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Re: September JVP: Anchiceratops and Alamosaurus

Also some interesting stuff on Cenozoic birds... those big-headed,
short-tailed, bent-legged oddballs that carried the Theropoda banner
beyond the Cretaceous...

Degrange, FJ and Tambussi, CP (2011) Re-examination of Psilopterus
lemoinei (Aves, Phorusrhacidae), a late early Miocene little terror
bird from Patagonia (Argentina).  Journal of Vertebrate Paleontology
31(5): :1080–1092.

ABSTRACT: Psilopterus lemoinei, the largest species in this genus, was
a small terror bird weighing 8–9 kg, and was a ground bird with
functionally tridactyl feet. New remains of this phorusrhacid,
including an exceptionally preserved anterior part of a skull
recovered from the Patagonian Killik Aike Norte locality (Santa Cruz
Formation, late early Miocene), is now available for study. The main
purpose of this paper is to provide a detailed morphological
description of Psilopterus lemoinei. The new fossils show for the
first time that the internal structure of the beak is hollow and
reinforced with thin-walled trabeculae. The absence of zona flexoria
palatina and zona flexoria arcus jugalis are key features related to
the evolution of cranial akinesis. Homologies of the narial and
fenestra antorbitalis boundaries have been clarified. Our
re-examination allows the establishment of primary osteological
homologies useful in comparative anatomy, functional morphology, and
phylogenetic studies.

Although I have my doubts about seriemas being the sister group to a
Falconidae+Psittaciformes+Passeriformes clade (just as I have doubts
about Eufalconimorphae), it's nice to see the seriemas and
phorusrhacids getting their own "order" (Cariamiformes).

Worthy, TH, Tennyson, AJD, and Scofield, RP (2011) An early Miocene
diversity of parrots (Aves, Strigopidae, Nestorinae) from New Zealand.
 Journal of Vertebrate Paleontology 31(5): 1102-1116.

ABSTRACT: A new genus and three species of parrot (Psittaciformes,
Strigopidae, Nestorinae) are described from the early Miocene (19–16
Ma) St Bathans Fauna of Otago, New Zealand, based on 85 fossils as
follows: Nelepsittacus minimus (17), N. donmertoni (60), and N.
daphneleeae (6), with two additional fossils representing a fourth
unnamed taxon. These taxa range from small parrots approximately the
size of Cyanoramphus species to one as large as the living Nestor
notabilis. Apomorphies in the coracoid, humerus, tibiotarsus, and
tarsometatarsus ally Nelepsittacus with Nestor and exclude a close
relationship with Strigops, the other endemic genus assumed to have
had a long history in New Zealand. With only nestorine parrots
represented, the St Bathans Fauna has nothing in common with the
Australian psittaciform fauna, in which cacatuids and a diversity of
psittacid genera exist. These data add to the growing body of evidence
that the New Zealand terrestrial vertebrate fauna, at a time minimally
3 Ma after the maximal marine inundation of Zealandia in the late
Oligocene, was highly endemic, with no close relationship to the
closest faunas in Australia. This high degree of endemism strongly
suggests that the Zealandian terrestrial biota persisted, at least in
part, through the Oligocene highstand in sea level.

Clever name: In Greek mythology, Neleus (after which Nelepsittacus was
named) was the father of Nestor.

On Sat, Sep 10, 2011 at 12:17 AM, Brad McFeeters
<archosauromorph2@hotmail.com> wrote:
> Mallon, J.C., R. Holmes, D.A. Eberth, M.J. Ryan & J.S. Anderson, 2011.  
> Variation in the skull of *Anchiceratops* (Dinosauria, Ceratopsidae) from the 
> Horseshoe Canyon Formation (Upper Cretaceous) of Alberta.  Journal of 
> Vertebrate Paleontology 31(5): 1047-1071.
> Abstract: *Anchiceratops* is a chasmosaurine ceratopsid from the Upper 
> Cretaceous Horseshoe Canyon Formation (HCF) of Alberta. It is distinguished 
> primarily by its unique parietosquamosal frill ornamentation and possibly by 
> the presence of a ventrally flexed olfactory bulb of the brain. Although 
> *Anchiceratops* is known from at least ten partial skulls, only two of these 
> have been formally described. These skulls are not stratigraphically 
> segregated, but they differ markedly in their proportions (e.g., supraorbital 
> horncore and frill dimensions), causing previous authors to account for this 
> disparity with reference to either interspecific or sexual differences. Both 
> of these hypotheses assume that variation in *Anchiceratops* is dimorphic; 
> however, this assumption has never been tested with reference to all 
> available material. The present study describes all material from the HCF 
> that can be positively attributed to *Anchiceratops*, and tests the 
> assumption of dimorphism by subjecting this material to a series of 
> morphometric analyses. We find no compelling evidence for dimorphism in 
> *Anchiceratops*, although sample size is still too small for convincing 
> statistical support. We conclude that there is a single, variable species of 
> *Anchiceratops*, *A. ornatus*. Average sedimentation rates for the HCF 
> suggest that *A. ornatus* is a particularly long-lived species compared with 
> other ceratopsids (1.5–2.0 Ma), and the paleoecological implications of this 
> are discussed. A cladistic analysis that includes the new data presented here 
> indicates that *Anchiceratops* is more closely related to *Chasmosaurus* than 
> to *Triceratops*, in contrast with previous studies.
> D'emic, M.D., J.A. Wilson & T.E. Williamson, 2011.  A sauropod dinosaur pes 
> from the latest Cretaceous of North America and the validity of *Alamosaurus 
> sanjuanensis* (Sauropoda, Titanosauria).  Journal of Vertebrate Paleontology 
> 31(5):1072-1079.
> Abstract: Complete sauropod pedes are rare in the fossil record, which has 
> limited their use in systematics. We describe a nearly complete, large 
> sauropod pes from the Maastrichtian-age Naashoibito Member of the Kirtland 
> Formation of New Mexico, U.S.A., that bears synapomorphies of some eusauropod 
> clades, such as the presence of metatarsal I with a wide shaft and laterally 
> deflected pedal unguals. Novel pedal characters presented herein, such as the 
> presence of an embayment on the proximomedial corner of metatarsal IV, 
> suggest that the Naashoibito specimen likely belongs to a titanosauriform. 
> Based on its provenance, the Naashoibito specimen likely belongs to the 
> derived titanosaur *Alamosaurus sanjuanensis*, which is the only recognized 
> Late Cretaceous titanosaur in North America. However, formal referral to 
> *Alamosaurus* awaits discovery of overlapping materials with the holotype or 
> definitively referred remains. The holotypic scapula of *Alamosaurus 
> sanjuanensis* is diagnostic, providing a basis for referral of some other 
> Maastrichtian North American titanosaur specimens to the genus. Confirmation 
> of these referrals and the description of the pes presented herein augment 
> the data relevant to the systematic problems that have historically 
> surrounded *Alamosaurus*.