# Paleobiota of the Cañadón Asfalto Formation

The Cañadón Asfalto Formation is a geological formation which dates to the Toarcian age of the Early Jurassic period of Argentina. The rocks of the formation preserve a diverse biota, including plants, dinosaurs, invertebrates, mammals and pterosaurs, among others. The formation is divided into two members: the lower Las Chacritas Member, and the overlying Puesto Almada member, though the latter has also been assigned to the overlying Cañadón Calcáreo Formation by some authors. The members are typically composed of fluvial-lacustrine deposits consisting of sandstones and shales, with a limestone carbonate evaporitic sequence also being present in the lower of the two.

## Invertebrates

| Color key Taxon Reclassified taxon Taxon falsely reported as present Dubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon | Notes Uncertain or tentative taxa are in small text; crossed out taxa are discredited. |

### Demospongiae

Palaeospongillidae reported from the Cañadon Asfalto Formation :
| Genus | Species | Location | Stratigraphic position | Material | Notes | Images |
| Palaeospongilla | P. chubutensis | Estancia Fossati locality | Las Chacritas Member | Isolated Specimens | A freshwater (Lacustrine) member of Palaeospongillidae (Spongillida Sponges). Represents the main lacustrine bottom inhabitant of the Chacritas Paleolake | Example of the living genus Spongilla. The genus Palaeospongilla was likely similar |

### Crustacea

Crustacea reported from the Cañadon Asfalto Formation :
| Genus | Species | Location | Stratigraphic position | Material | Notes | Images |
| Carapacestheria | C. taschi | Cañadón Asfalto Cañadón Lahuincó Cerro Bayo | Las Chacritas Member Puesto Almada Member | Isolated Valves | A freshwater (Lacustrine) member of Eosestheriidae (Spinicaudatan). Originally identified as Cyzicus (Euestheria) taschi. This genus is found in identical alkaline lacustrine settings in the also Toarcian Mawson Formation of Antarctica | |
| Congestheriella | C. rauhuti | Sierra de la Manea Estancia El Torito Cañadón Los Chivos | Puesto Almada Member | Isolated Valves | A freshwater (Lacustrine) member of Afrograptidae (Spinicaudatan). Given the stratigraphic uncertainty, it may come from the Cañadón Calcáreo Formation. | |
| Darwinula | D. magna D. spp. | Cañadón Asfalto Cañadón Lahuincó Cerro Bayo Cañadón Asfalto Quebrada Subsidiaria Estancia el Torito | Las Chacritas Member Puesto Almada Member | Isolated Valves | A freshwater (Lacustrine) member of Darwinulidae (Ostracod). | |
| Eosolimnadiopsis | E. spp. | Cerro Cóndor Estancia Fossati | Las Chacritas Member | Isolated Valves | A freshwater (Lacustrine) member of Palaeolimnadiopseidae (Spinicaudatan). | |
| Euestheria | E. volkheimeri | Cerro Cóndor Cerro Bayo Alice Creek Quebrada Subsidiaria | Las Chacritas Member Puesto Almada Member | Isolated Valves | A freshwater (Lacustrine) member of Euestheriidae (Spinicaudatan). | |
| Lioestheria | C. (Lioestheria) sp. B C. (Lioestheria) sp. C | Cañadón Las Chacritas Colan Conhué Alice Creek | Las Chacritas Member Puesto Almada Member | Isolated Valves | A freshwater (Lacustrine) member of Fushunograptidae (Spinicaudatan). | Extant example of the Genus |
| Mandelstamia | M.? spp. | Estancia El Torito | Puesto Almada Member | Isolated Valves | A freshwater (Lacustrine) member of Limnocytheridae (Ostracodan). Given the stratigraphic uncertainty, it may come from the Cañadón Calcáreo Formation | |
| Metacypris | M. sp. | Estancia El Torito | Puesto Almada Member | Isolated Valves | A freshwater (Lacustrine) member of Loxoconchidae (Ostracodan). Given the stratigraphic uncertainty, it may come from the Cañadón Calcáreo Formation. | |
| Penthesilenula | P. magna P. sarytirmenensis | Cañadón de la Angostura Estancia El Torito | Las Chacritas Member Puesto Almada Member | Isolated Valves | A freshwater (Lacustrine) member of Darwinulidae (Ostracodan). These species are characteristic of the Middle Jurassic of northern China and where used to correlate the age of the beds | |
| Pseudestherites | P. sp. | Estancia El Torito Cañadón Los Chivos | Puesto Almada Member | Isolated Valves | A freshwater (Lacustrine) member of Antronestheriidae (Spinicaudatan). Given the stratigraphic uncertainty, it may come from the Cañadón Calcáreo Formation. | |
| Theryosinoecum | T. barrancalensis minor | Estancia El Torito | Puesto Almada Member | Isolated Valves | A freshwater (Lacustrine) member of Cytheroidea (Ostracodan). Given the stratigraphic uncertainty, it may come from the Cañadón Calcáreo Formation. | |
| Timiriasevia | T. sp. | Estancia El Torito | Puesto Almada Member | Isolated Valves | A freshwater (Lacustrine) member of Limnocytheridae (Ostracodan). Given the stratigraphic uncertainty, it may come from the Cañadón Calcáreo Formation. | |
| Wolfestheria | W. patagoniensis W. smekali | Cañadón Asfalto Cañadón Lahuincó Estancia La Sin Rumbo | Las Chacritas Member Puesto Almada Member | Isolated Valves | A freshwater (Lacustrine) member of Fushunograptidae (Spinicaudatan). | |

