The abstract's final sentence understates their point: they sink Alcovasaurus into Miragaia.On Wed, Nov 13, 2019 at 1:55 PM Ben Creisler <bcreisler@gmail.com> wrote:Ben CreislerA new paper in open access:Francisco Costa & OctÃvio Mateus (2019)
Dacentrurine stegosaurs (Dinosauria): A new specimen of Miragaia longicollum from the Late Jurassic of Portugal resolves taxonomical validity and shows the occurrence of the clade in North America
PLoS ONE 14(11): e0224263.
doi: https://doi.org/10.1371/journal.pone.0224263
https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0224263
Free pdf:
https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0224263&type=printable
The stegosaur species Miragaia longicollum was erected based on a partial anterior skeleton from the Upper Jurassic of Portugal. Until then, almost all stegosaur specimens in Portugal and Spain had been identified as Dacentrurus armatus, the sister taxon of M. longicollum and only other member of the clade Dacentrurinae. The holotypes of the two species have little overlap, since the holotype of D. armatus is mostly a posterior skeleton, so the classification of other specimens to either species is unclear and the validity of M. longicollum has been questioned and debated. Here we describe a largely complete specimen of M. longicollum discovered in 1959 in Atouguia da Baleia, Peniche, Portugal, consisting of both anterior and posterior portions of the skeleton. Comparisons to the holotypes of dacentrurines and other stegosaurs shed light on the convoluted relationships of this group. We conclude that M. longicollum is valid and rather different from D. armatus, and provide a revised diagnosis of M. longicollum, as well as revised diagnoses for D. armatus, Dacentrurinae, and the first diagnosis of the genus Miragaia, granting stability to these taxa and allowing new considerations to be given on the classification of other Iberian stegosaurs. This new specimen is, to date, the most complete dinosaur described from Portugal and the most complete stegosaur described from Europe. Miragaia shared anatomical features that show a close affinity to Alcovasaurus longispinus, confirming this to be the first known dacentrurine stegosaur in America, coherent with the hypothesis of an ephemeral land bridge between North America and Iberia that allowed faunal exchange.--Thomas R. Holtz, Jr.
Email:Âtholtz@umd.eduÂÂÂÂÂÂÂÂ Phone: 301-405-4084
Principal Lecturer, Vertebrate PaleontologyOffice: Geology 4106, 8000 Regents Dr., College Park MD 20742
Dept. of Geology, University of Maryland
http://www.geol.umd.edu/~tholtz/Phone: 301-405-6965
Fax: 301-314-9661ÂÂÂÂÂÂ ÂÂÂÂÂÂÂ
Faculty Director, Science & Global Change Program, College Park ScholarsOffice: Centreville 1216, 4243 Valley Dr., College Park MD 20742
http://www.geol.umd.edu/sgc
Fax: 301-314-9843
Mailing Address:ÂÂÂÂÂÂÂ Thomas R. Holtz, Jr.
ÂÂÂÂÂÂÂ ÂÂÂÂÂÂÂ ÂÂÂÂÂÂÂ Department of Geology
ÂÂÂÂÂÂÂ ÂÂÂÂÂÂÂ ÂÂÂÂÂÂÂ Building 237, Room 1117ÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂÂ 8000 Regents Drive
ÂÂÂÂÂÂÂ ÂÂÂÂÂÂÂ ÂÂÂÂÂÂÂ University of Maryland
ÂÂÂÂÂÂÂ ÂÂÂÂÂÂÂ ÂÂÂÂÂÂÂ College Park, MD 20742-4211 USA