PBDB Collection

Arroyo Chasicó (Miocene of Argentina)

Where: Buenos Aires, Argentina (38.6° S, 63.0° W: paleocoordinates 38.8° S, 60.1° W)

• coordinate estimated from map

• local area-level geographic resolution

When: Arroyo Chasicó Formation, Chasicoan (10.0 - 9.0 Ma)

• A recent interpretation of radiometric and paleomagnetic data of the ACF supports an age between at least 9.43 and 8.7 Ma (Zarate et al., 2007).

• formation-level stratigraphic resolution

Environment/lithology: "floodplain"; sandstone

• The beginning of Chasicoan sedimentation was placed after the general withdrawal of the mid-Miocene transgression (Pascual et al., 1996). According to Ramos (1999b), the transgression extended across most of eastern South America, covering the Pampas, Chaco region, and Patagonia up to the Andean foothill and reaching areas near the central and northern Andes of Argentina. The regional regression that followed was thought to be synchronous with the 10.5 Ma global sea level fall cited by Haq et al. (1987) (see Verzi, 1999, Pascual et al., 1996).

• an extensive plateau capped by a thick calcrete crust, which in turn is covered by a thin apron of late Pleistocene–Holocene eolian deposits.

Size class: macrofossils

Preservation: permineralized

Collection methods: Gonzalez-Ruiz, et al. 2012: their Material was collected during a field trip organized by the Facultad de Ciencias Naturales y Museo de La Plata (Argentina) and Duke University (USA).

•

•Cerdeno 2000: material from the Museo "J. C. Moyana" de Mendoza. Recolección efectuadas por J.R. Contreras, Mones-Aivarado y Ripa-Alvara- do entre 1967 y 1969, según figura en las etiqueta encontradas junto a los fósiles.

Primary reference: M. A. Zárate, P. H. Schultz, A. Blasi, C. Heil, J. King and W. Hames. 2007. Geology and geochronology of type Chasicoan (late Miocene) mammal-bearing deposits of Buenos Aires (Argentina). Journal of South American Earth Sciences 23:81-90 [D. Croft/D. Croft]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 79180: authorized by Darin Croft, entered by Darin Croft on 27.02.2008, edited by Bettina Kaphingst, Juan Carrillo, Jelle Zijlstra, Miranta Kouvari, Grace Varnham, Evangelos Vlachos and Kateryn Pino

Creative Commons license: CC BY (attribution)

Taxonomic list

• Rasia & Canela 2017: Arroyo Chasico area, southwest of Buenos Aires Province, Argentina, MLP-Pv 55-IV- 28-43 and MLP-Pv 55-IV-28-44 come from in front of Rado- vitzki farm; MLP-Pv 55-IV-28-42 comes from in front of Torres and Stefanazzi farms; MLP-Pv 60-VI-18-101 comes from the left margin of Stefanazzi farm; MLP-Pv 76-VI-12-47 comes from the left bank of Arroyo Chasic?o, 400 m upstream from Bajada de los Toros; MLP-Pv 60-VI-18-100, MLP-Pv 60-VI-18-107, MLP-Pv 92-XI-19-1, and MLP-Pv 92-XI-19-2 come from the Arroyo Chasic?o area, without more precise geographic provenance.

