[dinosaur] Miragaia new specimen and taxonomy of dacentrurine stegosaurs (free pdf)

Ben Creisler
[email protected]

A new paper in open access:

Francisco Costa & Octávio 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://urldefense.proofpoint.com/v2/url?u=https-3A__doi.org_10.1371_journal.pone.0224263&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=fmSVOFJKdh-s0pB9kpyAFl9wOxuMW6iNvgG-pAimXOs&s=mfZpLpCjxbg6qsrNePdx3Fwz8c1jn0iZAuyKBqm6a5g&e= 
https://urldefense.proofpoint.com/v2/url?u=https-3A__journals.plos.org_plosone_article-3Fid-3D10.1371_journal.pone.0224263&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=fmSVOFJKdh-s0pB9kpyAFl9wOxuMW6iNvgG-pAimXOs&s=QNOvbAs4z1ltAxhIgR8txq2WbN1L0OIWdkr-hKMJn60&e= 
Free pdf:
https://urldefense.proofpoint.com/v2/url?u=https-3A__journals.plos.org_plosone_article_file-3Fid-3D10.1371_journal.pone.0224263-26type-3Dprintable&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=fmSVOFJKdh-s0pB9kpyAFl9wOxuMW6iNvgG-pAimXOs&s=FdHL1hFBYpTpUZlCnXvQRVRH6fAQtz6oTBR875o6frw&e= 

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.