Quebrada Honda (Miocene of Bolivia)

Where: Tarija, Bolivia (22.0° S, 65.4° W: paleocoordinates 22.3° S, 62.2° W)

• coordinate stated in text

• local area-level geographic resolution

When: Honda Group, Serravallian (13.8 - 11.6 Ma)

• The formation is apparently unnamed. MacFadden et al., indicate that the locality is constrained by 40K/40Ar ages of 12.83 ± 0.11 Ma and 11.96 ± 0.11 Ma, and that the local magnetostratigraphy is correlated to chrons C5AA through C5A on the MPTS. The extrapolated age for the fossil mammals (based on paleomag) is 13.0 to 12.7 Ma = Laventan SALMA. Although specific statigraphic data were taken for the specimens collected by MacFadden and Wolff, these data were not provided in the publication. MacFadden et al. (1990) indicate that most of the fossil mammals come from a zone "between about 25 to 82 m within our composite measured section."

•(From Brandoni et al., 2018): MacFadden et al. (1990) correlated the two basalmost local paleomagnetic zones of the Quebrada Honda outcrops – from which most fossils derive – to C5AAn and C5Ar.3r of the geomagnetic polarity time scale (GPTS), resulting in an extrapolated age of ca.13.0–12.7 Ma. This corresponds to a slightly older interval (13.2–12.9 Ma) within the Serravallian Age (13.8–11.6 Ma; Gradstein et al. 2012) based on the most recent iteration ofthe GPTS (Ogg 2012).

• group of beds-level stratigraphic resolution

Environment/lithology: fluvial; silty, calcareous claystone and silty, sandy siliciclastic

• (From MacFadden and Wolff, 1981) "The section at Quebrada Honda is divisible into three major parts which appear to represent different environments of deposition. The first, or basal portion (lower quarter of section), consists primarily of extremely fossiliferous reddish-brown silty clays, silts, and sands. The majority of the fossils collected during 1978 cane from this part of the stratigraphic section. Near the edges of the Tertiary valley the silts and clays rest upon a basal breccia conglomerate formed by slope wash from the surrounding hills. This breccia conglomerate does not extend far toward the center of the basin;, where the silts and clays rest on the Paleozoic basement. The middle half of the section consists of slightly fossiliferous silty clays and numerous well-indurated calcareous zones that form prominent ledges and cliffs. The third portion (upper quarter) of the section consists of reddish-brown and yellowish-green clays and clay silts, zones of channel sands, gravels, and conglomerates. Quaternary deposits rest unconformably upon the Tertiary sediments at the top of the section. The uppermost Tertiary sediments yielded only rare bone fragments, and exposures are uncommon and difficult to work. Sixty-two paleomagnetic sites, each consisting of at least 3 separately-oriented hand samples, were collected from the finer-grained sediments in Sections 1 and 2 at Quebrada Honda (Fig. 2; stratigraphic separation between superposed sites averages 4-5 m. These samples are presently being analysed at the University of Florida Paleomagnetic Laboratory. The relatively thick stratigraphic section and closely spaced paleomagnetic sampling provides an excellent potential for establishing the age of the Quebrada Honda sequence by calibration to the Magnetic Polarity Time Scale. At least 8 ashes crop out in the Quebrada Honda sequence. Most of these appear to be sub-aerial deposits. Bulk ash samples (about 50 kg) were collected from Section 1, Unit 9 and Section 2, Unit 17. Preliminary laboratory examination of these samples demonstrates that (particularly Section 2, Unit 17), they have significant quantities of glass and zircons that would be datable by the fission-track method. In addition, hand samples of the other 6 ashes were collected in order to determine which of these are also potentially datable."

•From MacFadden et al., (1990): "These sections consist of about 300 m of principally fine-grained fluviatile sediments with predominant lithologies reddish brown and yellowish-green silty clays, silts, and fine sands. There are also coarser, lenticular challen sands and gravels, but these are localized."

Size classes: macrofossils, mesofossils

Preservation: permineralized

Reposited in the MNHN, MNHN (La Paz)

Collection methods: surface (float), surface (in situ), mechanical,

• Specimens are also curated at Florida Museum of Natural History.

