Monte León (Miocene of Argentina)

Where: Santa Cruz, Argentina (50.3° S, 68.9° W: paleocoordinates 50.9° S, 63.2° W)

• coordinate stated in text

• local area-level geographic resolution

When: Santa Cruz Formation, Santacrucian (17.5 - 16.3 Ma)

• formation-level stratigraphic resolution

Environment/lithology: terrestrial; lithology not reported

Size class: mesofossils

Collected by C. Ameghino, Barnum Brown; reposited in the AMNH, MACN, MLP

Primary reference: S. F. Vizcaíno, R. F. Kay, and M. S. Bargo. 2012. Background for a paleoecological study of the Santa Cruz Formation (late Early Miocene) on the Atlantic Coast of Patagonia. In S. F. Vizcaí­no, R. F. Kay, M. S. Bargo (eds.), Early Miocene Paleobiology in Patagonia: High-Latitude Paleocommunities of the Santa Cruz Formation 1-22 [J. Zijlstra/J. Zijlstra/J. Zijlstra]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 176563: authorized by Jelle Zijlstra, entered by Jelle Zijlstra on 17.02.2016, edited by Miranta Kouvari and Grace Varnham

Creative Commons license: CC BY (attribution)

Taxonomic list

Aves
 Rheiformes - Rheidae
Opisthodactylus patagonicus4 Ameghino 1891 rhea
MNHN 1900-18-1, distal end of left tarsometatarsus
 Gruiformes - Phorusrhacidae
Phorusrhacos longissimus4 Ameghino 1887 terror bird
MNHN 1900-18-3, distal end of a large right tarsometatarsus
Psilopterus sp.4 Moreno and Mercerat 1891 terror bird
MNHN 1900-18-2, phalanx
Reptilia
 Squamata -
Dibolosodon typicus n. gen. n. sp.7, Diasemosaurus occidentalis n. gen. n. sp.7
Dibolosodon typicus n. gen. n. sp.7 Ameghino 1893 tegu
MACN-A 621
Diasemosaurus occidentalis n. gen. n. sp.7 Ameghino 1893 tegu
MACN-A 5806a-b
Mammalia
 Rodentia -
Spaniomys sp.5 Ameghino 1877 caviomorph
MLP 55-XII-13–146 and MLP 84-III-1–36
 Rodentia - Acaremyidae
Acaremys murinus2 Ameghino 1887 caviomorph
MACN PV SC2339, SC2347, SC2410
 Primates - Homunculidae
Homunculus patagonicus9 Ameghino 1891 monkey
MLP 55-XII-13-156, m1 (m2 according to ref. 47173)
 Megatherioidea - Megalonychidae
Eucholoeops fronto6 Ameghino 1891 edentate
MLP 4-2 (first identified by Lydekker as Eucholoeops ingens)
 Cingulata - Chlamyphoridae
Stenotatus sp.12 Ameghino 1891 edentate
MLP 55-III-3-10, skull and mandible
 Paucituberculata - Palaeothentidae
Palaeothentes minutus1 Ameghino 1887 marsupial
Palaeothentes intermedius1 Ameghino 1887 marsupial
Palaeothentes pascuali3 Bown and Fleagle 1993 marsupial
MACN SC numbers 2939, 2945
Palaeothentes lemoinei1 Ameghino 1887 marsupial
Palaeothentes aratae1 Moreno 1882 marsupial
"Acdestis owenii" = Acdestis oweni1 Ameghino 1887 marsupial
Acdestis lemairei1 Bown and Fleagle 1993 marsupial
 Sparassodonta - Borhyaenidae
Arctodictis munizi n. gen. n. sp.8 Mercerat 1891 metatherian
MLP 11-85, holotype, left dentary with p1-m4 and right with p3
Borhyaena tuberata11 Ameghino 1887 metatherian
 Sparassodonta -
"Sipalocyon gracilis" = Sipalocyon gracilis10, "Thylacodictis exilis n. sp." = Sipalocyon gracilis10, "Pseudonotictis pusillus" = Pseudonotictis pusillus11, "Hathliacynus kobyi n. sp." = Pseudonotictis pusillus10, Acyon tricuspidatus n. gen. n. sp.10, "Cladosictis dissimilis n. sp." = Cladosictis patagonica10, "Hathliacynus fischeri n. sp." = Cladosictis patagonica10, "Agustylus primaevus n. sp." = Cladosictis patagonica10
"Sipalocyon gracilis" = Sipalocyon gracilis10 Ameghino 1887 metatherian
MLP 11-22, dentary p3-m2; MLP 11-39, mandible left m1, right m1
"Thylacodictis exilis n. sp." = Sipalocyon gracilis10 Ameghino 1887 metatherian
MLP 11-12, mandible m1-2
"Pseudonotictis pusillus" = Pseudonotictis pusillus11 Ameghino 1891 metatherian
MLP 11-40, dentary m1
"Hathliacynus kobyi n. sp." = Pseudonotictis pusillus10 Ameghino 1891 metatherian
MLP 11-26, jaws, skull fragments, postcrania
Acyon tricuspidatus n. gen. n. sp.10 Ameghino 1887 metatherian
MLP 11-64, dentary p3-m4, holotype
"Cladosictis dissimilis n. sp." = Cladosictis patagonica10 Ameghino 1887 metatherian
MLP 11-86, maxillary M2-4
"Hathliacynus fischeri n. sp." = Cladosictis patagonica10 Ameghino 1887 metatherian
MLP 11-19, partial skull and mandibles
"Agustylus primaevus n. sp." = Cladosictis patagonica10 Ameghino 1887 metatherian
MLP 11-4, mandible c-m1, m3-4