Invictibellatrix
From Latin 'invictus' (unconquered) and 'bellatrix' (female warrior), honoring the later role of megaraptorans as apex predators in Gondwana.
Early Cretaceous stages
Invictibellatrix is an extinct genus of megaraptoran theropod dinosaur known from the Early Cretaceous (Barremian age) Wessex Formation of England. The genus contains a single species, Invictibellatrix amberina, known from a single braincase. Invictibellatrix is estimated to have a body mass between 200–300 kg (440–660 lb) and a body length of around 4 m (13 ft).
Diagnosis
- Small basipterygoid recess anterior to the anterior tympanic recess on each side of the parabasisphenoid
- Slightly transversely compressed, hourglass-shaped nuchal crest
- Two large, deep, dorsoventrally elongate paracondylar recesses on the ventrolateral sides of the basioccipital
- Parasagittal nuchal crest recesses that are slightly curved and pronounced
Species
Invictibellatrix amberina Morrison et al., 2026
Type species
Named for the amber in the plant debris beds of the Wessex Formation.
- Holotype
- NHMUK PV R6775 , Natural History Museum
- Material
- Partial braincase, beach-rolled, preserving the basioccipital, exoccipitals, basisphenoid, parasphenoid, opisthotic, prootic and possible laterosphenoid fragments; everything anterior to the laterosphenoids and most of the skull roof is missing.
- Horizon
- Wessex Formation, Barremian, Early Cretaceous , 125.8–121.4 million years ago
- Locality
- Sudmoor Point, Isle of Wight, United Kingdom The exact horizon was not recorded; the lower plant debris beds L1 to L5, which crop out at Sudmoor Point, are the most likely source.
References
- Morrison, C.; Scherer, C. R.; Mannion, P.; Porro, L. B.; Clark, B.; Folkes, D. D.; Barrett, P. M. (2026). A new megaraptoran dinosaur from the Lower Cretaceous Wessex Formation, UK, and its implications for theropod evolution and biogeography. Royal Society Open Science 13(10): 260937. The Royal Society. doi:10.1098/rsos.260937 morrison2026a