Also known as CB-025
Where: Santa Cruz, Argentina (47.0° S, 71.6° W: paleocoordinates 47.7° S, 66.2° W)
• coordinate estimated from map
• hand sample-level geographic resolution
When: Cerro Boleadoras Formation (Río Zeballos Group), Burdigalian to Burdigalian (20.4 - 13.8 Ma)
• They cite FRANCHI, M., MADDEN, R. H., MAZZONI, M. M. & SWISHER, C. C. III. (in press): Stratigraphy and geochronology of the mammal-bearing middle Miocene "Friasian" of Patagonia. Journ. South Amer. Earth Sci.
•The Cerro Boleadoras Formation contains vertebrate fossils that were respectively assigned to the Santacrucian SALMA (lower Miocene) by Carlini et al. (1993) and Vucetich (1994) and to the Friasian SALMA (upper lower to middle Miocene) by Scillato-Yané et al. (1993) (see Fig. 3). Espinoza et al. (2010) obtained four K/Ar ages between ~16 and 14 Ma for the Zeballos Volcanic Sequence in the top of the Río Zeballos Group (see Fig. 3).
•From Vera et al. 2021: the 16.4Ma succession near the base of the Cerro Boleadoras Formation (Folguera et al. 2018) and the 16–14 Ma interval assigned to the Zeballos Volcanic Sequence on the top (Charrier et al. 1979; Espinoza et al. 2010), a Burdigalian–Langhian age for the Cerro Boleadoras fauna could be inferred
•From Vizcaino et al 2022: Based on a U-Pb detrital zircon maxium age, the lower part of the CBF in the Río Jeinemeni area is estimated at ca. 16.5 Ma, i.e. Burdigalian (Folguera et al., 2018; Fig. 2). This is consistent with the recently obtained early Miocene detrital U-Pb ages for the underlying Río Jeinemeni Formation as well as middle-late Miocene for the overlying Río Correntoso Formation (Aramendía, 2021). The fossil-bearing fluvial deposits of the SCF exposed near Lago Posadas (Fig. 1.B, C) are temporally equivalent to the Río Jeinemeni and Cerro Boleadoras formations, with an age constrained between 18 and 14 Ma based on 40Ar/39Ar tuff ages (Blisniuk et al., 2005), tephrochronology (Perkins et al., 2012) and 87Sr/86Sr ages for the underlying marine deposits (Cuitiño et al., 2015, 2019a). Although no radiometric ages are available for the Cerro Boleadoras and Cerro Plomo area, based on facies similarity, the studied stratigraphic interval is assigned to the lower part of the CBF, whose ~16.5 Ma age is extrapolated from that of the Río Jeinemeni area. Facies similarity is also evident with the nearby SCF in Lago Posadas, allowing to hypothesize that the average sedimentation rate value of 114 m/Myr calculated for that area (Blisniuk et al., 2005) could be extrapolated to the 150 m-thick surveyed succession of the lower part of the CBF, which would range between ca. 16.5-15.1 Ma (Fig. 3).
