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RE: Crocodilians by the millions! Special issue of Zoological Journal!



Very cool papers.  I like the detail in de Andrade et al.'s Goniopholis paper, 
but have a nit pick.  There are apparently two taxa which have been suggested 
to be synonyms- Siamosuchus phuphokensis and "Goniopholis" phuwiangensis.  The 
authors run both in their analysis and find them to have similar but different 
positions, which is fine.  But then "in order to evaluate the possibility that 
‘G.’ phuwiangensis is at least congeneric with Si. phuphokensis, a fourth 
additional analysis was carried out, using a single terminal to combine the 
non-overlapping data on both taxa." The authors find it "has a feeble impact on 
the final indexes, when compared to the second supplementary run, and increases 
the final number of topologies obtained, resulting in a less resolved 
consensus,"  Which is interesting, but troublingly they conclude "These results 
indicate that there is no support for the idea that ‘G.’ phuwiangensis is more 
related to Siamosuchus than to Sunosuchus or Eutretauranosuchus..."  

But they indicate no such thing.  If you combine parts of unrelated taxa and 
run the chimaera in an analysis, there's no greater liklihood the resulting 
trees will have "better" indices or more most parsimonious trees.  For 
instance, imagine if your analysis included two alvarezsaurids, Alvarezsaurus 
and Mononykus.  Then you run another analysis, but with Mononykus' front half 
joined with Ornitholestes' back half.  It would probably have a better 
consistancy index, merely because you wouldn't have all of the extra 
parvicursorine-bird convergences in the pelvis and hindlimb.  But those 
convergences are real.  de Andrade et al. make the mistake Peters does in 
thinking a low consistancy index is better, when really it all depends on how 
much homoplasy is in the real tree.  Similarly, you could imagine that the 
normal tree might have alvarezsaurids in a trichotomy with ornithomimosaurs and 
maniraptorans, but maybe the maniraptoran similarity is due to posterior 
characters of Mononykus, and the more basal posterior morphology of 
Ornitholestes moves the partially chimaerical Alvarezsauridae sister to 
Ornithomimosauria in all trees.  Then the chimaerical analysis would have a 
more resolved consensus than the real analysis.  I have no idea if these kinds 
of conditions are affecting the crocodilian analyses and no opinion on the 
synonymy of the two taxa I hadn't heard of before today, but authors need to 
understand how phylogenetic analysis works.

Mickey Mortimer

----------------------------------------
> Date: Fri, 13 Jan 2012 10:41:33 -0800
> From: bcreisler@gmail.com
> To: dinosaur@usc.edu
> Subject: Crocodilians by the millions! Special issue of Zoological Journal!
>
> From: Ben Creisler
> bcreisler@gmail.com
>
>
> This item came out yesterday but has not been mentioned yet on the
> DML. A special supplement issue of the Zoological Journal of the
> Linnean Society is devoted to the 1st Symposium on the Evolution of
> Crocodyliforms. All the pdfs are FREE!
>
>
> http://onlinelibrary.wiley.com/doi/10.1111/zoj.2011.163.issue-s1/issuetoc
>
>
> Many Mesozoic crocs are discussed and some new genera and species are
> described. I'll cite the new taxa for now. The correct date for these
> taxa is a bit murky--it's officially the December 2011 issue but it
> was put on line (published?) in 2012. The "how to cite" feature says
> 2011.
>
>
>
> Caryonosuchus
>
> KELLNER, A. W. A., CAMPOS, D. A., RIFF, D. and DE ANDRADE, M. B. (2011)
> A new crocodylomorph (Sphagesauridae, Notosuchia) with horn-like
> tubercles from Brazil. Zoological Journal of the Linnean Society, 163:
> S57-S65.
> doi: 10.1111/j.1096-3642.2011.00712.x
> http://onlinelibrary.wiley.com/doi/10.1111/j.1096-3642.2011.00712.x/abstract
>
>
> A new species of a bizarre notosuchian mesoeucrocodylian is reported
> here. Caryonosuchus pricei gen. et sp. nov. was found in the outcrops
> of the Adamantina Formation (Campanian-Masstrichtian) in São Paulo
> State, Brazil, and shows a typical sphagesaurid dentition: strong and
> short teeth, obliquely implanted with the crown of the upper teeth
> showing a rounded anteriolabial margin and a strong compressed
> posteriolingual edge developed into a carina, ornamented by developed
> ridges and denticles. Amongst the diagnostic features of the new taxon
> are the presence of horn-like tubercles on the premaxilla and maxilla,
> never reported in this group before. The occurrence of C. pricei
> increases the diversity of sphagesaurids and confirms that all members
> of this clade, only recorded in Late Cretaceous deposits from Brazil
> so far, share the same dentition.
