Iani

Iani (after Ianus) is an extinct genus of rhabdodontomorph iguanodontian dinosaur from the Late Cretaceous Cedar Mountain Formation of Utah, United States. The genus contains a single species, I. smithi, known from a partial skeleton including the skull. Its discovery serves as a link between the genus Tenontosaurus and the Rhabdodontidae, with both along with Iani being members of the clade Rhabdodontomorpha.

Discovery and naming
The Iani holotype specimen, NCSM 29373, was discovered in 2014 in sediments of the Cedar Mountain Formation (lower Mussentuchit Member) in Emery County, Utah, United States. The specimen consists of a partial skeleton including a nearly complete, disarticulated skull, cervical, dorsal, sacral, and caudal vertebrae, ribs and haemal arches, partial pectoral and pelvic girdles, and the right arm and leg.

In 2023, Zanno et al. described Iani smithi as a new genus and species of rhabdodontomorph iguanodontian based on these fossil remains. The generic name, "Iani", alludes to Ianus, the Roman god of transitions, referencing the changing biota of the time. The specific name, "smithi", honors Joshua Aaron Smith and his paleontological contributions.

Classification
Zanno et al. (2023) recovered Iani as a basal rhabdodontomorph member of the Iguanodontia. They interpreted it as a transitional taxon between Tenontosaurus and other Late Cretaceous rhabdodontomorphs (the Rhabdodontidae). The cladograms below display the results of their phylogenetic analyses using different datasets:

Topology 1: Poole (2022) dataset

Topology 2: Dieudonné et al. (2021) dataset