Fona ( ; ) is an extinct genus of thescelosaurine thescelosaurid ornithischian dinosaurs from the 'mid'-Cretaceous Cedar Mountain Formation (Mussentuchit Member) of Utah, United States. The genus contains a single species, F. herzogae, known from several partial skeletons and skulls. Based on anatomical similarities to the closely related and similarly aged Oryctodromeus, Fona was likely a semi-fossorial animal, likely spending a significant amount of time in underground burrows. It also represents the oldest known definitive thescelosaurine.
Fona ( ; ) is an extinct genus of thescelosaurine thescelosaurid ornithischian dinosaurs from the 'mid'-Cretaceous Cedar Mountain Formation (Mussentuchit Member) of Utah, United States. The genus contains a single species, F. herzogae, known from several partial skeletons and skulls. Based on anatomical similarities to the closely related and similarly aged Oryctodromeus, Fona was likely a semi-fossorial animal, likely spending a significant amount of time in underground burrows. It also represents the oldest known definitive thescelosaurine.
== Discovery and naming == The Fona fossil material was discovered in multiple different localities of the Mussentuchit Member of the Cedar Mountain Formation in Emery County of Utah, United States. The holotype specimen, NCSM 33548, was found in the 'Karmic Orodromine locality' and represents the only certain occurrence of Fona in the lower Mussentuchit Member. This specimen consists of mostly complete and somewhat articulated skeleton. Other outcrops yielded several other specimens referrable to Fona based on similarities in the skeletal anatomy. FMNH PR 4581 was found in the 'Manolo site', which is slightly younger than the holotype locality. It is also a mostly complete skeleton, missing most of the cranium, pelvis, and metatarsals. The youngest rocks with Fona material represent the 'Mini Troll locality'. Here, the skeletons of two well preserved, similarly sized individuals were found together, as well as some bones of juvenile specimens. alt=Skeletal diagram of Fona herzogae, a thescelosaurine dinosaur|thumb|Skeletal reconstruction Prior to the formal naming of Fona, the fossil material was reported in several conference abstracts and academic papers without thorough description, where it was typically mentioned as belonging to an orodromine thescelosaurid.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).