The Sarmiento Formation (Spanish: Formación Sarmiento), in older literature described as the Casamayor Formation, is a geological formation in Chubut Province, Argentina, in central Patagonia, which spans around 30 million years from the mid-Eocene to the early Miocene. It predominantly consists of pyroclastic deposits, which were deposited in a semi-arid environment. It is divided up into a number of members. The diverse fauna of the Sarmiento Formation, including a variety of birds, crocodilians, turtles and snakes, also includes many mammals such as South American native ungulates (notoungulates, litopterns, astrapotheres) as well as armadillos, and caviomorph rodents. Material was copied from this source, which is available under a Creative Commons Attribution 3.0 International License Some trace fossils have also been found, such as Teisseirei.
Paleofauna Amphibians Name Species Member/Locality Material Notes ImageAnura indet.Currently undescribedUpper Puesto Almendra MemberCalyptocephalellaC. canqueliUpper Puesto Almendra MemberA calyptocephalellid frogEupsophusE. sp.Upper Puesto Almendra MemberAn alsodid frogNeoprocoelaN. edentatusUpper Puesto Almendra MemberA leptodactylid frog
Birds Name Species Member/Locality Material Notes ImageAndrewsornisA. abottiUpper Puesto Almendra MemberA phorusrhacidLoxornisL. clivusUpper Puesto Almendra MemberPhysornisP. sp.Upper Puesto Almendra MemberA phorusrhacidTelmabatesT. antiquusUpper Puesto Almendra MemberA presbyornithid
Reptiles Crocodylomorphs Name Species Member/Locality Material Notes ImageEocaimanE. cavernensisGran Barranca MemberA caimanSebecus S. icaeorhinusGran Barranca Member Disarticulated skull, mandible, and some postcranial material.A sebecid notosuchian.
Lepidosaurs Name Species Member/Locality Material Notes ImageChubutophisC. grandisGran Barranca MemberA boa snakeGaimanophisG. tenuisTrelew MemberA boa snakeIguanidae indet.Currently undescribedUpper Puesto Almendra MemberMadtsoiaM. bai M. sp.Gran Barranca and Upper Puesto Almendra MembersA madtsoiid snakeWaincophisW. australisGran Barranca MemberA boa snake
Testudines Name Species Member Material Notes ImageChelonoidisC. gringorumTrelew MemberA tortoiseGaffneylaniaG. auricularisA meiolaniid stem-turtleNiolamiaN. argentinaGran Barranca MemberTestudininae indet.Currently undescribed Puesto Almendra Member A tortoise
Mammals
Meridiolestidans Name Species Member/Locality Material Notes ImageNecrolestes N. mirabilisColhué Huapí MemberYoungest known meridiolestidan
Meridiungulates Name Species Member/Locality Material Notes ImageAcoelodusA proclivusGran Barranca MemberA notoungulate of uncertain affinities.AcoelohyraxA. sigma A. complicatissimusGran Barranca MemberA notohippid notoungulate Adiantoides A. magnus Gran Barranca MemberAn indaleciid litoptern AlbertogaudryaA. carahuasensis A. unicaGran Barranca MemberAn astrapothere Amilnedwardsia A. breviculaGran Barranca MemberAncylocoelusA. frequensPuesto Almendra MemberA leontiniid notoungulate Anisolambda A. amel A. fissidensGran Barranca MemberA proterotheriid litopternAnisotemnusA. distentusGran Barranca and Vera MembersAn isotemnid notoungulateAntepithecus A. brachystephanus A. innexusGran Barranca and Rosado MembersA notopithecid notoungulateArchaeohyraxA. patagonicusGran Barranca and Puesto Almendra MembersA archaeohyracid notoungulateArchaeophylusA. patriusPuesto Almendra MemberA interatheriid notoungulate Archaeopithecus A. rogeriGran Barranca MemberA archaeopithecid notoungulateArchaeotypotheriumA. propheticusPuesto Almendra and Vera Members An archaeohyracid notoungulate ArgyrohippusA. boulei A. fraterculus
A. praecoxColhué Huapí and Puesto Almendra Members ArgyrohyraxA. proavusPuesto Almendra MemberAsmodeusA. osborniPuesto Almendra MemberAstraponotus A. assymmetrus A. dicksoni
A. dilatatus
A. holdichi