>
> ===
>
>
> DE ANDRADE, M. B., EDMONDS, R., BENTON, M. J. and SCHOUTEN, R. (2011)
> A new Berriasian species of Goniopholis (Mesoeucrocodylia, Neosuchia)
> from England, and a review of the genus.
> Zoological Journal of the Linnean Society, 163: S66-S108.
> doi: 10.1111/j.1096-3642.2011.00709.x
> http://onlinelibrary.wiley.com/doi/10.1111/j.1096-3642.2011.00709.x/abstract
>
> A new species, Goniopholis kiplingi sp. nov., based on an
> exceptionally preserved skull from the Lower Cretaceous of England is
> described in detail. It shows great similarity with Goniopholis simus
> and Goniopholis baryglyphaeus, but can be distinguished by the
> presence of longer lachrymals, smooth (not edged) dorsal surface of
> the quadrate, and proportionally longer rostrum. A comprehensive
> phylogenetic analysis of Mesoeucrocodylia (104 taxa; 486 characters)
> focused on goniopholidids (14 species) places G. kiplingi as
> sister-group of G. simus, and as part of a monophyletic group also
> containing G. baryglyphaeus. The relationships of Nannosuchus
> gracilidens and three undescribed European taxa are explored, and
> preliminary analyses of Denazinosuchus kirtlandicus (Upper Cretaceous,
> USA) and 'Goniopholis' phuwiangensis (Lower Cretaceous, Thailand) are
> presented. The assignment of taxa to the genus Goniopholis is
> discussed. Goniopholis, in its traditional sense, is considered
> paraphyletic and a restricted updated definition is proposed, with
> comments on the evolution of other goniopholidids. Morphological
> characteristics of fragmentary material attributed to Goniopholis are
> not considered sufficient to secure their generic/specific assignment,
> and provide no support for the presence of Goniopholis in Gondwanan
> and/or Upper Cretaceous sedimentary units. Currently Goniopholis is
> restricted to the Upper Jurassic-Lower Cretaceous of Europe.
>
> ===
>
> Labidiosuchus
>
> KELLNER, A. W. A., FIGUEIREDO, R. G., AZEVEDO, S. A. K. and CAMPOS, D. A. 
> (2011)
> A new cretaceous notosuchian (Mesoeucrocodylia) with bizarre dentition
> from Brazil. Zoological Journal of the Linnean Society, 163:
> S109-S115.
> doi: 10.1111/j.1096-3642.2011.00711.x
> http://onlinelibrary.wiley.com/doi/10.1111/j.1096-3642.2011.00711.x/abstract
>
>
> A new species of Notosuchia, Labidiosuchus amicum gen. et sp. nov., is
> described based on an incomplete lower jaw (DGM 1480-R) from the Upper
> Cretaceous Marília Formation (Maastrichtian) recovered from a quarry
> near the Peirópolis municipality, Minas Gerais State, Southeastern
> Brazil. The mandibular symphysis is long, strong anterodorsally
> projected and 'Y-shaped'. The bizarre dentition is formed by at least
> eight teeth placed in a symphyseal tooth battery, some located lateral
> to each other. The first pair is larger than all others and
> procumbent. Some teeth are obliquely implanted (anterolabially to
> posterolingually) and have sub circular to elliptical outline. At
> least the posterior teeth are single cuspidate with acute apex.
> Labidiosuchus amicum shows a rather bizarre dentition, increasing the
> taxonomic diversity and potential feeding strategies of notosuchian
> crocodylomorphs.
>
> ====
>
> Fruitachampsa
>
> CLARK, J. M. (2011)
> A new shartegosuchid crocodyliform from the Upper Jurassic Morrison
> Formation of western Colorado.
> Zoological Journal of the Linnean Society, 163: S152-S172.
> doi: 10.1111/j.1096-3642.2011.00719.x
> http://onlinelibrary.wiley.com/doi/10.1111/j.1096-3642.2011.00719.x/abstract
>
>
>
> A small new basal crocodyliform, Fruitachampsa callisoni gen. nov.,
> sp. nov., is represented by several partial skeletons from the
> Morrison Formation at the Fruita Paleontological Area near Grand
> Junction, Colorado. It is placed in the Family Shartegosuchidae
> Efimov, 1988, previously comprising three genera from the Late
> Jurassic locality of Shar Teeg in western Mongolia and possibly a
> fourth genus from the Early Cretaceous of Siberia. Shartegosuchids
> share a sculpted palatal surface of the pterygoids, the absence of a
> mandibular fenestra, and posterior maxillary teeth and post-caniniform
> dentary teeth with a flat and horizontal apical region and vertical
> crenulations extending basally from it. Fruitachampsa and
> Shartegosuchus form a clade supported by ventral half of the lacrimal
> tapering ventroposteriorly, sculpturing on palatines, and lower teeth
> absent anterior to caniniforms. The shartegosuchids are most
> parsimoniously considered to be outside of the mesoeucrocodylian clade
> and are possibly allied with the Asian taxa Shantungosuchus,
> Sichuanosuchus, and Zosuchus. Fruitachampsa is unusual in possessing a
> series of small protuberances along the occipital margin of the
> parietal and squamosal and procoelous vertebrae, and lacking an
> antorbital fenestra or fossa. This is the first occurrence of a
> shartegosuchid in North America, and the close relationship of
> Fruitachampsa with Shartegosuchus nested among other Asian taxa
> indicates it dispersed to North America from Asia.