### Mollusca

Mollusca reported from the Cañadon Asfalto Formation :
| Genus | Species | Location | Stratigraphic position | Material | Notes | Images |
| Corbicula | C. spp. | Cerro Cóndor Cerro Bayo Estancia El Torito | Las Chacritas Member Puesto Almada Member | Isolated Shells | A freshwater (Lacustrine) member of Corbiculidae (Bivalve). | Extant example of the Genus |
| Cyanocyclas | C. spp. | Cerro Cóndor Cerro Bayo Estancia El Torito | Las Chacritas Member Puesto Almada Member | Conchas Aisladas | A freshwater (Lacustrine) member of Corbiculidae (Bivalve). | |
| Diplodon | D. spix D. cf.matildensis D. cf.spix D. spp. | Cañadón Asfalto Cerro Caracoles Las Chacritas Cañadón Lahuincó Cañadón Miyanao Cerro Cóndor Cerro Bayo Alice Creek Quebrada Subsidiaria Estancia El Torito | Las Chacritas Member Puesto Almada Member | Isolated Shells | A freshwater (Lacustrine) member of Unionidae (Bivalve). The most abundant Bivalve genus on the Formation. Represents also some of the smallest-sized specimens recorded in the Mesozoic, what can be explained by potential environment stress. | Extant example of the Genus |
| Nayadidae | Indeterminate | Cañadón Asfalto Cañadón Lahuincó | Las Chacritas Member | Isolated Shells | A freshwater (Lacustrine) member of Unionidae (Bivalve). | |
| Palaeomutela | P. spp. | Las Chacritas | Las Chacritas Member | Isolated Shells | A freshwater (Lacustrine) member of Palaeomutelidae (Bivalve). | |
| Potamolithus | P.? spp. | Cañadón Asfalto Cerro Caracoles Las Chacritas Cañadón Lahuincó | Las Chacritas Member | Isolated Shells | A freshwater (Lacustrine) member of Tateidae (Snail). | Extant example of the Genus |
| Sphaeriidae | Indeterminate | Cañadón Asfalto | Las Chacritas Member | Isolated Shells | A freshwater (Lacustrine) member of Sphaeriida (Bivalve). | |
| Viviparus | V. spp. | Cañadón Asfalto Cerro Caracoles Cañadón Lahuincó Cañadón Asfalto Quebrada Subsidiaria Estancia El Torito | Las Chacritas Member Puesto Almada Member | Isolated Shells | A freshwater (Lacustrine) member of Viviparidae (Snail). | Extant example of the Genus |

### Insecta

Insect eggs of unknown affinity were reported from several layers of the Estancia Fossati locality.
Insects reported from the Cañadon Asfalto Formation :
| Genus | Species | Location | Stratigraphic position | Material | Notes | Images |
| Chironomidae | Indeterminate | Gan Gan | Puesto Almada Member | Head capsules | Indeterminate Bittacidae (Migdes) remains, associated with lacustrine facies. Given the stratigraphic uncertainty, it may come from the Cañadón Calcáreo Formation | Extant member of the Family |
| Coleoptera | Indeterminate | Cerro Cóndor Estancia Fossati Estancia El Torito Estancia La Sin Rumbo | Las Chacritas Member Puesto Almada Member | Elytra and body remains | Indeterminate Beetle remains, associated with lacustrine facies | Extant example of the Group |
| Conchindusia | C. isp. | Cerro Cóndor Gan Gan | Las Chacritas Member Puesto Almada Member | Imprints or compressed moulds of larval cases | Indeterminate Trichoptera (Caddisflies) Ichnofossils, associated with lacustrine facies. Larval cases made of conchostracan shells | |
| Heteroptera | Indeterminate | Cerro Cóndor Estancia Fossati Estancia El Torito Estancia La Sin Rumbo | Las Chacritas Member Puesto Almada Member | Fragmentary wings | Indeterminate Heteroptera remains, associated with lacustrine facies | Extant example of the Group |
| Neorthophlebidae | Indeterminate | Gan Gan | Puesto Almada member | Wings and parts of body | Indeterminate Bittacidae (Scorpionfly) remains, associated with lacustrine facies. Given the stratigraphic uncertainty, it may come from the Cañadón Calcáreo Formation | |
| Ostracindusia | O. isp. | Cerro Cóndor Gan Gan | Las Chacritas Member Puesto Almada Member | Imprints or compressed moulds of larval cases | Indeterminate Trichoptera (Caddisflies) Ichnofossils, associated with lacustrine facies. Larval cases made of ostracodan shells | |
| Terrindusia | T. isp. | Cerro Cóndor Estancia Fossati Gan Gan | Las Chacritas Member Puesto Almada Member | Imprints or compressed moulds of larval cases | Indeterminate Trichoptera (Caddisflies) Ichnofossils, associated with lacustrine facies. Larval cases made of clasts or terrigenous particles | |
| Trichoptera | Indeterminate | Cerro Cóndor Estancia Fossati Estancia El Torito Estancia La Sin Rumbo | Las Chacritas Member Puesto Almada Member | Wings and larval cases | Indeterminate Trichoptera (Caddisflies) remains, associated with lacustrine facies | Extant example of the Group |

## Vertebrates
### Fish

Actinopteri reported from the Cañadon Asfalto Formation :
| Genus | Species | Location | Stratigraphic position | Material | Notes | Images |
| Archaeomaenidae | Indeterminate | Cerro Cóndor Cañadón Asfalto Cañadón Miyanao Estancia Fossati Localidad de Canela Cañadón Asfalto Quebrada Subsidiaria | Las Chacritas Member | Isolated large median fin & Isolated Scales | A freshwater (Lacustrine) member of Archaeomaenidae (Teleostei). Maybe related to the genus Oreochima, coming from layers coeval, coregional, and of identical deposition of the Mawson Formation of Antarctica | Example of member of the family Archaeomaenidae, Archaeomaene |

### Amphibians

Amphibians reported from the Cañadon Asfalto Formation :
| Genus | Species | Location | Stratigraphic position | Material | Notes | Images |
| Notobatrachus | N. degiustoi N. reigi Cf.N. spp. | Cañadon Bagual Zitarrosa Cerro Cóndor Canela Queso Rallado | Las Chacritas Member | Many articulated, mostly complete skeletons Most of a partially articulated skeleton and skull | An early frog of the family Notobatrachidae. Notobatrachus degiustoi can be distinguished from N. reigsi by features of the skull. The presence of this anuran in several locations suggests local proliferation linked with lacustrine bodies | |

