained from the type locality at Puesto Almada (Cabaleri et al, 2010b) was at odds with the assumed Early Cretaceous age of the Cañadón Calcáreo Formation.…”

“…These authors accepted the Callovian-Oxfordian age for the megasequence I (Cañadón Asfalto Formation sensu Stipanicic et al, 1968), but argued for a latest Jurassic to Early Cretaceous age for their megasequence II, citing biostratigraphic evidence from unpublished internal reports of the oil com- Silva Nieto et al (2002) also maintained the "estratos de Almada" in the Cañadón Asfalto Formation, but argued that the lower and upper section of this formation were concordant and both represented a Callovian-Oxfordian age. The two sections were formally denominated as Las Chacritas and Puesto Almada Members, respectively, by Silva Nieto et al (2003), and this scheme was followed by Cabaleri et al ( , 2010aCabaleri et al ( , 2010b, , and Gallego et al (2011). However, these authors noted an increasing discordance in age between the two members, with new bio-and chronostratigraphic evidence indicating a Bajocian-Bathonian age for the Las Chacritas Member (Volkheimer et al, 2008;Cabaleri et al, 2010b) and an Oxfordian-Tithonian age for the Puesto Almada Member (Cabaleri et al, 2010a(Cabaleri et al, , 2010bGallego et al, 2011).…”

“…The two sections were formally denominated as Las Chacritas and Puesto Almada Members, respectively, by Silva Nieto et al (2003), and this scheme was followed by Cabaleri et al ( , 2010aCabaleri et al ( , 2010b, , and Gallego et al (2011). However, these authors noted an increasing discordance in age between the two members, with new bio-and chronostratigraphic evidence indicating a Bajocian-Bathonian age for the Las Chacritas Member (Volkheimer et al, 2008;Cabaleri et al, 2010b) and an Oxfordian-Tithonian age for the Puesto Almada Member (Cabaleri et al, 2010a(Cabaleri et al, , 2010bGallego et al, 2011). Nevertheless, both members were maintained in the Cañadón Asfalto Formation.…”

Mesozoic Coleopteran Faunas from Argentina: Geological Context, Diversity, Taphonomic Observations, and Comparison with Other Fossil Insect Records

“…Later, Feruglio [21] reported the presence of silicified coleopteran remains from the Laguna del Molino locality of Gran Bajo de San Julian, in Santa Cruz Province) associated with plant fragments, bones, freshwater mollusks, and conchostracans. These previous contributions of insect reports were summarized by Gallego and Martins-Neto [49], Martins Neto and Gallego [24,50], Monferran et al [32,51,52], Genise et al [53], and Gallego et al [54] who reported new finds of insects from the orders Coleoptera (elytra and body remains), Heteroptera (fragmentary wings), and Trichoptera (wing fragments and larval cases) from both the La Matilde Formation of the Laguna del Molino locality and Cañadón Asfalto Formation of Cerro Cóndor and Estancia Fossati localities. These records are associated also with gastropods, bivalve mollusks, ostracods, conchostracans, plants, and fish remains.…”

“…The assemblage recorded from the Estancia Fossati locality came from three levels consisting of shales, limestones, and tuffs, associated with invertebrates such as bivalve mollusks, insect larval cases, ostracods, conchostracans), and fish scales. The Estancia Fossati faunas represent low-energy shallow freshwater environments within associated plant communities [54,59].…”