Environment/lithology: fluvial; lithology not reported
Size classes: macrofossils, mesofossils
Collected by Duke- MPL project, Vizcaino/Bargo team in 1990-1993, 2019-2020
• Specimens here studied were collected by the Duke- MPL project during the 1990s. They are housed at the MLP collection. A new collection of fossils took place in 2019–2020 by the Vizcaino/Bargo team, also housed in the MLP collection
Primary reference: G. J. Scillato-Yané and A. A. Carlini. 1998. Nuevos Xenarthra del Friasense (Mioceno medio) de Argentina. Studia geologica salmanticensia 34:43-67 [P. Mannion/M. Kouvari]more details
Purpose of describing collection: taxonomic analysis
PaleoDB collection 197691: authorized by Philip Mannion, entered by Miranta Kouvari on 22.11.2018, edited by Grace Varnham and Evangelos Vlachos
Creative Commons license: CC BY (attribution)
Taxonomic list
| Reptilia | |
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Chelonoidis cf. gringorum2 Simpson 1942 turtle MPM-PV 19144, four shell fragments; MPM-PV 19145, two shell fragments; MPM-PV 19146, nine shell fragments; MPM-PV 19148, three partial costal plates and a plastron fragment; MPM-PV 19149, left and right associated epiplastra, one plastron fragment. 10 shell fragments; MLP 90-III-5-161, one partial costal, two peripherals, two partial xiphiplastral, 18 shell fragments and a partial femur; MLP 90-III-5-156, four shell fragments
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| Aves | |
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cf. Psilopterus lemoinei2 Moreno and Mercerat 1891 terror bird MPM-PV 19188, right trochlea metatarsi III
Phorusrhacos longissimus2 Ameghino 1887 terror bird MPM-PV 19162, ungual phalanx of the left digit II
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| Mammalia | |
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Propalaehoplophoridae indet.2 Ameghino 1891 edentate MPM-PV 17515, isolated osteoderms and astragalus; MPM-PV 17518, MPM-PV 17521, MPM-PV 17523, MPM-PV 19119, MPM-PV 19122, MPM-PV 19124, MPM-PV 19129, MPM-PV 19131, several isolated osteoderms.
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Prozaedyus proximus2, "Proeutatus cf. oenophorus" = Proeutatus oenophorum2, Stenotatus planus n. sp., Stenotatus cf. planus2
Prozaedyus proximus2 Ameghino 1887 edentate MPM-PV 17520, six articulated osteoderms of the pelvic shield; MPM-PV 17525 two partial osteoderms of the movable band and one fixed; MPM-PV 19126, three broken osteoderms of a movable band.
"Proeutatus cf. oenophorus" = Proeutatus oenophorum2 Ameghino 1887 edentate MPM-PV 17513, two fixed osteoderms, and one movable; MPM-PV 17519, seven osteoderms; MPM-PV 19117, two osteoderms, one fixed and one movable; MPM-PV 19121, five fixed osteoderms.
Stenotatus cf. planus2 Scillato-Yané and Carlini 1998 edentate MPM-PV 17514, two fragments of the pelvic shield, MPM-PV 17516, three osteoderms; MPM-PV 19118, 12 fixed osteoderms, one movable and two fragments; MPM-PV 19120 carapace and postcrania articulated; MPM-PV 19123, two osteoderms, one fixed and one movable; MPM-PV 19128, 19 fixed osteoderms, one movable and 7 fragments; MPM-PV 19130, two movable osteoderms. MPM-PV 19189, four fixed osteoderms.
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Peltephilus sp.2 Ameghino 1887 edentate MPM-PV 17524, partial fixed osteoderm; MPM-PV 19125, two osteoderms from the carapace (fixed and movable), and two from the cephalic shield.
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Vetelia puncta2 Ameghino 1891 armadillo MPM-PV 17517, three fixed osteoderms; MPM-PV 17522, two fixed osteoderms and fragments, MPM-PV 17526, 10 fixed osteoderms, 20 fragments of fixed and movable osteoderms; MPM-PV 19127, one fixed osteoderm, and two fragments of osteoderms.
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Megatherioidea indet.2 Gray 1821 edentate MPM-PV 19132, right astragalus, partial left calcaneus, ungual phalanx, and carpals/tarsals; not associated; MPM-PV 19133, left astragalus, three partial ungual phalanges, carpal/tarsal, four vertebrae; not associated; MPM-PV 19134, three partial ungual phalanges; not associated; MPM-PV 19135, four ungual phalanges; not associated; MPM-PV 19136, proximal calcaneum, carpals/tarsals; not associated; MPM-PV 19137, partial humeral diaphysis, carpals/tarsals, ungual phalanx, vertebra; not associated
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Anisolophus sp.2 Burmeister 1885 placental MPM-PV 19151, left mandibular fragment with posterior roots (broken) of p4 and m1 partially preserved.
Thoatherium minusculum2 Ameghino 1887 placental MPM-PV 19150, left mandibular fragment with dp2–dp3.
