Where: Maule, Chile (34.8° S, 70.6° W: paleocoordinates 37.0° S, 62.2° W)
• coordinate estimated from map
• small collection-level geographic resolution
When: Abanico Formation, Priabonian (38.0 - 33.9 Ma)
• Abanico (= Coya-Machalí) Formation in the greater Río Tinguiririca drainage (~35° S), in the Andean Main Range of central Chile, roughly 20 km west of the border with Argentina. It was recovered from ~20° west-dipping strata near the crest of the divide between the Azufre and Los Helados drainages.
•Although the Abanico Formation is best known for producing early Oligocene mammal fossils (e.g., Flynn et al., 2003a; Hitz et al., 2006; Croft et al., 2008a; Bertrand et al., 2012; Bradham et al., 2015, and references therein), its assemblages span a wide age range, from Eocene to Miocene (Flynn et al., 2003b, 2012; Hitz et al., 2006; Croft et al., 2008b).
•The specimen described below was recovered from the Abanico Formation in the Estero Los Helados, a northern tributary of the Río Tinguiririca immediately west of Río Azufre (fig. 1), in the Andean Main Range of central Chile.
•the specimen was collected from stratigraphically higher levels of the Abanico Formation.
•The detailed stratigraphy and U-Pb and 40Ar/39Ar geochronology of the entire section will be reported elsewhere (Gans et al., in prep.). Here, we describe briefly the geologic context and geochronologic constraints on the fossil-bearing horizon from which SGOPV 6200 was obtained
•the specimen was recovered from a level approximately midway between two primary volcanic deposits for which we have obtained reliable ages. The simplest interpretation is that SGOPV 6200 is between 37 and 36 Ma, with maximum and minimum allowable age ranges of 37.4–35.5 Ma and 36.9– 36.24 Ma, respectively. This inferred age partly overlaps the ~38–37 Ma range estimated for Mustersan SALMA faunas at Gran Barranca in Argentina, based on isotopic dating of the El Rosado and Bed 10 tuffs (Bond and Deschamps, 2010; Madden et al., 2010; Ré et al., 2010; Dunn et al., 2013).
•Therefore, the stratigraphic level at Los Helados that produced SGOPV 6200 appears to pertain to the Mustersan SALMA, congruent with previous interpreta- tions (Croft et al., 2008b; Flynn et al., 2012).
• formation-level stratigraphic resolution
Environment/lithology: terrestrial; tuffaceous, sandy volcaniclastic sediments
•sists of a thick succession of ignimbrites, reworked pyroclastic flows, debris flows, ash and lapilli fall deposits, and fluvial sandstone and conglomerate (fig. 2). All sedimentary units are composed entirely of volcaniclastic detritus—including an abundance of pumice, vitric ash, and well-formed volcanic crystals—suggesting a local source of juvenile tephra and pyroclastic deposits.
•Pumiceous debris flow, volcanic sandstone, and ash/lapelli fall deposits
Size class: macrofossils
Primary reference: R. K. Engelman, J. J. Flynn, P. B. Gans, A. R. Wyss, and D. A. Croft. 2018. Chlorocyon phantasma, a Late Eocene Borhyaenoid (Mammalia: Metatheria: Sparassodonta) from the Los Helados Locality, Andean Main Range, Central Chile. American Museum Novitates 3918:1-22 [P. Mannion/M. Kouvari]more details
Purpose of describing collection: taxonomic analysis
PaleoDB collection 211783: authorized by Philip Mannion, entered by Miranta Kouvari on 27.07.2020
Creative Commons license: CC BY (attribution)
Taxonomic list
| Mammalia | |
Chlorocyon phantasma n. gen. n. sp.
| |