13.9.18

Colas de titanosaurios de Lo Hueco en el XVI Annual Meeting de la EAVP


Los saurópodos titanosaurios de Lo Hueco no podían dejar de estar presentes en el reciente simposio "Sauropod dinosaurs: new insights into their biology, ecology, and evolution" que tuvo lugar en el XVI Annual Meeting de la European Association of Vertebrate Paleontologists (EAVP). En este congreso se ha presentado información sobre los diferentes morfotipos de vértebras caudales de titanosaurio procedentes del yacimiento de Lo Hueco en una comunicación titulada "The morphological variability on titanosaur caudal series from Lo Hueco: taxonomic diversity intra-specific variability of both?. El resumen es el siguiente:

Lo  Hueco  (Cuenca,  Spain)  represents  a  Campanian-Maastrichtian  multitaxic  bonebed,  with  several partial titanosaurian skeletons, mostly articulated or with low dispersion. This accumulation is key for the comprehension of the titanosaur evolutionary history in the European territory. Preliminary studies suggested for the presence of two different taxa (including Lohuecotitan pandafilandi), but recent works  on  axial  remains  are  suggesting  a  higher  diversity. The  detailed  morphological  description  of the abundant caudal vertebral remains of Lo Hueco is necessary to assess this hypothesis. Four distinct caudal morphotypes are recognized: morphotype I) biconvex first caudal, anterodorsally projected neural spines, and long prezygapophyses; morphotype II) neural spine posterodorsally directed and transversely expanded, and postzygapophyses overhanging the centrum posteriorly; morphotype III) transversely compressed, short and vertically oriented neural spines with a distal anteroposterior expansion; and morphotype IV) slightly posteriorly oriented neural spine, with lateral and medial spol and sprl. Morphotype II is possibly represented by two caudal series in different ontogenetic stages showing a substantial variability in the laminae pattern. Morphotype II and Lohuecotitan share a similar morphology on the caudal vertebrae, and the absence of some Lohuecotitan autapomorphies in elements of the morphotype II might be related with intraspecific variability. Morphotype I and III are markedly distinct from the remaining two morphotypes, which seems to support the presence of at least two or three different taxa in Lo Hueco. The phylogenetic relationships of the Ibero-Armorican titanosaurs is debated and this study reveals for the first time, the presence of features traditionally considered as synapomorphies of aeolosaurines.

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