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Caviomorpha indet.2 caviomorph The specimen MLP 90-III-5-19 (90-291), a right mandibular fragment with m1-m2, MPM-PV 19174, consists in a dentary fragment with m1-m3, very deteriorated. However, the thick enamel layer is very similar to that of MLP 90-III-5-19.
Eocardia montana2 Ameghino 1887 caviomorph MLP 90-III-5-12 (90-332), left dentary fragment with dp4-m1. MLP 91-I-10-1 (91-517), right dentary fragment with m1-m2; MLP 91-I-10-8a, b (91-531), a) isolated m1 or m2, and b) isolated left M1 or M2.
Neoreomys australis2 Ameghino 1887 caviomorph MLP 90-III-5-5 (90-336), isolated left dp4; MLP 90-III-5-17 (90-338), right M1 or M2, right broken M1 or M2, left lower molar and left p4; MLP 90-III-5-21 (90-294), anterior portion of left p4; MLP 90-III-5-22 (90-380), left p4, two isolated left M1or M2, and a broken incisor; MLP 90-III-5-30 (90-439), P4; MLP 90-III-5-39 (90-258), right mandibular fragment labially broken with a fragment of a p4; MLP 91-I-10-2a (91-586), right m3; MLP 91-I-10-4 (91-587), right mandibular fragment with p4-m3; MLP 91-I-10-11(91-531), left m1; MLP 91-I-10-2b (91-586), isolated left m1 or m2; MLP 91-I-10-13 (91-596), left mandibular fragment with m2; MLP 91-I-10-19 (91-567), right upper molar; MPM-PV 19168, right mandibular fragment with p4-m3; MPM-PV 19171, right m1 or m2; MPM-PV 19175, left mandibular fragment with m1 and roots of p4; MPM-PV 19176, right maxillary fragment with M2-M3 and broken M1, MPM-PV 19177, left maxillary fragment with M2-M3; MPM-PV 19178, left mandibular fragment with m2; MPM-PV 19179, right mandibular fragment with dp4-m2.
Luantus propheticus2 Ameghino 1899 caviomorph MLP 91-I-10-8c, d, e (91-531), c) right m1 or m2, d) right m1 or m2, e) small right dentary fragment with m3.
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Pliolagostomus notatus2 Ameghino 1887 chinchilid MLP 90-III-5-13 (90-341), left maxillary fragment with M1-M2; MLP 90-III-5-33 (90-465), three upper isolated molars: a) right P4, b) left M1 or M2, and c) right M1 or M2; MLP 90-III-5-34 (90-464), left dentary fragment with p4-m2; MLP 90-III-5-36 (90-403), isolated right P4?
Prolagostomus pusillus2 Ameghino 1887 chinchilid MLP 90-III-5-11 (90-288), left dentary fragment with i, m1-m3; MLP 90-III-5-14 (90-343), two right p4 and m1 or m2; MLP 90-III-5-16 (90-342), right maxillary fragment with M1-M2; MLP 90-III-5-25 (90-244), left dentary fragment with i and p4; MLP 90-III-5-28 (90-254), fragment of m1 or m2; MLP 90-III-5-29 (90-440), isolated molars: a) left m1 or m2 and b) left P4?; MLP 91-I-10-2c (91-586), right dentary fragment with p4; MLP 91-I-10-54a (91-534), left dentary fragment with p4 erupting (and broken roots of dp4)
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Perimys sp.2 Ameghino 1887 caviomorph MPM-PV 19170, left maxillary fragment with M1-M2; MPM-PV 19172 right m1 or m2; MPM-PV 19167, molar in concretion
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Adelphomyinae indet.2 Patterson and Pascual 1968 spiny rat MPM-PV 19173, left dentary fragment with m3.
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? Acarechimys sp.2 Patterson 1965 caviomorph MLP 90-III-5-1 (90-287), right mandibular fragment with m2.
Acarechimys minutus2 Patterson and Pascual 1967 caviomorph MLP 91-I-10-5 (91-530a), right mandibular fragment with m1-m2.