Show authors, comments, and common names

Amphibia
Salientia -	Anura indet.¹ Anura indet.¹ frog leg bone
Mammalia
Megatherioidea - Megalonychidae	Protomegalonyx chasicoensis² Protomegalonyx chasicoensis² Scillato-Yané 1977 edentate femur MMP M 478
Megatherioidea - Megatheriidae	Plesiomegatherium halmyronomum n. sp.⁴, Anisodontherium halmyronomum n. gen.³ Plesiomegatherium halmyronomum n. sp.⁴ Cabrera 1928 edentate the type. barranca derecha del arroyo chasico. cerca de la laguna del mismo nombre Anisodontherium halmyronomum n. gen.³ Cabrera 1928 edentate Holotype: MLP 26-IV-10-1
Cingulata - Pampatheriidae	Kraglievichia sp.¹⁵ Kraglievichia sp.¹⁵ Castellanos 1927 edentate two osteoderms. M.L.P.: 55-N-28-84; 60-VI-18-68; CH lla(l). M.M'.P.: 265-M; ' 358-M (ref 27152 also)
Cingulata - Glyptodontidae	Plohophorini "1"¹, Plohophorini "2"¹, "Sclerocalyptini "1"" = Hoplophorini¹, "? Sclerocalyptini "2"" = Hoplophorini¹ Plohophorini "1"¹ Castellanos 1932 glyptodon one osteoderm and two osteoderms from the tail Plohophorini "2"¹ Castellanos 1932 glyptodon one osteoderm from the tail "Sclerocalyptini "1"" = Hoplophorini¹ Huxley 1864 glyptodon one osteoderm "? Sclerocalyptini "2"" = Hoplophorini¹ Huxley 1864 glyptodon one osteoderm
Cingulata -	Palaehoplophorini "1"¹, Palaehoplophorini "2"¹, Palaehoplophorini "3"¹, Palaehoplophorini "4"¹, Palaehoplophorini "5"¹, Palaehoplophorini "6"¹, Palaehoplophorini "7"¹, ? Palaehoplophorini "8"¹, Palaehoplophorini "9"¹ Palaehoplophorini "1"¹ Hoffstetter 1958 edentate four osteoderms Palaehoplophorini "2"¹ Hoffstetter 1958 edentate ten osteoderms Palaehoplophorini "3"¹ Hoffstetter 1958 edentate five osteoderms Palaehoplophorini "4"¹ Hoffstetter 1958 edentate two osteoderms Palaehoplophorini "5"¹ Hoffstetter 1958 edentate one osteoderm Palaehoplophorini "6"¹ Hoffstetter 1958 edentate one osteoderm Palaehoplophorini "7"¹ Hoffstetter 1958 edentate one osteoderm ? Palaehoplophorini "8"¹ Hoffstetter 1958 edentate four osteoderms Palaehoplophorini "9"¹ Hoffstetter 1958 edentate one osteoderm
Cingulata - Dasypodidae	Vetelia perforata n. sp.¹⁵, Peltephilinae indet.¹⁵, Proeuphractus sp.¹⁵, Chasicotatus ameghinoi n. gen. n. sp.¹⁵ Vetelia perforata n. sp.¹⁵ Scillato-Yané 1977 armadillo seven specimens. Holotype: MLP 28-X-11-45 (also ref 27152) Peltephilinae indet.¹⁵ Lydekker 1894 armadillo MLP 28-X-11-88 Proeuphractus sp.¹⁵ Ameghino 1886 armadillo four specimens. M.L.P.: 28-X-1l-62; 28-X-11-67; 55-N-28-81a; 55-N-28-87a; 60-VI-18-77; 60-VI-18-78; CH 19; CH 35a; CH 36. M.M.P.: 264-M; 285-S. Also ref 71054: MCNAM-PV 3226, 7 Chasicotatus ameghinoi n. gen. n. sp.¹⁵ Scillato-Yané 1977 armadillo eight specimens. Holotype: MLP CH 10 (also ref 27152)
Cingulata - Peltephilidae	Epipeltephilus kanti n. sp.⁹ Epipeltephilus kanti n. sp.⁹ Gonzalez-Ruiz et al. 2012 edentate Holotype: MLP 92-XI-19-7 and others. The type comes from the lower part of the Vivero member
Notoungulata - Toxodontidae	Pisanodon nazari¹ Pisanodon nazari¹ Cabrera and Kraglievich 1931 notoungulate two specimens
Notoungulata - Homalodotheriidae	Chasicotherium rothi n. gen. n. sp.⁸ Chasicotherium rothi n. gen. n. sp.⁸ Cabrera and Kraglievich 1931 notoungulate The taxon is named in Cabrera and Kraglievich (1931; not seen). de Ringuelet adds more material. MLP 26-XI-20-1 (type)
