Kerberosaurus manakini

[Mickey Mortimer <Mickey_Mortimer111@msn.com>]

Kerberosaurus Bolotsky and Godefroit, 2004
K. manakini Bolotsky and Godefroit, 2004
Late Maastrichtian, Late Cretaceous
Middle Tsagayan Formation, Russia
Holotype- (AENM 1/319) braincase
Referred- (AENM 1/30) frontal
(AENM 1/31) frontal
(AENM 1/32) frontal
(AENM 1/36) squamosal
(AENM 1/38) quadrate
(AENM 1/200) jugal
(AENM 1/222) frontal
(AENM 1/243) prefrontal
(AENM 1/318) nasal
(AENM 1/320) prefrontal
(AENM 1/321) exoccipital-opisthotics
(AENM 1/322) maxilla
(AENM 1/323) maxilla
(AENM 1/324) nasal
Diagnosis- very prominent hook-like palatine process on maxilla;
circumnarial depression limited dorsocaudally by a strong, wide and
flattened crest on the lateral side of the nasal around the external nares;
frontal particularly narrow medio-laterally; rostral margin of parietal
depressed; basisphenoid process of prootic deeply excavated by a pocket-like
depression; groove for ramus ophthalmicus (V1) of trigeminal nerve
particularly widened on lateral side of laterosphenoid; postotic foramina
not limited rostrally by a prominent ridge.
Reference- Bolotsky and Godefroit, 2004. A new hadrosaurine dinosaur from
the Late Cretaceous of far Eastern Russia. Journal of Vertebrate
Paleontology 24(2):351-365.

I'll leave it to Nick to comment on the taxon itself, supposedly just
outside the Prosaurolophus + Saurolophus clade.  But I have a few complaints
about the phylogenetic analysis-

The authors state- "The purpose of the present paper is to establish the
phylogenetic relationships of the new hadrosaurid genus Kerberosaurus, and
not to propose a complete revision of Hadrosaurinae, which would require a
more extended revision of North American specimens. Therefore, we only
retained characters that can be directly observed on the material referred
to as Kerberosaurus manakini at hand, keeping in mind that more exhaustive
studies of hadrosaurid systematics are in preparation (J. J. Head and D. B.
Weishampel, pers. comm.)."
This is NOT a reason to limit character selection to those that can be coded
for your fragmentary taxon.  This only skews the result of the analysis.
Characters not codable for Kerberosaurus might nonetheless affect clades it
belongs to.  WHY don't the authors realize this?

They continue- "Autapomorphic characters have also been excluded from the
present analysis."
Then why are 4 of the 21 characters autapomorphic for the OTU
Lambeosaurinae?

Finally- "Because missing data may influence cladistic analysis in rather
unpredictable ways (Platnick et al., 1991), we also left out taxa known to
be too incomplete, or requiring systematic revision, such as Hadrosaurus
foulkii Leidy, 1858, Kritosaurus navajovius Brown, 1910 (5Anasazisaurus
horneri Hunt and Lucas, 1993 1 Naashibitosaurus ostromi Hunt and Lucas,
1993), Lophorhothon atopus Langston, 1960, Claosaurus agilis (Marsh, 1872),
Secernosaurus koerneri Brett-Surman, 1979, Aralosaurus tuberiferus
Rozhdestvensky, 1968, or Shantungosaurus giganteus Hu, 1973."
WHEN will people learn poorly coded taxa do NOT negatively influence
results?  They _can_, but they can also have definite placements, or their
unique character combinations can suggest better results.

In any case, the analysis of so few characters, obviously designed to have a
preconceived result (CI = .92), is of little use.  I mean, there are two
(count them- two) discordent codings in the matrix (Maisaura lacks character
7, unlike other hadrosaurines; lambeosaurines and saurolophins both have
character 21).  The Sereno-esque "analyses" must stop!

Mickey Mortimer