Acarechimys minutissimus2 Ameghino 1887 caviomorph MLP 90-III-5-4 (90-335), right mandibular fragment with m1-m2.
Stichomys sp.2 Ameghino 1887 caviomorph MLP 91-I-10-9 (91-547), left dentary fragment with p4-m1; MLP 91-I-10-10 (91-547), right dentary fragment with p4-m2; MLP 91-I-10-16 (91-565), left dentary fragment with p4-m2; MLP 91-I-10-18 (91-565), left dentary fragment with m1-m3.
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Protypotherium sp.2, Protypotherium aff. colloncurensis1, Interatheriinae "gen. sp. A"1, Interatheriinae "gen. sp. B"1, Boleatherium praeludium n. gen. n. sp.1, Interatherium sp.2
Protypotherium sp.2 Ameghino 1882 notoungulate MPM-PV 19152, four dentary fragments: right dentary with m2-m3, right dentary with p3-p4?, left dentary with p4-m2, left dentary with p4-m3; MPM-PV 19153, two dentary fragments: left dentary with m1-m3, right dentary with p4-m1; MPM-PV 19155, dentary and maxilla fragments: symphysis and right dentary with p2-p3 and m1-2, symphysis and right dentary with incisors, canine and p1-p2 broken, right dentary m3, right dentary with m2? broken, right dentary p2-p3?, left dentary with p2-p4 and m1, left dentary with p3-m2 broken, left dentary with m2-m3 broken, juvenile left dentary with molariforms, left maxilla with P3-M2 broken; MPM-PV 19156, left dentary fragment with p2-p3; MPM-PV 19157, mandibular symphysis with left i1-i3, and right i1-i3, c1, and p1-p4; MPM-PV 19160, left maxilla fragment with fragment of P4 and M1-M2, and postcranial elements associated; MPM-PV 19182, two dentary fragments: right dentary with m1-m2?, right dentary with premolar?; MPM-PV 19186, two dentary fragments: right dentary with p3-m2, right dentary with i1-i3,c,p1-p4 and m1 (all broken), juvenile right dentary with three molariforms (p4-m2?).
Protypotherium aff. colloncurensis1 Vera et al. 2017 notoungulate MLP 91-I-10-34 to 41l; MLP 91-I-10-34 and 37; MLP 91-I-10-35, 36 and 38; MLP 91-I-10-39 and 41; MLP 91-I-10-40; MLP 90-III-5-166
Boleatherium praeludium n. gen. n. sp.1 Vera et al. 2021 notoungulate Holotype: MLP 90-III-5-165: lot composed of several pieces belonging to the same individual; MLP 90-III-5-170a, left astragalus and calcaneus, and right calcaneus lacking the distal part
Interatherium sp.2 Ameghino 1887 notoungulate MPM-PV 19161, left dentary fragment with p2-p4; MPM-PV 19183, two right dentary fragments, one with p3 (?) and another with p1-p3 (?)
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Pachyrukhos cf. moyani2 Ameghino 1885 notoungulate MPM-PV 19159, six fragmentary dentaries: right dentary with p4-m3, right dentary with p2-m2, right dentary with p2-m2, right dentary with m1-m2, right dentary with m2 and left dentary with p3-m2; MPM-PV 19181, left dentary fragment with p2-p
Hegetotherium mirabile2 Ameghino 1887 notoungulate MPM-PV 19158, two specimens not associated: left dentary fragment with m2-m3; and right dentary fragment with m3; MPM-PV 19180, left dentary with m1-m2; MPM-PV 19184, associated left maxilla with P4-M3 and right maxilla with P3-M2
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| Amphibia | |
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cf. Calyptocephalella sp.2 Strand 1926 helmeted water toad MPM-PV 19139, two partial vertebrae; MPM-PV 19140, several fragmentary bones, including skull, vertebrae, humerus and numerous unidentified elements; MPM-PV 19141, partial fragmentary unprepared skeleton; MPM-PV 19142, partial vertebra; MPM-PV 19143, three partial vertebrae and posterior portion of ilion
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