### Turtles

Turtles reported from the Cañadon Asfalto Formation :
| Genus | Species | Location | Stratigraphic position | Material | Notes | Images |
| Condorchelys | C. antiqua C. cf.antiqua C. spp. | Queso Rallado Cañadon Bagual Chucrut Canela facies | Las Chacritas Member | Holotype: Most of a skull, carapace, and plastron. MPEF-PV 3163, left humerus MPEF-PV 3164, costal plate | A stem turtle (Mesochelydian) outside both extant groups, closely related with Kayentachelys aprix of North America and Indochelys spatulata of India. Likely occupied aquatic or semiaquatic niches. | |
| Testudinata | Indeterminate | Canela facies | Las Chacritas Member | plastrons | Indeterminate Turtle remains | |

### Lepidosaurs

Lepidosaurs reported from the Cañadon Asfalto Formation :
| Genus | Species | Location | Stratigraphic position | Material | Notes | Images |
| Sphenocondor | S. gracilis | Queso Rallado | Las Chacritas Member | Dentary | A Sphenodontian Rhynchocephalian, closely related with Godavarisaurus from the almost coeval Jurassic Kota Formation of India, maybe part of an endemic Gondwanan clade. | |

### Crocodylomorpha

Crocodyliformes reported from the Cañadón Asfalto Formation :
| Genus | Species | Location | Stratigraphic position | Material | Notes | Images |
| Crocodylomorpha | Indeterminate | Queso Rallado | Las Chacritas Member | Several isolated remains | Indeterminate crocodylomorph remains that represent among the most complete vertebrates linked with lacustrine facies. | |

### Pterosaurs

Pterosaurs reported from the Cañadón Asfalto Formation :
| Genus | Species | Location | Stratigraphic position | Material | Notes |
| Allkaruen | A. koi | Canadón Carrizal | Las Chacritas Member | A braincase, as well as a mandible and cervical vertebrae. | A pterosaur either related with Breviquartossa or maybe even a sister group of monofenestratan (Wukongopteridae + Pterodactyloidea) pterosaurs |
| Ctenochasmatidae? | Indeterminate | Queso Rallado | Not Determined | Isolated tooth | Resembles the teeth of Pterodaustro. The exact provenance of the specimen is unknown |
| Melkamter | M. pateko | Queso Rallado | Las Chacritas Member | Partial skull and associated postcranial elements | A monofenestratan pterosaur, representing the oldest known record of this clade |
| Scaphognathinae? | Indeterminate | Las Chacritas | Las Chacritas Member | Uncatalogued specimens, several mandibles, braincase, shoulder girdle, two humeri, several wing-finger phalanges | Indeterminate remains of a pterosaur, possibly a rhamphorhynchoid with a wingspan of about 1.5–2 metres (4.9–6.6 ft). The mandible morphology is similar to scaphognathines. |

### Theropods

During a campaign conducted in early 2021, remains of a large theropod dinosaur were found near the town of Las Chacritas. In 2020 a new fossil locality was found, named Cañadón de las Huellas due to the large number of sauropod, and probably theropod, footprints on one of the canyon walls. In the same locality in 2021, articulated remains where recovered and represent at least one sauropod and one large theropod. At least four theropod morphotypes, including one with ceratosaur and another with Piatnitzkysauridae affinities, are known from the Cañadón Bagual.
Theropoda reported from the Cañadón Asfalto Formation :
| Genus | Species | Location | Stratigraphic position | Material | Notes |
| Asfaltovenator | A. vialidadi | Cerro Condor | Las Chacritas Member | Nearly compete skull and largely complete front half of the skeleton forward of the hips, distal pubis and fermur and proximal fibula and tibia, partial foot | A probable early member of Allosauroidea |
| Averostra | Indeterminate | Cerro Cóndor Puesto el Quemado Cerro Bayo | Las Chacritas Member | Isolated teeth: MPEF BA 182/08, BA 40/08, BA 09/80, BA 88/08, BA 252G+165/08 A, BA 252G+165/08 B, BA 252G+165/08 C | Theropod dinosaur teeth that resemble those assigned to the families Ceratosauridae, Megalosauridae and Abelisauridae |
| Ceratosauridae | Indeterminate | Cañadon Bagual | Las Chacritas Member | A dentary with teeth in situ, MPEF-PV 6775 | It resembles the dentary of Ceratosaurus |
| Condorraptor | C. currumili | Las Chacritas | Las Chacritas Member | Partial articulated skeleton | A relative of Piatnitzkysaurus from the same formation, and a possible junior synonym of it as well. |
| Dromaeosauridae | Indeterminate | Cerro Cóndor Puesto el Quemado Cerro Bayo | Las Chacritas Member | Isolated Teeth: MEPF BA 61/08, BA 103/08, BA 32/08 A, BA 32/08 B, BA 104/08, BA 226B/08, PV 3498, BA 29/08, BA51/08, BA 270/08 a, BA 270/08 b, BA 270/08 c | Theropod dinosaur teeth that resemble those assigned to the family Dromaeosauridae. Alternatively, they could belong to basal members of Coelurosauria |
| Eoabelisaurus | E. mefi | Jugo Luco | Las Chacritas Member | A nearly complete articulated skeleton | A Neoceratosaur, that was suggested to be a basal member of Abelisauria, but also a member of Ceratosauridae |
| Megalosauridae | Indeterminate | Cerro Cóndor Puesto el Quemado Cerro Bayo | Las Chacritas Member | Isolated Teeth: MPEF PV 1175, BA 66/08, PV 1356, PV 1357 | Theropod dinosaur teeth that resemble those assigned to the family Megalosauridae. |
| Neotheropoda | Indeterminate | Cerro Cóndor Puesto el Quemado Cerro Bayo | Las Chacritas Member | Isolated Teeth: MPEF BA 68/08, BA 92/08, PV 3499, BA 68/08, BA 183/08 | Theropod dinosaur teeth that resemble those assigned to basal neotheropods, such as members of Coelophysoidea. |
| Piatnitzkysauridae | Indeterminate | Cerro Cóndor Puesto el Quemado Cerro Bayo | Las Chacritas Member | Isolated Teeth & Cranial remains: MPEF 1717 CC 205, PV 3440A A, PV 3440A B, PV 3440A C, PV 3440A D, PV 3440A E, PV 3440A F, PV 3440A G | Theropod dinosaur teeth that resemble those assigned to members of Piatnitzkysauridae. |
| Piatnitzkysaurus | P. floresi | Cerro Cóndor South | Las Chacritas Member | Two "fragmentary skulls with associated postcranium." | Possible senior synonym of Condorraptor from the same formation. |
| Spinosauridae | Indeterminate | Cerro Cóndor | Las Chacritas Member | Isolated Teeth : MEPF PV 1350 | Theropod dinosaur teeth resembling those assigned to members of Spinosauridae. Alternatively, they could belong to members of Ceratosauria |
| Tetanurae | Indeterminate | Cerro Cóndor Puesto el Quemado Cerro Bayo | Las Chacritas Member | Isolated Teeth : MEPF BA 84/08, BA 49/08 A, BA 49/08 B, BA 64/08, BA 65/08, BA 266/07 | Theropod dinosaur teeth that resemble with those assigned to members of Megalosauridae and Dromaeosauridae |
| Theropoda | Indeterminate | Cerro Cóndor | Las Chacritas Member | Isolated Teeth : MPEF PV 1640 | "Outlier" tooth that doesn't fit in any previously known morphotype, maybe due to preservation |
| Theropodipedia | Indeterminate | Cerro Cóndor | Las Chacritas Member | Footprints | Possible theropod footprints, unassigned to any concrete ichnogenus |

