title: The earliest herbivorous marine reptile and its remarkable jaw apparatus.
abstract: Newly discovered fossils of the Middle Triassic reptile Atopodentatus unicus call for a radical reassessment of its feeding behavior. The skull displays a pronounced hammerhead shape that was hitherto unknown. The long, straight anterior edges of both upper and lower jaws were lined with batteries of chisel-shaped teeth, whereas the remaining parts of the jaw rami supported densely packed needle-shaped teeth forming a mesh. The evidence indicates a novel feeding mechanism wherein the chisel-shaped teeth were used to scrape algae off the substrate, and the plant matter that was loosened was filtered from the water column through the more posteriorly positioned tooth mesh. This is the oldest record of herbivory within marine reptiles.
authors.affiliation: Institute of Vertebrate Paleontology and Paleoanthropology, 142 Xizhimenwai Street, Beijing 100044, People's Republic of China.
authors.forename: Li
authors.initials: L
authors.lastname: Chun
authors.affiliation: Field Museum of Natural History, 1400 South Lake Shore Drive, Chicago, IL 60605, USA.
authors.forename: Olivier
authors.initials: O
authors.lastname: Rieppel
authors.affiliation: Wuhan Centre of China Geological Survey, Wuhan, Hubei 430023, People's Republic of China.
authors.forename: Cheng
authors.initials: C
authors.lastname: Long
authors.affiliation: National Museums Scotland, Chambers Street, Edinburgh EH1 1JF, UK.
authors.forename: Nicholas C
authors.identifier: 0000-0003-4408-4640
authors.initials: NC
authors.lastname: Fraser
mesh_terms: D000818:Animals; D005580:Fossils; D060434:Herbivory; D007568:Jaw / Q000033:anatomy & histology*; D010163:Paleontology; D012104:Reptiles / Q000033:anatomy & histology* / Q000502:physiology*
keywords: Atopodentatus unicus; Middle Triassic; marine reptiles; paleontology