Killik Aike Norte (Miocene of Argentina)

Also known as Estancia Felton, Felton’s Estancia

Where: Santa Cruz, Argentina (51.6° S, 69.5° W: paleocoordinates 52.2° S, 63.7° W)

• coordinate based on nearby landmark

• small collection-level geographic resolution

When: Estancia La Costa Member (Santa Cruz Formation), Santacrucian (17.5 - 16.3 Ma)

• the fossiliferous tuff yielded 40Ar/39Ar ages of 16.45 +/- 0.14, 16.5 +/- 0.2, and 16.5 +/- 0.3 Ma based on "laser incremental-heating analyses of plagioclase"

•Gonzalez and Scilalto-Yané 2008: The Santa Cruz Formation on this site emerges along the canyons of the Gallegos River estuary. Tauber et al. (2004) identified three fossiliferous levels in Killik Aike Norte, so we are not sure of the exact level of provenance of the mentioned findings. It should be noted that the KAN 2 level is the most accessible and rich in fossils; however, a large number of fallen blocks of the upper strata with fossils are also found at this level (Tauber et al., 2005). These authors tentatively correlate the KAN 2 level with the fossil level 6, which emerges in the intertidal zone, in front of Corriguen Aike (Estancia de La Estancia La Costa) and in the southern sector of Cañadón Silva (Tauber, 1994). If this is correct, the origin of the YPM PU 15611, YPM PU 15565 and MPM-PV 1811 materials would not be below the fossiliferous level 6, that is, it would correspond to the higher levels of Protypotherium attenuatum Biozone 1 , in the Estancia La Costa Member (Tauber et al., 2004).

• group of beds-level stratigraphic resolution

Environment/lithology: terrestrial; tuff

• vitric [volcanic] tuff

Size class: macrofossils

Primary reference: M. F. Tejedor, A. A. Tauber, A. L. Rosenberger, C. C. Swisher, III, and M. E. Palacios. 2006. New primate genus from the Miocene of Argentina. Proceedings of the National Academy of Sciences 103:5437-5441 [J. Alroy/J. Alroy]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 87314: authorized by John Alroy, entered by John Alroy on 14.03.2009, edited by Jelle Zijlstra, Miranta Kouvari, Grace Varnham, Philip Mannion and Kateryn Pino

Creative Commons license: CC BY (attribution)

Taxonomic list

Aves
 Gruiformes - Phorusrhacidae
Psilopterus lemoinei4 Moreno and Mercerat 1891 terror bird
MPM-PV3649, anterior part of a skull including the upper bill and jugal bar, and part of the interorbital septum; MPM-PV3650, right humerus, right scapula, right femur, both tibiotarsi, right fibula, and both tarsometatarsi, all from the same individual
Mammalia
 Cingulata - Propalaehoplophoridae
cf. Eucinepeltus sp.8 Ameghino 1891 edentate
MPM PV 17408
 Theriamorpha -
Stegotherium tauberi n. sp.7 Gonzalez and Scilalto-Yané 2008 edentate
nivel KAN 2 (Tauber et al., 2004)
 Megatherioidea - Megatheriidae
Prepotherium filholi n. sp.1 Ameghino 1891 edentate
AMNH 9573, mandible, type
 Megatherioidea - Megalonychidae
Megalonychidae indet.1 Gervais 1855 edentate
AMNH 9249, postcrania
Hapalops sp.1 Ameghino 1887 edentate
AMNH 9252, incomplete postcranial skeleton
 Notoungulata - Interatheriidae
"Interatherium robustum" = Interatherium extensus3 Fernández et al. 2023 notoungulate
AMNH 9284, cranium and mandible; also FMNH P13057 see MacPhee et al. 2021
Interatherium rodens5 Moreno 1882 notoungulate
Protypotherium australe3 Moreno 1882 notoungulate
AMNH 9286, cranium and mandible
Protypotherium praerutilum6 Ameghino 1887 notoungulate
 Notoungulata - Hegetotheriidae
Pachyrukhos moyani3 Ameghino 1885 notoungulate
AMNH 9242, femur, tibia; 9283, cranium, mandible; 9285, ulna, femur; 9481, humerus, ulna
 Notoungulata - Toxodontidae
Nesodon sp.3 Owen 1846 notoungulate
AMNH 9510, mandible
 Panameriungulata - Proterotheriidae
Thoatherium minusculum3 Ameghino 1887 placental
AMNH 9245, cranium
 Primates - Homunculidae
"Homunculus patagonicus" = Homunculus patagonicus9, "Killikaike blakei n. gen. n. sp." = Homunculus patagonicus
"Homunculus patagonicus" = Homunculus patagonicus9 Ameghino 1891 monkey
MPM-PV 3502, cranium, from "base of ash level KAN"; MPM-PV 1607, right M1-3, from "KAN ash level"; probably MACN-A 12498, right dentary with i2-m2, original holotype of _Homunculus patagonicus_ but now lost
"Killikaike blakei n. gen. n. sp." = Homunculus patagonicus Ameghino 1891 monkey
 Microbiotheria - Microbiotheriidae
Microbiotherium acicula12 Ameghino 1891 marsupial
AMNH 9121, dentary p3-m2
Microbiotherium gallegosense n. sp.12 Sinclair 1906 marsupial
AMNH 9591, dentary p3-m2
Microbiotherium tehuelchum12 Ameghino 1887 marsupial
PU 15698, skull
 Paucituberculata - Palaeothentidae
Acdestis oweni2 Ameghino 1887 marsupial
 Paucituberculata - Pichipilidae
Phonocdromus gracilis12 Ameghino 1894 marsupial
AMNH 9123, dentary m1-3; 9593, dentary with teeth
 Sparassodonta - Borhyaenidae
Prothylacynus patagonicus10 Ameghino 1891 metatherian
AMNH 9561, maxilla M2-4; BM(NH) M9178, posterior part of dentary with teeth; PU 15700, partial skull and skeleton
 Sparassodonta -
Sipalocyon gracilis11 Ameghino 1887 metatherian
AMNH 9254, skull and dentary; PU 15373, skull, postcrania