### Sauropodomorphs

A sediment tubular shaped mass enriched in organic matter, closely associated within the ventral area of articulated remains of a sauropod, was recovered at Cerro Condor, composed of a high concentration of pollen grains & cuticular fragments, mainly leaves of two morphotypes (Araucariaceae and Cheirolepidaceae), probably representing the gut contents of the sauropod, inferring a conifer-based diet.
Sauropodiformes reported from the Cañadón Asfalto Formation :
| Genus | Species | Location | Stratigraphic position | Material | Notes |
| Bagualia | B. alba | Cañadon Bagual | Las Chacritas Member | The partial skeletons of three individuals | An early member of Eusauropoda, related with the African genus Spinophorosaurus |
| Diplodocidae | Indeterminate | Cerro Condor Sur | Las Chacritas Member | MACN-CH 934: axial neural arches and spines, an ilium, a pubis, ?two or ?three ischia, and two maxillae | This specimen shows strong Diplodocidae affinities, yet it has been considered either a derived non-neosauropodan eusauropod (having resemblance with Lapparentosaurus in some characters) or even a basal neosauropod (also resembling Haplocanthosaurus) |
| Eusauropoda | Indeterminate | Cerro Condor Sur | Las Chacritas Member | MACN-CH 230: three dorsal vertebrae | Likely a eusauropod, possibly a cetiosaurid. Smaller than other sauropod taxa found in the formation. |
| Patagosaurus | P. fariasi | Cerro Condor | Las Chacritas Member | Many specimens, including a partial skull. | A non-neosauropodan eusauropodan member of Cetiosauridae. This genus represents the most abundant sauropod in the formation |
| Sauropodiformes | Indeterminate | Queso Rallado, near Cerro Cóndor | Las Chacritas Member | Isolated Teeth: MPEF-PV 10860 | An indeterminate Sauropodiform or a very basal sauropod or even dental material of Volkheimeria. |
| Sauropoda | Indeterminate | Cerro Condor Sur | Las Chacritas Member | MACN-CH 219, 223(+221), 231 | Too fragmentary to be ascribed to any taxon, currently classified as Sauropoda indet. |
| Titanosauriformes | Indeterminate | Queso Rallado, near Cerro Cóndor | Las Chacritas Member | Isolated Teeth: MPEF-PV 10606 | An indeterminate Titanosauriform. It can be alternatively a basal Eusauropod. Possible relationships with Atlasaurus |
| Volkheimeria | V. chubutensis | Cerro Cóndor South | Las Chacritas Member | "Partial skeleton consisting of presacral and sacral vertebrae, pelvis, [and] hindlimb." | Either a gravisaur or a sister taxon of the Indian genus Barapasaurus |

### Ornithischians

Ornithischians reported from the Cañadón Asfalto Formation :
| Genus | Species | Location | Stratigraphic position | Material | Notes |
| Cerapoda | Indeterminate | Queso Rallado | Las Chacritas Member | Isolated ungual phalanx and Isolated Teeth: MPEF-PV 3818, MPEF-PV 3824, MEPF-PV 3820, MEPF-PV 3825, MEPF-PV 10861, MPEF-PV 10823, MPEF-PV 3821 & MPEF-PV 10864 | An indeterminate Cerapodan with resemblances with Hypsilophodon. Some of the referred remains have been reclassified as Manidens material |
| Heterodontosauridae | Indeterminate | Queso Rallado | Las Chacritas Member | Metapodials, caudal vertebrae, and isolated phalanges: MPEF-PV 3826 | heterodontosaurid that cannot be compared with Manidens due to the lack of overlapping fossils. |
| Manidens | M. condorensis | Queso Rallado Sitio Frenguelli Sitio Canela | Las Chacritas Member | Partial articulated specimen, skull & associated elements as well referred isolated teeth: MPEF-PV 3809, MPEF-PV 3211, MPEF-PV 3808, MPEF-PV 10867, MPEF-PV 1719, MPEF-PV 1786, MPEF-PV 1718, MPEF-PV 3810, MPEF-PV 3811, MPEF-PV 3812, MPEF-PV 3813, MPEF-PV 3814, MPEF-PV 3815, MPEF-PV 3816, MPEF-PV 10866 | A primitive and small heterodontosaurid. Fossils attributed to this genus may have been at least partially arboreal. Principal component analysis found that the feet of Manidens were most similar to those of tree-perching birds. |
| Ornithischia | Indeterminate | Queso Rallado | Las Chacritas Member | Isolated teeth: MPEF-PV 3817, MPEFPV 3819, MPEF-PV 3822. | Not referable to any taxa beyond Ornithischia Indet. |

