Olivier Rieppel’s research while affiliated with Field Museum of Natural History and other places

The cleared and stained skeleton of a juvenile Lanthanotus bomeensis provides additional evidence for the "cervicalization" of an anterior dorsal vertebra, resulting in the 9 cervical vertebrae thought to be diagnostic of the Varanidae. Lanthanotus shows two complete sternal ribs associated with the vertebral segments 10 and 11, and an incomplete sternal rib associated with the 9th segment; Varanus shows three complete sternal ribs associated with the vertebral segments 10, 11 and 12. The loss of a sternal rib associated with the 12th segment is autapomorphic for Lanthanotus. Nine cervical vertebrae may be diagnostic for the genus Varanus only, since Lanthanotus preserves a rudimentary sternal rib associated with the 9th vertebral segment, at least at some stage of its ontogeny. A free carpal "intermedium" is absent (or variably present) in Lanthanotus. The pattern of epiphyseal calcification in the carpus and tarsus of Lanthanotus is described and compared to Varanus.