Primary reference: R. Hoffstetter. 1977. Un gisement de mammifères miocènes à Quebrada Honda (sud Bolivien). Comptes Rendus de la Académie des Sciences, Paris, Sèrie D 284:1517-1520 [D. Croft/D. Croft/D. Croft]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 38071: authorized by Darin Croft, entered by Darin Croft on 08.04.2004, edited by Andrés Cardenas, Mark Uhen, Evangelos Vlachos and Patricia Holroyd

Creative Commons license: CC BY (attribution)

Taxonomic list

Phylllophaga indet.
based on presence of larger metacarpal
 Testudines - Pantestudinidae
cf. Chelonoidis sp.1 Fitzinger 1835 turtle
Large size; UATF-V-001867 (scapula-acromion and left epiplastron), UATF-V-00964 (costal bone fragments) and UATF-V- 001778 (right xiphiplastron)
 Testudines - Panchelidae
cf. Acanthochelys sp.1 Gray 1873 sideneck turtle
UATF-V-001850 (left xiphiplastron)
 Notoungulata - Toxodontidae
cf. Paratrigodon sp.2 Cabrera and Kraglievich 1931 notoungulate
MNHN 6542 specimen
 Notoungulata - Hegetotheriidae
Hemihegetotherium trilobus n. sp.3 Croft and Anaya 2006 notoungulate
size of Hemihegetotherium
 Notoungulata - Interatheriidae
Miocochilius federicoi2 Croft 2007 notoungulate
 Notoungulata - Mesotheriidae
Mesotheriinae indet. Alston 1876 notoungulate
based on partial humerus; size of Microtypotherium or smaller Plesiotypotherium
 Rodentia - Chinchillidae
Chinchillidae "sp. 3" Bennett 1833 chinchilid
smallest form, Hoffstetter indicates it should be a new genus (only two lobes on M3, and discontinuous enamel)
Prolagostomus sp.4 Ameghino 1887 chinchilid
Lagostominae "sp. 1" Wiegmann 1832 chinchilid
largest form
Lagostominae "sp. 2" Wiegmann 1832 chinchilid
intermediate form
 Rodentia -
Guiomys unica4 Pérez 2010 caviomorph
specimens UATF-V-000962 and UATF-V-001038
 Rodentia - Dasyproctidae
Mesoprocta hypsodus4 Croft et al. 2011 caviomorph
 Rodentia - Caviidae
Caviidae indet.9 Waterhouse 1839 caviomorph
 Rodentia - Octodontidae
Octodontidae indet. Waterhouse 1839 caviomorph
reported by Villarroel
 Rodentia - Echimyidae
Echimyidae indet. Gray 1825 spiny rat
reported by Villarroel
Quebradahondomys potosiensis4 Croft et al. 2011 spiny rat
holotype and specimen UF 26714
 Rodentia -
Acarechimys sp.4 Patterson 1965 caviomorph
specimens UATF-V-000896, UATF-V-000897, UATF-V-000934, UATF-V-000935, UATF-V-000940, UATF-V-000950, UATF-V-000952, UATF-V-000958, UATF-V-000960, AMNH 107907 (= UF 26695), AMNH 107908 (= UF 26696), AMNH 107909 (= UF 26697), AMNH 107910 (= UF 26698 or 26699), AMNH 107912 (= UF 26698 or 26699), AMNH 107911 (= UF 26713)
 Rodentia - Capromyidae
Capromyidae indet.9 Smith 1842 hutia
 Astrapotheria - Astrapotheriidae
? Xenastrapotherium indet.7 Kraglievich 1928 placental
Uruguaytherium-Xenastrapotherium group
 Xenarthra - Dasypodidae
Euphractinae indet. Winge 1923 armadillo
larger euphractine, along Paraeuphractus-Euphractus lineage
cf. Prozaedyus sp. Ameghino 1891 armadillo
smaller euphractine
 Xenarthra - Megatheriidae
Hapalops angustipalatus8 Ameghino 1891 edentate
Hapalops-Pelecyodon group
 Xenarthra -
Hiskatherium saintandrei n. gen. n. sp.10
Hiskatherium saintandrei n. gen. n. sp.10 Pujos et al. 2011 edentate
 Xenarthra - Glyptodontidae
Propalaehoplophorus andinus8 glyptodon
listed as "Scérocalyptiné"
 Litopterna - Macraucheniidae
Macraucheniidae indet. Ameghino 1889 eutherian
 Litopterna - Proterotheriidae
Proterotheriidae indet. Ameghino 1887 eutherian
size of Proterotherium australe
 Sparassodonta -
Australogale leptognathus n. gen. n. sp.5 Engelman et al. 2018 metatherian
from Rio Rosario area, loc. B-07-22
Acyon myctoderos6 Forasiepi et al. 2006 metatherian
 Sparassodonta - Borhyaenidae
Borhyaenidae indet.9 Savage 1951 metatherian
 Paucituberculata - Caenolestidae
Caenolestidae indet.9 Trouessart 1898 marsupial