A. thompsoniGran Barranca Member Astrapotherium A. ruderariumColhué Huapí member Astrapotheriidae indet.Currently undescribedColhué Huapí MemberBryanpattersoniaB. sulcidensPuesto Almendra and Vera MembersGenus probably a synonym of ArchaeotypotheriumCochiliusC. brevirostris C. fumensis
C. volvensColhué Huapí and Puesto Almendra Members Colpodon C. distinctus C. propinquus
C. sp.Colhué Huapí MemberA leontiniid.ConiopterniumC. andinumPuesto Almendra MemberA macraucheniid litopternCramaucheniaC. normalisColhué Huapí and Puesto Almendra Members Nearly complete skull and humerusA macraucheniid litopternCramaucheniinae indet.Currently undescribedPuesto Almendra MemberDeuterotheriumD. distichumPuesto Almendra Member Didolodus D. multicuspsis D. magnus D. minor D. latigonusGran Barranca and Rosado MembersAll species mostly known from dental remainsA didolodontid.EdvardotrouessartiaE. solaGran Barranca MemberEohyrax E. isotemnoides E. platyodus
E. praerusticusGran Barranca and Rosado MembersEolicaphriumE. primariumGran Barranca MemberA litoptern EomorphippusE. bondi E. neilopdykei
E. obscurusRosado and Lower Puesto Almendra membersA notohippid notoungulate Eopachyrucos E. pliciformis E. pliciferus Rosado and Puesto Almendra MembersMandibular and skull remainsAn interatheriid. Ernestohaeckelia E. aculeata E. acutidensGran Barranca MemberA litopternErnestokokeniaE. nitida E. patagonicaGran Barranca MemberMostly known from dental remainsA didolodontid.EurygeniumE. latirostrisPuesto Almendra MemberA notohippid notoungulate GuilielmofloweriaG. plicataGran Barranca MemberA proterotheriid.GuilielmoscottiaG. pliciferaRosado and Vera MembersA interatheriid notoungulateHegetotheriopsis H. sulcatusTrelew Member Hegetotherium H. novumTrelew MemberA hegetotheriid notoungulate HomalostylopsH. atavus H. parvusGran Barranca and Rosado MembersA notostylopid notoungulateHenricofilholiaH. lustrata H. cingulata
H. circumdata
H. intercincta
H. vucetichiaUpper Puesto Almendra MemberAn astrapothereHenricosbornia H. ampla H. lophodonta
H. minutaGran Barranca MemberInteratheriumI. sp.Colhué Huapí MemberAn interatheriidIsotemnusIsotemnus ctalego Isotemnus haugi
Isotemnus latidens
Isotemnus primitivusGran Barranca MemberIsotemnidae indet.Currently undescribedPuesto Almendra MemberLambdaconusL. lacerumColhué Huapí MemberLeontiniaL. gaudryi L. sp.Puesto Almendra MemberMaddeniaM. lapidariaPuesto Almendra MemberMaxschlosseriaM. consumata M. expansa
M. minima
M. minuta
M. praeterita
M. rusticula
M. septaGran Barranca MemberAn oldfieldthomasiid notoungulataMedistylusM. dorsatusPuesto Almendra MemberMorphippus M. complicatus M. fraternus
M. hypselodus
M. imbricatus
M. quadrilobusPuesto Almendra MemberNotopithecusN. adapinusGran Barranca and Rosado MembersNotostylopsN. murinus N. appressus
N. pendens
N. pigafettai
N. sp.Gran Barranca and Rosado MembersOldfieldthomasiaO. anfractuosa O. debilitata
O. parvidens
O. transversaGran Barranca MemberOthnielmarshia O. curviristra O. lacunifera
O. reflexaGran Barranca MemberPachyrukhosP. sp.Colhué Huapí MemberPaginulaP. parcaGran Barranca MemberParamacraucheniaP. scamnata P. inexspectataColhué Huapí MemberParastrapotheriumP. cingulatum P. ephebicum
P. holmbergi
P. lemoinei
P. trouessarti
P. sp.Colhué Huapí and Puesto Almendra MembersPatagonhippusP. canterensis P. dukeiPuesto Almendra MemberA notohippid notoungulatePaulogervaisiaP. inustaGran Barranca and Rosado MembersPeripantostylopsP. minutusGran Barranca MemberPeriphragnisP. exauctus P. sp.Rosado MemberPleurostylodonP. complanatus P. crassiramis
P. modicusGran Barranca MemberAn isotemnid notoungulatePolymorphisP. lecheiGran Barranca MemberA macraucheniid litopternProadiantusP. excavatusPuesto Almendra MemberProadinotheriumP. leptognathusPuesto Almendra MemberA toxodontid notoungulateProargyrohyraxP. curanderensis P. sp.Vera MemberAn interatheriid notoungulateProectocion P. argentinus P. precisusGran Barranca MemberAn adianthid litopternProgaleopithecusP. fissurellatus P. tournoueri
