Euhelopodidae
Extinct family of dinosaurs
From Wikipedia, the free encyclopedia
Euhelopodidae is a family of sauropod dinosaurs of disputed membership and affinities, which contains Euhelopus and its close relatives. Most proposed euhelopodids are from East Asia.
| Euhelopodids | |
|---|---|
| |
| Life restoration of a Euhelopus zdanskyi | |
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Reptilia |
| Clade: | Dinosauria |
| Clade: | Saurischia |
| Clade: | †Sauropodomorpha |
| Clade: | †Sauropoda |
| Clade: | †Macronaria |
| Clade: | †Somphospondyli |
| Family: | †Euhelopodidae Romer, 1956 |
| Type species | |
| †Euhelopus zdanskyi Wiman, 1929 | |
| Genera | |
| Synonyms | |
| |
Euhelopodidae was first recognized by Carl Wiman in 1929, under the name Helopodidae, as Euhelopus was originally named Helopus.[1] However, the name had already been proposed for a bird, so in 1956 Alfred Sherwood Romer proposed the name Euhelopus and Euhelopodinae as replacements; Romer classified Euhelopodinae as a subfamily of Brachiosauridae, in which he also included Camarasaurinae and Cetiosaurinae, rather than as a family of its own. In addition to Euhelopus itself, Romer included Chiayusaurus, Omeisaurus, and Tienshanosaurus in Euhelopodinae.[2]
The taxonomic content of Euhelopodidae is uncertain, as a result of the unstable position of Euhelopus itself.[3] Some studies have concluded that Euhelopus is a non-neosauropod closely related to Mamenchisaurus, which would make Euhelopodidae equivalent to Mamenchisauridae. Other studies have interpreted Euhelopus as neosauropod united with titanosaurs in Somphospondyli. A joint study by Jeffrey Wilson and Paul Upchurch, who had previously taken opposite sides in the debate, concluded that Euhelopus was closely related to titanosaurs.[4] However, the lack of research on Mamenchisaurus-like taxa has hindered proper testing of this hypothesis, and there are several similarities between Euhelopus and Mamenchisaurus-like taxa that have not been taken into account in most analyses.[5]
Michael D'Emic (2012) formulated the first phylogenetic definition of Euhelopodidae, defining it as the clade containing "neosauropods more closely related to Euhelopus zdanskyi than to Neuquensaurus australis". Below is a cladogram presenting the cladistic hypothesis of Euhelopodidae proposed by D'Emic.
| Euhelopodidae | |
In their 2021 description of Silutitan, Wang et al. recovered it as a derived euhelopodid, as the sister taxon to Euhelopus. The results of their phylogenetic analysis, which included several other euhelopodid taxa, are shown in the cladogram below:[6]