### Mammals

Mammals reported from the Cañadón Asfalto Formation :
| Genus | Species | Location | Stratigraphic position | Material | Notes |
| Allotheria | Indeterminate | Queso Rallado | Las Chacritas Member | Isolated Teeth | An Allotherian whose affinities hasn't been tested |
| Argentoconodon | A. fariasorum | Queso Rallado | Las Chacritas Member | MPEF-PV2362, fragmentary left maxilla, MPEF-PV2363 partial skeleton, MPEFPV2364 isolated complete right upper last molariform | A volaticotherian (Alticonodontinae), closely related to the Asian genus Volaticotherium, having similar postcraneal appearance, indicating possible gliding capabilities, yet better material is needed to prove it. |
| Asfaltomylos | A. patagonicus | Queso Rallado | Las Chacritas Member | MPEF PV 1671, complete lower maxilla | An Australosphenidan, related to Henosferus in Henosferidae. |
| Condorodon | C. spanios | Queso Rallado | Las Chacritas Member | MPEF-PV 2365, isolated complete lower left molariform | An "amphilestid" triconodont, related with the late jurassic African Tendagurodon. |
| Henosferus | H. molus H. sp. | Queso Rallado Canela | Las Chacritas Member | MPEF 2353 right lower jaw, MPEF 2354 Left lower jaw, MPEF 2357 Left lower jaw, referred MPEF 2355 isolated upper premolar | An Australosphenidan, related to Asfaltomylos in Henosferidae, being twice as large as this last one. |

## Fungi

| Genus | Species | Location | Stratigraphic position | Member | Material | Ecogroup | Palaeoclimate requirements | Notes |
| Annella | A. capitata | Central Patagonia | Cañadon Lahuincó | Las Chacritas Member | Hypae and Miospores | Unknown: either Aquatic (Freshwater) or Parasitic | Unknown, suggested highly seasonality | A Fungus of uncertain relationships. This species is recovered in both coal seams and proximal prodelta sediments, making the assignation of a biome complex. |

## Plants

According to a palynological study the dominant pollen was produced by the conifer families Cheirolepidiaceae (Classopollis) and Araucariaceae (mainly Araucariacites and Callialasporites), suggesting that warm-temperate and relatively humid conditions under highly seasonal climate prevailed during the depositional times of the unit. The abundance of Botryococcus supports the presence of a shallow lake with probably saline conditions. Locally, the Cañadón Asfalto represents a more poor record of the floras seen in the undeliying Lonco Tapial Formation, with its closest floras found on the Antarctic Peninsula Ellsworth Land Volcanic Group at Potter Peak, sharing Brachyphyllum spp. and Elatocladus confertus.

### Phytoplankton

Possible freshwater "calcareous algae", associated with conifer shoots and aquatic invertebrates, have been reported from Cerro Caracoles.
| Genus | Species | Location | Member | Material | Ecogroup | Palaeoclimate requirements | Notes | Images |
| Botryococcus | B. sp. cf. B. braunii B. spp | Cañadon Lahuincó Cañadón Caracoles Cerro Bandera | Las Chacritas Member Puesto Almada Member | Algae | Aquatic (freshwater); Alkaline indicator | Highly seasonal climate | A freshwater algae of the family Botryococcaceae. This genus is the main indicator, due to its abundance, of the presence of a shallow lake with probably saline conditions, reaching in some samples about 96 to 70%. | Extant specimen |
| Leiosphaeridia | L. sp. | Cañadon Lahuincó Cañadón Caracoles | Las Chacritas Member | Zygospores | Aquatic (freshwater) | Temperate to warm; seasonal climate | Algae or Algae Acritarch of the family Prasinophyceae. | |
| Ovoidites | O. spp. | Cañadon Lahuincó Cañadón Caracoles | Las Chacritas Member | Zygospores | Aquatic (freshwater) | Temperate to warm; seasonal climate | Algae of the family Zygnemataceae | Extant Spirogyra; Ovoidites may be derived from a similar genus |

### Bryophyta

| Genus | Species | Location | Member | Material | Ecogroup | Palaeoclimate requirements | Notes | Images |
| Antulsporites | A. saevus | Cañadon Lahuincó Cañadón Caracoles | Las Chacritas Member | Spores | Upland and Riverside | Can withstand long periods of drought; seasonal climate | Affinities with the family Sphagnaceae in the Sphagnopsida. "Peat moss" spores, related to genera such as Sphagnum that can store large amounts of water. | Extant Sphagnum specimens; Stereisporites, Sculptisporis and Rogalskaisporites probably come from similar genera |
| Neoraistrickia | N. cf. suratensis | Cañadon Lahuincó Cañadón Caracoles | Las Chacritas Member | Spores | Upland and Lowland | Warm to temperate, relatively wet | Affinities with the family Selaginellaceae and Lycopodiaceae in the Lycopsida. | |
| Nevesisporites | N. vallatus N. cf. undatus N. cf. radiatus | Cañadon Lahuincó Cañadón Caracoles | Las Chacritas Member | Spores | Upland and Riverside | Can withstand long periods of drought; seasonal climate | Affinities with Bryophyta. | |
| Retitriletes | R. austroclavatidites R. semimuris R. sp. 1 | Cañadon Lahuincó Cañadón Caracoles | Las Chacritas Member | Spores | Upland and Lowland | Warm to temperate, relatively wet | Affinities with Bryophyta. | |
| Stereisporites | S. sp. cf. S. psilatus | Cañadon Lahuincó Cañadón Caracoles | Las Chacritas Member | Spores | Upland and Riverside | Can withstand long periods of drought; seasonal climate | Affinities with the family Sphagnaceae in the Sphagnopsida. | |

### Equisetales

| Genus | Species | Location | Member | Material | Ecogroup | Palaeoclimate requirements | Notes | Images |
| Equisetites | E. approximatus E. spp. | Cañadon Asfalto Cañadon Lahuincó Paso de Indios Pomelo locality | Las Chacritas Member | Stems | Lowland and Riverside | Warm to temperate, relatively wet | Plants of the group Equisetales. Usually linked with riversides | Equisetites specimen |

