Kingdom Animalia Infraclass Archosauromorpha Scientific name Hallopus victor Rank Genus | Class Sauropsida Superorder Crocodylomorpha Phylum Chordata | |
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Family Hallopodidae Marsh, 1881 Similar Litargosuchus, Sphenosuchus, Trialestes, Junggarsuchus, Saltoposuchus | ||
Hallopus was a prehistoric reptile, classified by O. C. Marsh in 1881 as a dinosaur. It was a quite small animal, reaching a length of 1 m (3.3 ft). It was redescribed as a sphenosuchian crocodylomorph. Later, it was speculated to be more derived than Sphenosuchus and near or within the Junggarsuchus + Crocodyliformes node [1].
In redescribing the Morrison Formation "sphenosuchian" Macelognathus, Göhlich et al. (2005) recognized several anatomical similarities between Macelognathus and Hallopus while also noting if the provenance of the latter was correct, they would overlap stratigraphically.
A recent phylogenetic analysis recovered Hallopus in a clade with Macelognathus and Almadasuchus, the Hallopodidae (defined as "all taxa more closely related to Hallopus victor than to Protosuchus richardsoni or Dibothrosuchus elaphros). The Hallopodidae was recovered as the nearest sister to the Crocodyliformes and more derived than Junggarsuchus or the "sphenosuchians" whose monophyly was not supported in this analysis.