P. sp.Puesto Almendra MemberA interatheriid notoungulateProhegetotheriumP. sculptum P. sp.Puesto Almendra MemberProheptaconusP. patagonicusColhué Huapí and Trelew MembersAn adianthid litopternProlicaphriumP. spectabile P. specillatumColhué Huapí MemberA proterotheriid litopternPropachyrucosP. smithwoodwardiPuesto Almendra MemberPropyrotheriumP. saxeumGran Barranca MemberProsotheriumP. garzoniPuesto Almendra MemberProtarchaeohyraxP. minorPuesto Almendra MemberA archaeohyracid notoungulateProterotheriidae indet.Currently undescribedPuesto Almendra MemberProtheosodonP. coniferusPuesto Almendra MemberProtypotheriumP. sp.Colhué Huapí MemberPseudhyraxP. eutrachytheroidesPuesto Almendra MemberPternoconiusP. polymorphoides P. tournoueri
P. bondiColhué Huapí and Puesto Almendra MembersPueliaP. sigma P. coarctatusGran Barranca, Rosado, and Vera MembersA notohippid notoungulatePyrotheriumP. romeroiPuesto Almendra MemberRhynchippusR. pumilus R. equinus
R. sp.Puesto Almendra MemberRosendoR. pascualiVera MemberA notohippid notoungulateRutimeyeriaR. conuliferaGran Barranca MemberA litopternSantiagorothiaS. chiliensisVera MemberScagliaS. kraglievichorumGran Barranca MemberScarrittiaS. canquelensis S. barranquensisPuesto Almendra MemberSparnotheriodonS. epsilonoidesGran Barranca MemberTeratopithecusT. elpidophorosGran Barranca MemberTetragonostylopsT. apthomasiGran Barranca MemberTetramerorhinusT. sp.Colhué Huapí MemberTeushentheriumT. camaronensisPuesto Almendra MemberTheosodonT.? frenguelliiColhué Huapí MemberThomashuxleyaT. rostrata Gran Barranca MemberAn isotemnid notoungulateTrachytherusT. spegazzinianus T. sp.Puesto Almendra MemberTranspithecusT. obtentus T. sp.Gran Barranca and Rosado MembersTricoelodusT. bicuspidatusPuesto Almendra MemberAn adianthid litopternTrigonolophodonT. elegans T. inflatusPuesto Almendra MemberA homalodotheriid notoungulateTrigonostylopsT. wortmani T. sp.Gran Barranca MemberAn astrapothereUltrapithecusU. rutilansGran Barranca and Rosado MembersVictorlemoineaV. labyrinthica V. emarginata
V. longidens
V. sp.Gran Barranca Member
Xenarthrans Name Species Member/Locality Material Notes ImageArchaeutatusA. malaspinensis A. sp.Upper Puesto Almendra MemberAstegotheriumA. dichotomumGran Barranca MemberBarrancatatusB. rigidus B. maddeni
B. sp.Vera and Upper Puesto Almendra MembersClypeotheriumC. magnumUpper Puesto Almendra MembersCochlopsC. sp.Colhué Huapí MemberGlyptodontinae indet.Currently undescribedColhué Huapí and Upper Puesto Almendra MembersHapaloides H. ignavus H. laeviusculus
H. ponderosus
H. sp.Colhué Huapí MemberHolomegalonyxH. menendeziColhué Huapí MemberMachlydotheriumM. ater M. sparsum
M. sp.Gran Barranca, Rosado, Upper Puesto Almendra, and Vera MembersMazzoniphractusM. ingensRosado MemberMegalonychidae indet.Currently undescribedColhué Huapí MemberMeteutatusM. anthinus M. ascendens
M. concavus
M. confluens
M. lagenaformis
M. lucidus
M. minutus
M. nepotulus
M. percarinatus
M. tortuosus
M. sp.Gran Barranca, Rosado, Upper Puesto Almendra, and Vera MembersNematheriumN. sp.Colhué Huapí MemberOctodontotheriumO. grande O. crassidensUpper Puesto Almendra MemberPalaeopeltisP. inornatusUpper Puesto Almendra MemberParutaetusP. chicoensis P. chilensis
P. clusus
P. signatusGran Barranca, Rosado, Upper Puesto Almendra, and Vera MembersPeltephilusP. pumilus P. undulatus
P. sp. Colhué Huapí and Upper Puesto Almendra MembersPeltephilidae indet.Currently undescribedColhué Huapí, Rosado, Upper Puesto Almendra, and Vera MembersProeuphractusP. setigerUpper Puesto Almendra MemberProeutatusP. oenophorum Proeutatus robustus
P. sp.Colhué Huapí MemberPropalaehoplophorusP sp.Colhué Huapí MemberProplatyarthrusP longipesVera MemberProschismotheriumP. oppositum P. sp.Colhué Huapí MemberProstegotheriumP. astrifer P. notostylopianum
P. sp.Gran Barranca MemberProzaedyusP. humilis P. impressus
P. planus