Notoungulata - Mesotheriidae	Typotheriopsis sp.¹, Typotheriopsis chasicoensis⁶ Typotheriopsis sp.¹ Cabrera and Kraglievich 1930 notoungulate nine specimens Typotheriopsis chasicoensis⁶ Cabrera and Kraglievich 1931 notoungulate MCNAM-PV 3211 - 5
Notoungulata - Hegetotheriidae	Paedotherium minor¹, Hegetotheriinae indet.¹, Hemihegetotherium torresi⁶ Paedotherium minor¹ Cabrera 1937 notoungulate many specimens (30). Also ref. 71054: MCNAM-PV 3217 - 20 Hegetotheriinae indet.¹ notoungulate six specimens Hemihegetotherium torresi⁶ Cabrera and Kraglievich 1931 notoungulate MCNAM-PV 3216
Notoungulata - Interatheriidae	Protypotherium distinctum⁵ Protypotherium distinctum⁵ Cabrera and Kraglievich 1931 notoungulate Holotype: MLP 12-2178, right maxilla
Panameriungulata - Macraucheniidae	Cullinia levis¹⁴, Paranauchenia hystata¹⁴ Cullinia levis¹⁴ Cabrera and Kraglievich 1931 placental Paranauchenia hystata¹⁴ placental
Panameriungulata - Proterotheriidae	Proterotheriinae indet.¹, Brachytherium sp.⁶, Neobrachytherium ullumense¹⁴ Proterotheriinae indet.¹ Ameghino 1885 placental partial limb bone Brachytherium sp.⁶ Ameghino 1883 placental MCNAM-PV 3222 - 25 Neobrachytherium ullumense¹⁴ Soria 2001 placental
Rodentia - Hydrochoeridae	"Procardiatherium sp." = Cardiatherium¹, Cardiatheriinae indet.¹ "Procardiatherium sp." = Cardiatherium¹ Ameghino 1883 caviomorph three teeth Cardiatheriinae indet.¹ Kraglievich 1930 caviomorph one tooth
Rodentia - Caviidae	Orthomyctera sp.¹, Procardiomys martinoi¹¹, ? Parodimys sp.¹, Cardiomys sp.¹, Cardiomys leufuensis n. sp.¹² Orthomyctera sp.¹ Ameghino 1889 caviomorph three specimens Procardiomys martinoi¹¹ Pascual 1961 caviomorph ? Parodimys sp.¹ Kraglievich 1932 caviomorph mandible Cardiomys sp.¹ Ameghino 1885 caviomorph two craniodental specimens Cardiomys leufuensis n. sp.¹² Pérez et al. 2018 caviomorph MLP 55-IV-28-11 (type). Also, specimen MLP 29-IX-3-19 (semi-complete post cranial ref 70039)
Rodentia - Chinchillidae	Lagostominae indet.¹, Lagostomus telenkechanum n. sp.¹³ Lagostominae indet.¹ Wiegmann 1832 chinchilid three craniodental specimens Lagostomus telenkechanum n. sp.¹³ Rasia and Candela 2017 viscacha Holotype MLP-Pv 60-VI-18-100 and other specimens
Rodentia - Dinomyidae	? Tetrastylus sp.¹ ? Tetrastylus sp.¹ Ameghino 1886 caviomorph a tooth
Sparassodonta -	Chasicostylus castroi n. gen. n. sp.¹⁰ Chasicostylus castroi n. gen. n. sp.¹⁰ Reig 1957 metatherian MLP 57-XI-9-2, maxilla and dentary, holotype; MLP 55-IV-28-59, right dentary with base of c and alveoli of p1-3, tentatively referred
Sparassodonta - Borhyaenidae	Pseudolycopsis cabrerai¹ Pseudolycopsis cabrerai¹ Marshall 1976 metatherian maxilla with three teeth
Aves
Gruiformes - Phorusrhacidae	Psilopterus colzecus¹ Psilopterus colzecus¹ Tonni and Tambussi 1988 terror bird
Reptilia
Testudines - Testudinidae	Testudinidae indet.⁷ Testudinidae indet.⁷ Batsch 1788 turtle osteoderms
Squamata -	"Carlesia cf. pendolai" = Dicarlesia¹ "Carlesia cf. pendolai" = Dicarlesia¹ lizard one partial skeleton

¹Bondesio et al. 1980; ²Brandoni 2009; ³Brandoni and De Iuliis 2007; ⁴Cabrera 1928; ⁵Cabrera and Kraglievich 1931; ⁶Cerdeno 2000; ⁷de la Fuente et al. 2018; ⁸De Ringuelet 1957; ⁹Gonzalez-Ruiz et al. 2012; ¹⁰Marshall 1981; ¹¹Pascual 1961; ¹²Pérez et al. 2018; ¹³Rasia and Candela 2017; ¹⁴Schmidt et al. 2022; ¹⁵Scillato-Yané 1977