Thursday, December 17, 2015

[Paleontology • 2015] Morelladon beltrani • A New Sail-Backed Styracosternan (Dinosauria: Ornithopoda) from the Early Cretaceous of Morella, Spain


Morelladon beltrani 
Gasulla, Escaso, Narváez, Ortega & Sanz, 2015
doi:  
10.1371/journal.pone.0144167

Abstract

A new styracosternan ornithopod genus and species is here described based on a partial postcranial skeleton and an associated dentary tooth of a single specimen from the Arcillas de Morella Formation (Early Cretaceous, late Barremian) at the Morella locality, (Castellón, Spain). Morelladon beltrani gen. et sp. nov. is diagnosed by eight autapomorphic features. The set of autapomorphies includes: very elongated and vertical neural spines of the dorsal vertebrae, midline keel on ventral surface of the second to fourth sacral vertebrae restricted to the anterior half of the centrum, a posterodorsally inclined medial ridge on the postacetabular process of the ilium that meets its dorsal margin and distal end of the straight ischial shaft laterally expanded, among others. Phylogenetic analyses reveal that the new Iberian form is more closely related to its synchronic and sympatric contemporary European taxa Iguanodon bernissartensis and Mantellisaurus atherfieldensis, known from Western Europe, than to other Early Cretaceous Iberian styracosternans (Delapparentia turolensis and Proa valdearinnoensis). The recognition of Morelladon beltrani gen. et sp. nov. indicates that the Iberian Peninsula was home to a highly diverse medium to large bodied styracosternan assemblage during the Early Cretaceous.


Systematic Palaeontology

Dinosauria Owen 1842
Ornithischia Seeley 1887
Ornithopoda Marsh 1881

Iguanodontia Dollo, 1888 sensu Norman, 2015 
Ankylopollexia Sereno, 1986 sensu Norman, 2015 
Styracosterna Sereno, 1986 sensu Norman, 2015 

Morelladon gen nov.
urn:lsid:zoobank.org:act:2BEA6D12-8836-4F4C-9616-134FDDC9618E

Morelladon beltrani sp nov.
urn:lsid:zoobank.org:act:EEB70705-B246-48D8-8B79-C5E0A8C6C38C

Etymology: The generic name is derived from Morella (the name of the type locality) and odon (Greek word for “tooth”). The specific name is for Víctor Beltrán, for his involvement and collaboration in the localization of the different fossil sites at the Mas de la Parreta Quarry.

Holotype: CMP-MS-03, a partial skeleton including a complete right dentary tooth, six almost complete dorsal vertebrae, a dorsal centrum, several fragments of dorsals neural spines, two dorsal ribs fragments, a nearly complete sacrum, two haemal arches, ilia, incomplete pubes and ischia, and the right tibia (Figs 2–14). Measurements of select elements of Morelladon beltrani are given in S1 Supporting Information.


Fig 7. Dorsal vertebrae series of the holotype specimen of Morelladon beltrani (CMP-MS-03).


Fig 11. Pelvic girdle of the holotype specimen of Morelladon beltrani (CMP-MS-03).

Fig 1. Geographic location of the holotype specimen of Morelladon beltrani (CMP-MS-03).
(A) Castellón province and Morella locality in Spain. (B) Schematic regional map of area of Morella locality indicating location of the Mas de la Parreta Quarry (black star). (C) Photography showing the location of the holotype site in the CMP-MS area (dash line).

Locality and horizon: The specimen was collected in the Mas de Sabaté (CMP-MS) site within the Mas de la Parreta Quarry at Morella, Spain (Fig 1). The Arcillas de Morella Formation has traditionally been dated as early Aptian in age, but new palynological data indicates a Barremian age for this Iberian Formation.

Fig 16. Phylogenetic relationships of Morelladon beltrani (CMP-MS-03). Time-calibrated strict consensus tree resulting from the analysis of the modified data matrix from Norman .
Abbreviations: AF, Africa; AS, Asia; AU, Australia; EU, Europe; NA, North America, SA, South America.doi:  10.1371/journal.pone.0144167

Conclusions
Despite the limited material known from the type specimen, a suite of autapomorphies supports the validity of Morelladon beltrani. In addition, Morelladon can be distinguished from other styracosternan iguanodontians on the basis of a unique combination of characters. Regardless of the phylogenetic analysis carried out, Morelladon is clearly nested within the clade that contains its synchronic and sympatric contemporary European taxa Iguanodon bernissartensis and Mantellisaurus atherfieldensis, and the lower Albian Proa valdearinnoensis from the Iberian Peninsula.

Styracosternans are by far the most abundantly represented group of dinosaurs in the Arcillas de Morella Formation including, besides Morelladon beltrani, several individuals assigned to Iguanodon bernissartensis and probably to Mantellisaurus atherfieldensis. In addition, the recognition of Morelladon beltrani provides a distinguishing component of the Arcillas de Morella Formation respect to its equivalent upper Wealden facies from northwest Europe (Belgium and England), also characterized by the presence of the medium-large bodied styracosternans Iguanodon bernissartensis and Mantellisaurus atherfieldensis. Finally, the discovery of Morelladon beltrani gen. et sp. nov. combined with other recent named taxa (e.g., Delapparentia turolensis, Proa valdearinnoensis, Iguanodon galvensis) recognizes the Iberian Peninsula as a highly diverse Early Cretaceous medium-large bodied styracosternan assemblage worldwide.


José Miguel Gasulla, Fernando Escaso, Iván Narváez, Francisco Ortega and José Luis Sanz. 2015. A New Sail-Backed Styracosternan (Dinosauria: Ornithopoda) from the Early Cretaceous of Morella, Spain. PLoS ONE. 10(12): e0144167. doi:  10.1371/journal.pone.0144167

New species of 'sail-backed' dinosaur found in Spain http://bit.ly/1OlWhTl via @EurekAlertAAAS

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