>
> ====
>
> Pietraroiasuchus
>
> BUSCALIONI, A. D., PIRAS, P., VULLO, R., SIGNORE, M. and BARBERA, C. (2011)
> Early eusuchia crocodylomorpha from the vertebrate-rich Plattenkalk of
> Pietraroia (Lower Albian, southern Apennines, Italy).
> Zoological Journal of the Linnean Society, 163: S199-S227.
> doi: 10.1111/j.1096-3642.2011.00718.x
> http://onlinelibrary.wiley.com/doi/10.1111/j.1096-3642.2011.00718.x/abstract
>
>
> The locality of Pietraroia (Lower Albian, southern Apennines, Italy)
> has provided two fully articulated crocodylomorphs, exposed in ventral
> and in dorsal aspect, which are described here as representing a new
> species of a new genus, Pietraroiasuchus ormezzanoi gen. nov, sp. nov.
> The new taxon is found to be the sister taxon of Pachycheilosuchus
> trinquei from the Albian of the Glen Rose Formation, Texas.
> Pietraroiasuchus ormezzanoi resolves the phylogenetic position of the
> controversial P. trinquei, and is crucial in enabling an extensive
> understanding of the family Hylaeochampsidae. Phylogenetic analysis
> places Hylaeochampsa vectiana as a sister group of Iharkutosuchus
> makadii plus Pachycheilosuchus and Pietraroiasuchus. The phylogenetic
> result reveals the presence of an evolutionary mosaicism within
> non-crocodylian eusuchians. Mosaic features in Pietraroiasuchus are
> denoted by the combination of primitive character states, such as the
> position of the choana with its anterior margin formed by an inverted
> V-shaped palatine processeses, and the presumed presence of a tiny
> antorbital fossa, in conjunction with derived states involving the
> slight vertebral procoelia, the presence of tetraserial segmented
> dermal armour with an accessory lateral row, and isolated nuchal
> osteoderms. The disjoint occurrence between Pachycheilosuchus and
> Pietraroiasuchus species suggests that Pietraroia was a refuge island
> inhabited by endemic forms.
>
> ===
>
> Not a new taxon, but relevant to dinosaurs:
>
>
> RIFF, D. and KELLNER, A. W. A. (2011)
> Baurusuchid crocodyliforms as theropod mimics: clues from the skull
> and appendicular morphology of Stratiotosuchus maxhechti (Upper
> Cretaceous of Brazil).
> Zoological Journal of the Linnean Society, 163: S37-S56.
> doi: 10.1111/j.1096-3642.2011.00713.x
> http://onlinelibrary.wiley.com/doi/10.1111/j.1096-3642.2011.00713.x/abstract
>
> The Baurusuchidae crocodyliforms are usually interpreted as active
> terrestrial predators, but only some positive evidence of such habits
> has been described to date, mainly the relative position of external
> nares and orbits. Here we describe features that support this view in
> a complete specimen of the Baurusuchidae Stratiotosuchus maxhechti,
> and have executed a parsimony analysis to confirm their phylogenetic
> position. S. maxhechti exhibits theropodomorph features that have been
> previously recognized in skulls of the Baurusuchidae, as well as
> postcranial characteristics related to a parasagittal gait, showing
> that the similarities between the Baurusuchidae and theropods extend
> beyond the cranial morphology. These include a well-developed
> supracetabular crest, a relatively medially offset femoral head and a
> caudally orientated calcaneal tuber. The orientations of the surfaces
> for muscular attachments imply that the appendicular movements of S.
> maxhechti were mainly anteroposterior, with abduction significantly
> constrained. S. maxhechti presents features that mimic some present in
> theropods, including a 'fossa brevis' on the ilium and tubercles on
> the ischium and femur similar to the obturator process and accessory
> trochanter. The relative proportions of the femur, tibia, and longer
> metatarsal are more similar to those of Postosuchus than to other
> Crocodylomorpha. In the skull, besides the theropodomorph (ziphodont)
> dentition concentrated in the anterior half of the rostrum, the
> baurusuchids are remarkable by the fusion of the nasals, which can be
> related to a large resistance against feeding forces acting on a
> high-profile skull. The appendicular morphology of S. maxhechti
> strengthens the interpretation that the Baurusuchidae were active
> land-dwelling predators in the Upper Cretaceous of south-eastern
> Brazil, occuping ecological niches typical of small to medium-sized
> theropod dinosaurs.