### Pteridophyta

| Genus | Species | Location | Member | Material | Ecogroup | Palaeoclimate requirements | Notes | Images |
| Baculatisporites | B. comaumensis | Cañadon Lahuincó | Las Chacritas Member | Spores | Lowland and Riverside | Warm to temperate, relatively wet | Affinities with the family Osmundaceae in the Polypodiopsida. Near fluvial current ferns, related to the modern Osmunda regalis. | Extant Osmunda specimens; Baculatisporites probably come from similar genera or maybe a species from the genus |
| Biretisporites | B. sp. A | Cañadon Lahuincó Cañadón Caracoles | Las Chacritas Member | Spores | Lowland and Riverside | Warm to temperate, relatively wet | Affinities with the Marattiaceae in the Polypodiopsida. Fern spores from low herbaceous flora. | Extant Marattia specimens; Marattisporites probably comes from similar genera |
| Cadargasporites | C. sp. cf. C. reticulatus | Cañadon Lahuincó Cañadón Caracoles | Las Chacritas Member | Spores | Lowland and Riverside | Warm to temperate, relatively wet | Uncertain affinity Fern Spores Filicopsida incertae sedis | |
| Cladophlebis | C. grahami C. oblonga | Cañadon Asfalto Cañadon Lahuincó Paso de Indios Pomelo locality | Las Chacritas Member | Isolated Pinnae | Lowland and Riverside | Warm to temperate, relatively wet | Plants of the family Osmundaceae. | |
| Clavatisporites | C. spp. | Cañadon Lahuincó Cañadón Caracoles | Las Chacritas Member | Spores | Lowland and Riverside | Warm to temperate, relatively wet | Filicopsida incertae sedis | |
| Deltoidospora | D. australis D. minor | Cañadon Lahuincó | Las Chacritas Member | Spores | Upland, Lowland and Riverside | Warm to temperate, relatively wet | Affinities with the families Cyatheaceae/Dicksoniaceae Dipteridaceae/Matoniaceae in the Polypodiopsida. | |
| Dictyophyllidites | D. harrisii | Cañadon Lahuincó Cañadón Caracoles | Las Chacritas Member | Spores | Lowland and Riverside | Warm to temperate, relatively wet | Affinities with the families Cyatheaceae/Dicksoniaceae Dipteridaceae/Matoniaceae in the Polypodiopsida. | |
| Gleichenites | G. cf.taquetrensis | Paso de Indios | Las Chacritas Member | Isolated Pinnae | Lowland and Riverside | Warm to temperate, relatively wet | Plants of the family Gleicheniales. | |
| Ischyosporites | I. marburgensis | Cañadon Lahuincó Cañadón Caracoles | Las Chacritas Member | Spores | Upland, Lowland Riverside | Warm to temperate, relatively wet | Affinities with the family Lygodiaceae and Schizaeaceae in the Polypodiopsida. Climbing or herbaceous fern spores. | Extant Lygodium; Lygodioisporites probably comes from similar genera or maybe a species from the genus |
| Klukisporites | K. lacunus K. variegatus K. sp. cf. K. scaberis | Cañadon Lahuincó Cañadón Caracoles | Las Chacritas Member | Spores | Upland, Lowland Riverside | Warm to temperate, relatively wet | Affinities with the family Lygodiaceae and Schizaeaceae in the Polypodiopsida. Climbing or herbaceous fern spores. | Extant Lygodium; Lygodioisporites probably comes from similar genera or maybe a species from the genus |
| Obtusisporis | O. modestus | Cañadon Lahuincó Cañadón Caracoles | Las Chacritas Member | Spores | Lowland and Riverside | Warm to temperate, relatively wet | Filicopsida incertae sedis | |
| Rugulatisporites | R. sp. | Cañadon Lahuincó | Las Chacritas Member | Spores | Lowland and Riverside | Warm to temperate, relatively wet | Affinities with the family Osmundaceae in the Polypodiopsida. | |
| Sphenopteris | S. patagonica S. hallei | Cañadon Asfalto Cañadon Lahuincó | Las Chacritas Member | Isolated Pinnae | Upland, Lowland and Riverside | Warm to temperate, relatively wet | Plants of the group Sphenopteridae, whose affinity for mesozoic specimens is uncertain, yet has been suggested to be fronds of Dicksoniaceae affinity | |
| Todisporites | T. minor | Cañadon Lahuincó | Las Chacritas Member | Spores | Upland | Warm to temperate, relatively wet. Can withstand long periods of drought; seasonal climate | Affinities with the family Osmundaceae in the Polypodiopsida. | |
| Trilobosporites | T. sp. | Cañadon Lahuincó | Las Chacritas Member | Spores | Upland, Lowland and Riverside | Warm to temperate, relatively wet | Affinities with the families Cyatheaceae/Dicksoniaceae Dipteridaceae/Matoniaceae in the Polypodiopsida. | |
| Verrucosisporites | V. varians | Cañadon Lahuincó | Las Chacritas Member | Spores | Upland | Can withstand long periods of drought; seasonal climate | Affinities with the family Osmundaceae in the Polypodiopsida. | |

