Bajo Giuliani (Neogene of Argentina)

Where: La Pampa, Argentina (36.7° S, 64.3° W: paleocoordinates 36.9° S, 62.0° W)

• coordinate estimated from map

• local area-level geographic resolution

When: Huayquerian mammal zone, Cerro Azul Formation, Huayquerian (8.0 - 5.0 Ma)

• Schmidt et al. 2018: Figure 2 illustrates the stratigraphic distribution of the locality giving a general age estimate of 6.0-6.6Ma

•Romano et al. 2023: Biochronological methods were useful in ordering and estimating the age of the different faunas of the Cerro Azul Formation, ranging from ca. 8 to ca. 5.7 Ma. Some appear to be transitional between Chasicoan and “Huayquerian” faunas (Cerro La Bota, Cerro Patagua, and Algarrobo del Águila), and other three (Barrancas Coloradas, El Guanaco, and Caleufú) cover the latest Miocene, even some of them could have reached the earliest Pliocene. The Cerro Azul Formation localities cover the range between ca. 8 to ca. 5.7 Ma (late Tortonian–Messinian; Late Miocene; Fig. 3; Supplementary Online Information 1, Tab. S8). 7.071 Ma (6.811 - 7.541 Ma) for Bajo Giuliani.

• formation-level stratigraphic resolution

Environment/lithology: loess; paleosol/pedogenic, concretionary, nodular, sandy siltstone

• Schmidt et al. 2018: Deposits at Telen, Bajo Giuliani, El Guanaco and Caleufú were interpreted as loess-like deposits with immature palaeosols and little diagenetic alteration (Montalvo et al., 2008, 2016; Verzi et al., 2008).
• Sostillo et al 2018: The Cerro Azul Formation deposits (Linares et al., 1980) are discontinuous along the whole occupied area in the provinces of La Pampa and Buenos Aires (Fig. 2). They are composed of silts, sandy silts and very thin silty sands, reddish and brown colored, with a homogeneous and com- pact general aspect, and frequent carbonate nodules and evidences of pedogenic processes (Folguera and Zárate, 2009). Visconti et al. (2010) interpreted them as eolian de- posits characterized by loessic materials, with a high per- centage of lithic fragments and volcaniclastic sediments. Detailed geological and stratigraphic descriptions of the Cerro Azul Formation are provided by Linares et al. (1980), Goin et al. (2000), Visconti et al. (2010), and Folguera and Zárate (2009)

•Bajo Giuliani are eolian depositions with paleosols.

Size class: macrofossils

Collection methods: Departamento de Ciencias Naturales, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de La Pampa

•Esteban, et al. 2000: Todos los ejemplares analizados están depositados en

•la Cátedra de Geología Histórica de la Facultad de Ciencias Exactas y Naturales de la Universidad Nacional ele La Pampa, Argentina, cuyo acrónimo es GHUNLPam

Primary reference: C. I. Montalvo and S. Casadio. 1988. Presencia del género Paleoctodon (Rodentia, Octodontidae) en el Huayqueriense (Mioceno tardío) de la Provincia de La Pampa. Ameghiniana 25(2):111-114 [C. Jaramillo/J. Carrillo]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 140925: authorized by Carlos Jaramillo, entered by Juan Carrillo on 19.03.2013, edited by Grace Varnham, Miranta Kouvari, Philip Mannion and Kateryn Pino

Creative Commons license: CC BY (attribution)

Taxonomic list

Aves
 Tinamiformes - Tinamidae
Nothura sp.1 Wagler 1827 tinamou
GHUNLPam 8070/1, distal portion of left femur
Mammalia
 Cingulata -
Aspidocalyptus castroi9 Cabrera 1939 edentate
Eosclerocalyptus sp.9 Ameghino 1919 edentate
Coscinocercus sp.9 Cabrera 1939 edentate
 Cingulata - Dasypodidae
Chasicotatus ameghinoi4 Scillato-Yané 1977 armadillo
  - Mylodontidae
Proscelidodon gracillimus6 Rovereto 1914 edentate
GHUNLPam 2418 and MLP 81-XI-1-1
 Notoungulata - Mesotheriidae
Pseudotypotherium sp.9 Ameghino 1904 notoungulate
 Notoungulata - Hegetotheriidae
Hemihegetotherium achataleptum2 Rovereto 1914 notoungulate
GhUNLPam 2231
Paedotherium sp.3 Burmeister 1888 notoungulate
Paedotherium minor12 Cabrera 1937 notoungulate
GHUNLPam 9749, 4318, multiple specimens
Tremacyllus impressus11 Ameghino 1888 notoungulate
GHUNLPam multiple specimens
 Panameriungulata - Proterotheriidae
Proterotheriidae indet.10 Ameghino 1887 placental
Neobrachytherium sp.10 Soria 2001 placental
Diplasiotherium pampa10 Soria 2001 placental
 Rodentia - Echimyidae
Pampamys emmonsae n. sp.14 Verzi et al. 1995 spiny rat
GHUNLPam 2214 (type)
 Rodentia - Abrocomidae
Protabrocoma antiqua9 Rovereto 1914 chinchilla rat
 Rodentia - Octodontidae
Palaeoctodon aff. simplicidens Rovereto 1914 caviomorph
Phtoramys sp.9 Ameghino 1887 caviomorph
Metacaremys calfucalel8 Piñero et al. 2021 caviomorph
GHUNLPam 2338, 2363, 8547, 27058
 Rodentia -
Chasichimys sp.13 Pascual 1967 caviomorph
GHUNLPam 2217
 Rodentia - Chinchillidae
Lagostomus telenkechanum7 Rasia and Candela 2017 viscacha
GHUNLPam 2220, GHUNLPam 2262, GHUNLPam 3694, GHUNLPam 9582, GHUNLPam 12751, GHUNLPam 14584, GHUNLPam 14586.
Lagostomus pretrichodactyla7 Rovereto 1914 viscacha
GHUNLPam 415, GHUNLPam 657, GHUNLPam 2137, GHUNLPam 2192, GHUNLPam 2213, GHUNLPam 2241, GHUNLPam 5123, GHUNLPam 5452, GHUNLPam 8067, GHUNLPam 8071, GHUNLPam 12944, GHUNLPam 18990.
 Rodentia - Caviidae
Dolicavia sp.9 Ameghino 1916 caviomorph
Palaeocavia sp.9 Ameghino 1889 caviomorph
 Paucituberculata - Caenolestidae
Pliolestes venetus n. sp.5 Goin et al. 2000 marsupial
 Didelphimorphia - Didelphidae
Thylamys pinei n. sp.5 Goin et al. 2000 fat-tailed mouse opossum
Zygolestes tatei n. sp.5 Goin et al. 2000 opossum
Thylatheridium hudsoni5 Goin and Montalvo 1988 opossum
 Polydolopimorphia - Argyrolagidae
"Microtragulus rusconii n. sp." = Argyrolagus rusconii5
"Microtragulus rusconii n. sp." = Argyrolagus rusconii5 Goin et al. 2000 metatherian