Phyllodon

Phyllodon is based on MGSP G5, a partial lower jaw tooth recovered from a lignite marl in a mine near the city of Leiria. Richard Thulborn, who described the genus, added an upper beak tooth (MGSP G2). He regarded the new genus as a hypsilophodontid, and presented a conjectural restoration of the tooth arrangement.{{cite journal |last=Thulborn |first=Richard A. |year=1973 |title=Teeth of ornithischian dinosaurs from the Upper Jurassic of Portugal, with description of a hypsilophodontid (Phyllodon henkeli gen. et sp. nov.) from the Guimarota lignite. |journal=Memória Serivoços Geológicos de Portugal |series=Nova Série |volume=22 |pages=89–134 }} Peter Galton, reviewing Late Jurassic North American hypsilophodontids a few years later, found that the Phyllodon teeth best matched those of Nanosaurus, and agreed with a hypsilophodontid identity because the lower jaw tooth is asymmetric in front and back views.{{cite journal |last=Galton |first=Peter M. |authorlink=Peter Galton |year=1983 |title=The cranial anatomy of Dryosaurus, a hypsilophodontid dinosaur from the Upper Jurassic of North America and East Africa, with a review of hypsilophodontids from the Upper Jurassic of North America |journal=Geologica et Palaeontologica |volume=17 |pages=207–243 }}

Sometime before 2004, possible Phyllodon remains were recovered from the Chipping Norton Limestone of England. It is likely that these remains actually belonged to an indeterminate ornithischian separate from Phyllodon."10.3 Gloucestershire, England; 2. Chipping Norton Formation," in Weishampel, et al. (2004). Page 538.

Because of the sparse material, Phyllodon has often been tossed off as a dubious basal ornithopod of uncertain affinities.{{cite book |last=Sues |first=Hans-Dieter |author2=Norman, David B. |editor= Weishampel, David B. |editor2=Dodson, Peter |editor3=Osmólska, Halszka|title=The Dinosauria |edition=1st |year=1990 |publisher=University of California Press |location=Berkeley |isbn=0-520-06727-4 |pages=498–509 |chapter=Hypsilophodontidae, Tenontosaurus, Dryosauridae}}{{cite book |last=Norman |first=David B. |authorlink=David B. Norman |author2=Sues, Hans-Dieter |author3=Witmer, Larry M. |author4= Coria, Rodolfo A. |editor=Weishampel, David B. |editor2=Dodson, Peter |editor3=Osmólska, Halszka |title=The Dinosauria |url=https://archive.org/details/dinosauriandedit00weis |url-access=limited |edition=2nd |year= 2004|publisher=University of California Press |location=Berkeley |isbn=0-520-24209-2 |pages=[https://archive.org/details/dinosauriandedit00weis/page/n411 393]–412 |chapter=Basal Ornithopoda}} However, more material that might belong to this genus has been recovered from the original locality and described. Included in this material are over 120 more teeth from all parts of the jaw and four partial lower jaws with the teeth lost. Oliver Rauhut, who described the new material, tentatively identified the lower jaws as Phyllodon due to there being no other similar dinosaurs found at the locality. The teeth were very small (up to 3 millimeters across, or 0.1 inches) and possibly juvenile. He also found additional diagnostic characteristics for Phyllodon in the new material, including very tall upper jaw teeth, indicating that it could be a valid genus after all. After comparing it to other hypsilophodonts, he found that it best matched the roughly contemporaneous Drinker of the North American Morrison Formation, with various details suggesting that they were closely related.{{cite journal |last=Rauhut |first=Oliver W.M. |year=2001 |title=Herbivorous dinosaurs from the Late Jurassic (Kimmeridgian) of Guimarota, Portugal |journal=Proceedings of the Geologists' Association |volume=112 |pages=275–283 |doi=10.1016/S0016-7878(01)80007-9 |issue=3 |bibcode=2001PrGA..112..275R }} Similarly, Galton found its teeth to be similar to those of Drinker and Nanosaurus in his 2006 review.{{cite book |last=Galton |first=Peter M. |authorlink=Peter Galton |editor= Carpenter, Kenneth |title=Horns and Beaks: Ceratopsian and Ornithopod Dinosaurs |year=2006 |publisher=Indiana University Press |location=Bloomington and Indianapolis |isbn=0-253-34817-X |pages=17–47 |chapter=Teeth of ornithischian dinosaurs (mostly Ornithopoda) from the Morrison Formation (Upper Jurassic) of the western United States }}

As a hypsilophodontid or other basal ornithopod, Phyllodon would have been a bipedal herbivore. Its size has not been estimated, but as most adult hypsilophodonts were {{convert|1|–|2|m|ft|sp=us}} long, this genus would probably have been of similar size. Its similarity to the North American Drinker and Nanosaurus is another piece of evidence linking Late Jurassic Portuguese dinosaur faunas with the contemporaneous Morrison Formation dinosaurs.{{cite book|title=Paleontology and Geology of the Upper Morrison Formation|year=2006|chapter=Late Jurassic dinosaurs from the Morrison Formation (USA), the Lourinhã and Alcobaça Formations (Portugal), and the Tendaguru Beds (Tanzania): a comparison|editor1=Foster, John R. |editor2=Lucas, Spencer G. |author=Mateus, Octávio |pages=223–231 |publisher=New Mexico Museum of Natural History and Science |location=Albuquerque, New Mexico |series=New Mexico Museum of Natural History and Science Bulletin (36)}}

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{{Ornithischia|O.}}

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Category:Neornithischia

Category:Dinosaur genera

Category:Kimmeridgian dinosaurs

Category:Taxa named by Richard A. Thulborn

Category:Fossil taxa described in 1973

Category:Dinosaurs of Portugal