Crocs in CJES

[Brad McFeeters <archosauromorph2@hotmail.com>]

Göhlich, Ursula B., Luis M. Chiappe, James M. Clark & Hans-Dieter Sues, 
2005.  The systematic position of the Late Jurassic alleged dinosaur 
*Macelognathus* (Crocodylomorpha: Sphenosuchia).  Canadian Journal of Earth 
Sciences 42 (3): 307-321.

Abstract:  *Macelognathus vagans* was described by O.C. Marsh in 1884, based 
on a mandibular symphysis from the Upper Jurassic Morrison Formation of 
Wyoming. Often considered a dinosaur but later tentatively referred to the 
Crocodylia, its phylogenetic identity has until now been enigmatic. New 
material of this species from the Morrison Formation of western Colorado 
demonstrates its affinities with basal crocodylomorphs commonly grouped 
together as the Sphenosuchia, which are characterized by a gracile 
postcranial skeleton with erect limb posture. *Macelognathus* shares 
features with *Kayentasuchus* from the Lower Jurassic Kayenta Formation of 
Arizona and *Hallopus*, which may be from the Morrison Formation of eastern 
Colorado. The new material constitutes the youngest definitive occurrence of 
a sphenosuchian, previously known from the Late Triassic to the Middle or 
Late? Jurassic.

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Jouve, Stéphane, 2005.  A new description of the skull of *Dyrosaurus 
phosphaticus* (Thomas, 1893) (Mesoeucrocodylia: Dyrosauridae) from the Lower 
Eocene of North Africa.  Canadian Journal of Earth Sciences 42 (3): 323-337.

Abstract: *Dyrosaurus phosphaticus* (Thomas 1893) has been described several 
times, but the poor preservation and the incomplete preparation of the 
material left this species inadequately described. Further preparation of a 
specimen referred to this species now allows a complete description of the 
braincase and its various cranial nerves. Dyrosaurid taxonomy is mainly 
based on mandibular characters and the complete description of the skull of 
*D. phosphaticus*, and comparison with the other known species of the family 
enables enhancement of other taxonomic characters. An emended diagnosis is 
given for *D. phosphaticus*, the only known species of this genus. With this 
new description, new characteristics that enable comparisons with other 
crocodyliforms are available. The presence of a distinct anterolateral 
postorbital process is observed in dyrosaurs, *Elosuchus*, *Terminonaris 
robusta*, some *Goniopholis*, and, although smaller, in *Sarcosuchus 
imperator*. In the dyrosaurids *D. phosphaticus* and *Rhabdognathus*, the 
postorbital participates largely in the dorsal margin of the infratemporal 
fenestra, as in *Elosuchus*, *S. imperator*, and Thalattosuchia. The 
laterodorsal position of the lateral eustachian foramen in dyrosaurids is 
similar to those of *Elosuchus* and thalattosuchians. These characters are 
not shared by *Stolokrosuchus lapparenti* (included in the family 
Elosuchidae with *Elosuchus*), suggesting that without clear phylogenetic 
analysis, the creation of the Elosuchidae was premature. A preliminary 
phylogenetic analysis based on comparisons of *D. phosphaticus* with other 
dyrosaurids shows that *Phosphatosaurus gavialoides* and *Sokotosuchus 
ianwilsoni* are the most primitive dyrosaurids, and *Rhabdognathus* is more 
closely related to *Hyposaurus* than to *D. phosphaticus*.