### Peltaspermales

| Genus | Species | Location | Member | Material | Ecogroup | Palaeoclimate requirements | Notes |
| Alisporites | A. similis A. lowoodensis A. spp. | Cañadon Lahuincó Cañadón Caracoles Cerro Bandera | Las Chacritas Member Puesto Almada Member | Pollen | Riverside | Warm, can withstand long periods of drought; seasonal climate | Affinities with the families Peltaspermaceae, Corystospermaceae or Umkomasiaceae in the Peltaspermales. Pollen of uncertain provenance that can be derived from any of the members of the Peltaspermales. |
| Antevsia | A. sp. | Pomelo locality | Las Chacritas Member | Pollen-bearing organs | Lowland and Riverside | Warm, can withstand long periods of drought; seasonal climate | Plants of the group Peltaspermaceae. |
| Archangelskya | A. furcata | Cañadon Asfalto Cañadon Lahuincó | Las Chacritas Member | Isolated Pinnae | Lowland and Riverside | Warm, can withstand long periods of drought; seasonal climate | Plants of the group Pteridospermata |
| Lepidopteris | L. scassoi | Pomelo locality A12 locality | Las Chacritas Member | Isolated Pinnae | Lowland and Riverside | Warm, can withstand long periods of drought; seasonal climate | Plants of the group Peltaspermaceae. This species represents the youngest record of the genus, by more than 20 Myr. |
| Peltaspermum | P. sp. | Pomelo locality A12 locality | Las Chacritas Member | Ovuliferous Cones | Lowland and Riverside | Warm, can withstand long periods of drought; seasonal climate | Plants of the group Peltaspermaceae. |
| Vitreisporites | V. pallidus | Cañadon Lahuincó | Las Chacritas Member | Pollen | Riverside | Warm, relatively wet | From the family Caytoniaceae in the Caytoniales. Caytoniaceae are a complex group of Mesozoic fossil floras that may be related to both Peltaspermales and Ginkgoaceae. |

### Cycadeoidopsida

| Genus | Species | Location | Member | Material | Ecogroup | Palaeoclimate requirements | Notes | Images |
| Zamites | Z. sp. | Pomelo locality A12 locality | Las Chacritas Member | Leaflets | Lowland and Riverside | Warm to temperate, can withstand long periods of drought; seasonal climate | Affinities with Bennettitales inside Cycadeoidopsida. | |

### Czekanowskiales

| Genus | Species | Location | Member | Material | Ecogroup | Palaeoclimate requirements | Notes | Images |
| Phoenicopsis | P. sp. | Cañadon Asfalto Pomelo locality | Las Chacritas Member | Pollen Organs | Lowland and Riverside | Warm to temperate, can withstand long periods of drought; seasonal climate | Plants of the group Leptostrobales (Czekanowskiales). Gingko-like taxa | |

### Gnetopsida

| Genus | Species | Location | Member | Material | Ecogroup | Palaeoclimate requirements | Notes | Images |
| Ephedripites | E. spp. | Cañadon Lahuincó Cerro Bandera | Las Chacritas Member Puesto Almada Member | Pollen | Lowland and Riverside | Warm to temperate, can withstand long periods of drought; seasonal climate | A Pollen Grain, affinities with Ephedraceae inside Gnetopsida. | Extant Ephedra, typical example of Ephedraceae. Equisetosporites probably come from a similar or a related Plant |

