Massospondylidae is a

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

of early massopod

dinosaur Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the evolution of dinosaurs is t ...

s that existed in

Asia Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an are ...

Africa Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...

, North America,

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the sout ...

and

Antarctica Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean, it contains the geographic South Pole. Antarctica is the fifth-largest cont ...

Hellert, Spencer M. "A New Basal Sauropodomorph from The Early Jurassic Hanson Formation of Antarctica." Geological Society of America Abstracts with Programs,. Vol. 44. No. 5. 2012. during the

Late Triassic The Late Triassic is the third and final epoch of the Triassic Period in the geologic time scale, spanning the time between Ma and Ma (million years ago). It is preceded by the Middle Triassic Epoch and followed by the Early Jurassic Epoch. ...

to the

Early Jurassic The Early Jurassic Epoch (geology), Epoch (in chronostratigraphy corresponding to the Lower Jurassic series (stratigraphy), Series) is the earliest of three epochs of the Jurassic Period. The Early Jurassic starts immediately after the Triassic-J ...

periods. Several dinosaurs have been classified as massospondylids over the years. The largest

cladistic Cladistics (; ) is an approach to biological classification in which organisms are categorized in groups ("clades") based on hypotheses of most recent common ancestry. The evidence for hypothesized relationships is typically shared derived char ...

analysis of early sauropodomorphs, which was presented by Apaldetti and colleagues in November 2011, found '' Adeopapposaurus'', '' Coloradisaurus'', '' Glacialisaurus'', ''

Massospondylus ''Massospondylus'' ( ; from Greek, (massōn, "longer") and (spondylos, "vertebra")) is a genus of sauropodomorph dinosaur from the Early Jurassic. (Hettangian to Pliensbachian ages, ca. 200–183 million years ago). It was described by S ...

'', '' Leyesaurus'' and ''

Lufengosaurus ''Lufengosaurus'' (, meaning "Lufeng lizard") is a genus of massospondylid dinosaur which lived during the Early Jurassic period in what is now southwestern China. Discovery, taxonomy and research During the late 1930s geologist Bien Meinian ...

'' to be massospondylids. This result supports many previous analyses that tested fewer taxa. However, this analysis found the two recently described North American massopods, ''

Sarahsaurus ''Sarahsaurus'' is a genus of basal sauropodomorph dinosaur which lived during the Early Jurassic period in what is now northeastern Arizona, United States. Discovery and naming All specimens of ''Sarahsaurus'' were collected from the Lower J ...

'' and '' Seitaad'', and the

South Africa South Africa, officially the Republic of South Africa (RSA), is the Southern Africa, southernmost country in Africa. It is bounded to the south by of coastline that stretch along the Atlantic Ocean, South Atlantic and Indian Oceans; to the ...

n '' Ignavusaurus'' to nest outside Massospondylidae, as opposed to some provisional proposals. Earlier in 2011, '' Pradhania'', a sauropodomorph from India, was tested for the first time in a large cladistic analysis and was found to be a relatively basal massospondylid. ''

Mussaurus ''Mussaurus'' (meaning "mouse lizard") is a genus of herbivorous sauropodomorph dinosaur that lived in southern Argentina during the Early Jurassic, with a maximum age of 192.78 ± 0.14 Ma. It receives its name from the small size of the skel ...

'' and '' Xixiposaurus'' may also be included within Massospondylidae. In 2019, a specimen previously assigned to ''Massospondylus'' from South Africa was re-examined and found to belong to a separate genus that was named '' Ngwevu''.

Phylogeny

Massospondylidae, which was first named by Huene in 1914, is a

stem-based taxon Phylogenetic nomenclature is a method of nomenclature for taxa in biology that uses phylogenetic definitions for taxon names as explained below. This contrasts with the traditional approach, in which taxon names are defined by a '' type'', which ...

. It was defined by Sereno as all animals more closely related to ''

Massospondylus carinatus ''Massospondylus'' ( ; from Greek, (massōn, "longer") and (spondylos, "vertebra")) is a genus of sauropodomorph dinosaur from the Early Jurassic. (Hettangian to Pliensbachian ages, ca. 200–183 million years ago). It was described by Si ...

'' than to ''

Plateosaurus engelhardti ''Plateosaurus'' (probably meaning "broad lizard", often mistranslated as "flat lizard") is a genus of plateosaurid dinosaur that lived during the Late Triassic period, around 214 to 204 million years ago, in what is now Central and Northern Euro ...

'' and ''

Saltasaurus loricatus ''Saltasaurus'' (which means "lizard from Salta") is a genus of saltasaurid dinosaur of the Late Cretaceous period of Argentina. Small among sauropods, though still heavy by the standards of modern creatures, ''Saltasaurus'' was characterized by ...

''. The following simplified

cladogram A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to ...

is based on an analysis presented by Chapelle and colleagues in 2019. Below is a simplified cladogram after Müller, 2019. The following cladogram shows the position of Massospondylidae within Massopoda, according to Oliver W. M. Rauhut and colleagues, 2020:

References

{{Taxonbar, from=Q250154 Massopoda Norian first appearances Early Jurassic extinctions Prehistoric dinosaur families