Open Paleo

Majungasaurinae

Tortosa et al., 2014 Type genus Majungasaurus

Its genera lived 83.6–66.0 million years ago Late Cretaceous
Late Cretaceous stages

Majungasaurinae is a subfamily of abelisaurid theropods, one of the two main branches of the family Abelisauridae, and is defined as all abelisaurids more closely related to Majungasaurus than to Carnotaurus. It represents a largely Indo-Madagascan radiation of the Late Cretaceous whose members include Majungasaurus, Rajasaurus, Indosaurus, and Rahiolisaurus, alongside European forms such as Arcovenator. These were mid-sized, bipedal predators with tall, deep skulls and powerful jaws but greatly reduced, immobile forearms; their stout legs suited striding rather than fast running, and they are thought to have preyed mainly on the large sauropods they lived among. The group is set apart from its sister branch, the carnotaurines, chiefly by features of the frontal bones and braincase. Its ancestors originated in Gondwana and became distinct from their South American relatives as the southern landmasses broke apart.

Under dispute

The validity and rank of Majungasaurinae are contested. Most analyses since Tortosa and colleagues (2014) recover and use the subfamily for the Indo-Madagascan abelisaurids, but Pol and colleagues (2024) recovered Abelisaurus within this clade and argued that Majungasaurinae would therefore become a junior synonym of the nominotypical subfamily Abelisaurinae — the subfamily automatically based on Abelisaurus, type genus of Abelisauridae (Bonaparte and Novas, 1985). That result rests on the unstable position of Abelisaurus and has not been broadly adopted, so the clade is retained under its prevailing name.

Diagnosis

  1. Single median frontal horn or dome (rather than paired cornual structures)
  2. Thickened frontals with a distinct nuchal crest
  3. Reduced supratemporal fossa on the frontal
  4. Fusion of the frontals in mature individuals

Genera placed directly in Majungasaurinae

  • Arcovenator Tortosa et al., 2014 Campanian (83.6–72.2 Ma)Franceunder dispute
  • Indosaurus Disputed Huene & Matley, 1933 Maastrichtian (72.2–66.0 Ma)India
  • Majungasaurus Lavocat, 1955 Maastrichtian (72.2–66.0 Ma)Madagascar
  • Rahiolisaurus Novas et al., 2010 Maastrichtian (72.2–66.0 Ma)Indiaunder dispute
  • Rajasaurus Wilson et al., 2003 Maastrichtian (72.2–66.0 Ma)India

References

  1. Tortosa, T.; Buffetaut, E.; Vialle, N.; Dutour, Y.; Turini, E.; Cheylan, G. (2014). A new abelisaurid dinosaur from the Late Cretaceous of southern France: Palaeobiogeographical implications. Annales de Paléontologie 100(1): 63-86. Elsevier BV. doi:10.1016/j.annpal.2013.10.003

    Named Arcovenator and erected the subfamily Majungasaurinae.

    tortosa2014a
  2. Bonaparte, J. F.; Novas, F. E. (1985). Abelisaurus comahuensis, n.g., n.sp., Carnosauria del Crétacico Tardio de Patagonia [Abelisaurus comahuensis, n.g., n.sp., Carnosauria from the Late Cretaceous of Patagonia]. Ameghiniana 21: 259-265.

    Erected the family Abelisauridae for type genus Abelisaurus comahuensis; the nominotypical subfamily Abelisaurinae derives from it automatically (ICZN Art. 37), with the same authorship.

    bonaparte1985b
  3. Pol, D.; Baiano, M. A.; Černý, D.; Novas, F. E.; Cerda, I. A.; Pittman, M. (2024). A new abelisaurid dinosaur from the end Cretaceous of Patagonia and evolutionary rates among the Ceratosauria. Cladistics 40(3): 307-356. Wiley. doi:10.1111/cla.12583

    Recovered Abelisaurus within Majungasaurinae and argued the subfamily is a junior synonym of Abelisaurinae.

    pol2024a