### Coniferophyta

| Genus | Species | Location | Member | Material | Ecogroup | Palaeoclimate requirements | Notes | Images |
| Agathoxylon | A. spp. | Cañadon Bagual | Las Chacritas Member | Fossil Wood | Upland, Lowland and Riverside | ?Warm to temperate, relatively wet | Affinities with the family Araucariaceae in the Pinales. | |
| Araucariacites | A. australis A. fissus A. pergranulatus A. cf. A. pergranulatus A. sp. A | Cañadon Lahuincó Cañadón Caracoles Cerro Bandera | Las Chacritas Member Puesto Almada Member | Pollen | Upland, Lowland and Riverside | ?Warm to temperate, relatively wet | Affinities with the family Araucariaceae in the Pinales. Conifer pollen from medium to large arboreal plants. | |
| Araucaritites | A. chuchensis A. spp. | Cañadon Asfalto Pomelo locality A12 locality Cañadon Lahuincó Estancia La Vistosa Paso de Indios | Las Chacritas Member | Ovuliferous scales | Upland, Lowland and Riverside | ?Warm to temperate, relatively wet | Plants of the family Araucariaceae. | |
| Athrotaxites | A. ungeri | Cañadon Asfalto Cañadon Lahuincó | Las Chacritas Member | Branched shoots | Upland | ?Warm to temperate, relatively wet | Plants of the family Taxodiaceae | |
| Austrohamia | A. asfaltensis | Cañadon Lahuincó | Las Chacritas Member | Branched shoots & Ovuliferous cones | Upland, Lowland and Riverside | ?Warm to temperate, relatively wet | Plants of the family Cunninghamioideae. Along with the also Argentinian species A. minuta, this specimens represent the oldest fossil taxa that can be confidently assigned to Cupressaceae sensu lato | |
| Brachyoxylon | B. currumilii | Pomelo locality | Las Chacritas Member | Fossil Wood | Upland, Lowland and Riverside | ?Warm to temperate, relatively wet | Plants of the family Araucariaceae or Cheirolepidiaceae | |
| Brachyphyllum | B. cf. lotenaense B. spp. | Cañadon Asfalto Cerro Caracoles Las Chacritas Pomelo locality A12 locality Cañadon Lahuincó Paso de Indios Canela locality | Las Chacritas Member | Branched shoots & Ovuliferous cones | Upland, Lowland and Riverside | ?Warm to temperate, relatively wet | Plants of the family Araucariaceae or Cheirolepidiaceae | |
| Callialasporites | C. dampieri C. microvelatus C. turbatus C. minus C. sp. 1 | Cañadon Lahuincó Cañadón Caracoles Cerro Bandera | Las Chacritas Member Puesto Almada Member | Pollen | Upland, Lowland and Riverside | ?Warm to temperate, relatively wet | Affinities with the family Araucariaceae in the Pinales. Conifer pollen from medium to large arboreal plants. | |
| Cerebropollenites | C. macroverrucosus C. carlylensis C. mesozoicus C. sp. 1 | Cañadon Lahuincó Cañadón Caracoles Cerro Bandera | Las Chacritas Member Puesto Almada Member | Pollen | Upland, Lowland and Riverside | ?Warm to temperate, relatively wet | Affinities with both Sciadopityaceae and Miroviaceae in the Pinopsida. This pollen's resemblance to extant Sciadopitys suggest that Miroviaceae may be an extinct lineage of Sciadopityaceae-like plants. | Extant Sciadopitys. Cerebropollenites likely come from a related plant |
| Classopollis | C. classoides C. intrareticulatus C. simplex C. itunensis C. torosus | Cañadon Lahuincó Cañadón Caracoles Cerro Bandera | Las Chacritas Member Puesto Almada Member | Pollen | Lowland and Coastal lake | Warm to temperate, can withstand long periods of drought; seasonal climate | Affinities with the Hirmeriellaceae in the Pinopsida. Classopollis is the most abundant component of the assemblage, with ranges from 73 to 81.6% to 89.6%-89.7% in some samples. | |
| Elatoclaudus | E. confertus E. jabalpurensis | Cañadon Asfalto Cañadon Lahuincó Pomelo locality | Las Chacritas Member | Branched shoots | Upland and Lowland | Warm to temperate, can withstand long periods of drought; seasonal climate | Plants of the family Cupressaceae | |
| Exesipollenites | E. sp. | Cañadon Lahuincó | Las Chacritas Member | Pollen | Lowland and Coastal lake | Warm to temperate, can withstand long periods of drought; seasonal climate | Affinities with the Hirmeriellaceae in the Pinopsida. Classopollis is the most abundant component of the assemblage, with ranges from 73 to 81.6% to 89.6%-89.7% in some samples. | |
| Indusiisporites | I. parvisaccatus I. sp. 1 I. sp. 2 I. sp. 3 | Cañadón Lahuincó Cañadón Caracoles | Las Chacritas Member | Pollen | Upland | Temperate, relatively dry | Affinities with the family Podocarpaceae. Pollen from diverse types of Podocarpaceous conifers, that include morphotypes similar to the low arbustive Microcachrys and the medium arbustive Lepidothamnus, likely linked with Upland settings | |
| Inaperturopollenites | I. indicus I. giganteus I. microgranulatus I. cf. reidi I. sp. 1 I. sp. 2 | Cañadon Lahuincó | Las Chacritas Member | Pollen | Upland, Lowland and Riverside | ?Warm to temperate, relatively wet | Affinities with the family Araucariaceae in the Pinales. Conifer pollen from medium to large arboreal plants. | |
| Kaokoxylon | K. spp. | Cañadon Bagual | Las Chacritas Member | Fossil Wood | Upland, Lowland and Riverside | ?Warm to temperate, relatively wet | Affinities with the family Araucariaceae in the Pinales. Represents the youngest record of the genus, otherwise know from Permain or Triassic strata. | |
| Microcachryidites | M. castellanosii M. antarcticus | Cañadón Lahuincó Cañadón Caracoles Cerro Bandera | Las Chacritas Member Puesto Almada Member | Pollen | Upland | Temperate, relatively dry | Affinities with the family Podocarpaceae. Pollen from Podocarpaceous conifers similar to the low arbustive Microcachrys | Extant Microcachrys Cone, example of the Podocarpaceae. Microcachryidites is similar to the pollen found on this genus |
| Pagiophyllum | P. divaricatum P. fiestmantelli | Cañadon Asfalto Pomelo locality A12 locality Cañadon Lahuincó Paso de Indios Canela locality | Las Chacritas Member | Branched shoots | Lowland and Coastal lake | Warm to temperate, can withstand long periods of drought; seasonal climate | Plants of the family Araucariaceae or Cheirolepidiaceae | |
| Pelourdea | P. sp. | Cañadon Asfalto | Las Chacritas Member | Pollen Organs | Lowland and Coastal lake | Warm to temperate, can withstand long periods of drought; seasonal climate | Incertae sedis inside Coniferales, suggested as a member of its own family, the "Pelourdeaceae". A hygrophytic riparian conifer with herbaceous or shrubby habit. Some specimens are difficult to identify. | |
| Perinopollenites | P. elatoides | Cañadón Lahuincó | Las Chacritas Member | Pollen | Upland and Lowland | Warm to temperate; seasonal climate | Affinities with the family Cupressaceae in the Pinopsida. Pollen that resembles that of extant genera such as the genus Actinostrobus and Austrocedrus, probably derived from Upland environments. | Extant Austrocedrus. Exesipollenites and Perinopollenites maybe come from a related plant |
| Phrixipollenites | P. sp. | Cañadón Lahuincó | Las Chacritas Member | Pollen | Upland | Temperate, relatively dry | Affinities with the family Podocarpaceae. | |
| Pinuspollenites | P. globosaccus | Cañadon Lahuincó Cañadón Caracoles | Las Chacritas Member | Pollen | Upland, Lowland and Riverside | ?Warm to temperate, relatively wet | Affinities with the family Pinaceae in the Pinopsida. Conifer pollen from medium to large arboreal plants. | |
| Podocarpidites | P. verrucosus P. astrictus P. ellipticus P. multesimus P. variabilis P. sp. cf. P. radiatus P. sp. cf. P. verrucosus P. sp. 1 | Cañadón Lahuincó Cañadón Caracoles | Las Chacritas Member | Pollen | Upland | Temperate, relatively dry | Affinities with the family Podocarpaceae in the Pinopsida. | Extant Podocarpus Cone, example of the Podocarpaceae. Podocarpidites is similar to the pollen found on this genus |
| Podocarpoxylon | P. spp. | Cañadon Bagual | Las Chacritas Member | Fossil Wood | Upland, Lowland and Riverside | ?Warm to temperate, relatively wet | Affinities with the family Podocarpaceae in the Pinopsida. | |
| Podosporites | P. variabilis P. sp. 1 | Cañadón Lahuincó Cañadón Caracoles | Las Chacritas Member | Pollen | Upland | Temperate, relatively dry | Affinities with the family Podocarpaceae in the Pinopsida. | |
| Protocupressinoxylon | P. spp. | Cañadon Bagual | Las Chacritas Member | Fossil Wood | Upland, Lowland and Riverside | ?Warm to temperate, relatively wet | Affinities with the family Hirmeriellaceae in the Pinopsida. | |
| Prototaxoxylon | P. spp. | Cañadon Bagual | Las Chacritas Member | Fossil Wood | Upland, Lowland and Riverside | ?Warm to temperate, relatively wet | Affinities with the family Taxaceae in the Pinopsida. Alternatively, it can represent woods of the "Mesozoic Prototaxoxylon Group", an unnamed conifer family of possible Permian affinities. | |