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RE: Hypselospinus (Iguanodontia) from Early Cretaceous of Britain revised
Norman's nomenclature leaves much to be desired. He misuses 'nomen dubium' as
a term for junior synonyms, doesn't get the point of phylogenetic nomenclature,
and redefines most ornithopod clades in terrible ways that are unnecessary
and/or only function in his phylogeny. Hadrosauromorpha's a good idea though.
See my blog post at
http://theropoddatabase.blogspot.com/2014/12/normans-nomenclatures-notoriously.html
for the details.
Mickey Mortimer
----------------------------------------
> Date: Mon, 1 Dec 2014 09:01:15 -0800
> From: bcreisler@gmail.com
> To: dinosaur@usc.edu
> Subject: Hypselospinus (Iguanodontia) from Early Cretaceous of Britain revised
>
> Ben Creisler
> bcreislerf@gmail.com
>
> A new online paper:
>
> David B. Norman FLS (2014)
> On the history, osteology, and systematic position of the Wealden
> (Hastings group) dinosaur Hypselospinus fittoni (Iguanodontia:
> Styracosterna).
> Zoological Journal of the Linnean Society (advance online publication)
> DOI: 10.1111/zoj.12193
> http://onlinelibrary.wiley.com/doi/10.1111/zoj.12193/abstract
>
>
> The history of discovery and interpretation of several dinosaurs
> collected from quarries near the town of Hastings during the latter
> half of the 19th century is more complicated than it should be. Samuel
> Husbands Beckles and Charles Dawson collected several large ornithopod
> skeletons from this area, but just a few bones from these skeletons
> were subsequently described and interpreted (principally) by Richard
> Owen and Richard Lydekker. All these specimens merited recognition
> because they had the potential to contribute to an on-going debate
> about the anatomical structure and relationships of the iconic Wealden
> dinosaur Iguanodon. Unfortunately, no detailed description of these
> important skeletons was published in later years. Furthermore,
> previously known associations of bones and even provenance
> information, linked to the specimens that were gradually acquired by
> the Natural History Museum, are unclear. Confusion may have arisen
> because Richard Lydekker used the private collector Charles Dawson as
> a voluntary curatorial assistant. This account documents the past work
> on the osteology of material that can be attributed to Hypselospinus
> fittoni. Nearly all such material is described here for the first
> time, and every effort has been made to re-establish associations
> between bones as well as provenance information. A skeletal
> reconstruction of Hypselospinus is attempted on the basis of the
> hypodigm. Most of the on-going confusion concerning the affinity of
> this material with either Hy. fittoni or its sympatric contemporary
> Barilium dawsoni has been resolved. Hypselospinus fittoni (Lydekker,
> 1889) is rediagnosed on the basis of this new and relatively
> comprehensive anatomical description, and this animal is compared with
> known contemporary and closely related taxa. Some recently published
> accounts claiming to be revisions of the taxonomy of Wealden
> ‘iguanodonts’, including material belonging to the hypodigm of Hy.
> fittoni, have failed to adhere to basic taxonomic principles and have
> caused more confusion than was strictly necessary. The systematic
> position of Hypselospinus is reassessed cladistically. The cladistic
> analysis forms the basis for a revised hierarchical classification of
> derived ornithopods. The consensus topology generated by the
> systematic analysis has been used to explore the phylogenetic history
> of these dinosaurs and create an internally consistent classificatory
> hierarchy (phylogenetic definitions and Linnaean diagnoses are given
> for critical positions in the topology). This analysis suggests that
> there is a fundamental split amongst the more derived (clypeodontan)
> ornithopod ornithischians into the clades Hypsilophodontia and
> Iguanodontia. There is evidence for anatomical parallelism and
> convergence (homoplasy) particularly between large-bodied
> representatives of both clades. Hypselospinus is one of the earliest
> known styracosternan iguanodontians and displays anatomical
> characteristics that presage the evolution of the extraordinarily
> abundant and diverse hadrosaurs of the latest Cretaceous
> (Campanian−Maastrichtian). These observations cast fresh light on the
> phylogeny, classification, diversity, and biology of derived
> ornithopods. There is little doubt that Hy. fittoni could have been
> understood far better more than a century ago. That this statement is
> undoubtedly true is reflected in the century of doubt and confusion
> that has surrounded this taxon and its original incarnation as
> Iguanodon fittoni.