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New dinosaurs Ahshislepelta, Amtocephale, pterosaur Navajodactylus and more pdfs

From: Ben Creisler

Robert Sullivan has recently posted a host of new papers 
in the New Mexico Museum of Natural History and Science 
Bulletin.  The pdfs can be downloaded for free at:

Ojoraptorsaurus has been mentioned on the DML before. 
Here some additional new taxa and paper with abstracts.

M. Burns and R. M. Sullivan (2011). 
A new ankylosaurid from the Upper Cretaceous Kirtland 
Formation, San Juan Basin, with comments on the diversity 
of ankylosaurids in New Mexico. 
New Mexico Museum of Natural History and Science Bulletin 
53: 169-178. 

A new, small ankylosaurid, Ahshislepelta minor, from the 
upper Campanian Kirtland Formation (Hunter Wash Member), 
San Juan Basin, New Mexico, consists of shoulder girdle 
and forelimb elements, vertebral fragments, and numerous 
osteoderms. Ahshislepelta minor differs from other 
ankylosaurids on the basis of a prominent dorsolateral 
overhang of the acromion and its osteoderm texture. It 
ranks as one of the most complete ankylosaur specimens 
known from New Mexico and adds to our understanding of 
ankylosaurid paleobiogeography,stratigraphy, and taxonomy.

M. Watabe, K. Tsogtbaatar and R. M. Sullivan (2011). 
A new  pachycephalosaurid from the Baynshire Formation 
(Cenomanina-Late Santonian), Gobi Desert, Mongolia.
New Mexico Museum of Natural History and Science Bulletin 

A nearly complete pachycephalosaurid frontoparietal dome, 
from the Baynshire Formation at Amtgai,southern Gobi 
Desert, Mongolia, is identified as a new taxon. 
Amtocephale gobiensis n. gen., n. sp. differs from all 
other pachycephalosaurids in a combination of features 
that include: deep supratemporal fossae; broad 
(craniocaudally) prefrontal sutural surfaces with the 
nasal; prefrontal and anterior supraorbital sutural 
surfaces lying in a single plane; short parietal 
(parietal length to the frontoparietal length is 2.44); 
the medial posterior extension the parietal sharply 
downturned and wide relative to the maximum width of the 
frontoparietal; and lacking supratemporal fenestrae. 
Amtocephale gobiensis may be the oldest known 
pachycephalosaurid as it comes from rocks that are no 
younger than late Santonian. While it may be the oldest 
known pachycephalosaurid, phylogenetic analysis 
Amtocephale gobiensis suggests relationship to the more 
derived pachycephalosaurids
R. M. Sullivan and D. Fowler (2011) 
Navajodactylus boerei, n. gen., n. sp., (Pterosauria, ?
Azhdarchidae) from the Upper Cretaceous Kirtland 
Formation (upper Campanian) of New Mexico. 
New Mexico Museum of Natural History and  Science 
Bulletin 53:393-404. 

Navajodactylus boerei gen. et sp. nov. is a new ?
azhdarchid pterosaur from the Upper Cretaceous Kirtland 
Formation (Hunter Wash Member), San Juan Basin, New 
Mexico. The holotype consists of the proximal portion of 
a right 1st wing phalanx with a fused extensor tendon 
process. Comparison to other named and unnamed pterosaurs 
indicates that the morphology of the extensor tendon 
process can be used to differentiate pterosaur taxa. 
Navajodactylus boerei is characterized by having a well-
developed extensor tendon process that covers 75%
of the proximal articulation surface of the 1st  wing 
phalanx, with a pronounced dorsal boss on the superior 
margin of the dorsal cotyle, and it has a shallow, open 
extensor tendon process saddle. The arc of metacarpal IV 
is large and occupies more than 50% of the proximal area 
of the dorsal cotyle on the extensor tendon process.
Navajodactylus boerei is a component of the Hunter Wash 
local fauna (Kirtlandian land-vertebrate age [LVA]), 
which is approximately 75 Ma (late Campanian). This age 
date is based on the stratigraphic position of the type 
locality which lies below ash 2, dated at 74.44 Ma, and 
above ash DEP, dated at 75.56 Ma. Navajodactylus boerei 
is also identified among the pterosaur material recovered 
from the the Dinosaur Park Formation, Dinosaur Provincial 
Park, Alberta, Canada. This material is late Judithian 
LVA and is dated approximately 76-75.3 Ma, an age
slightly older than the age of the holotype.


already mentioned on DML

R. M. Sullivan, S. E. Jasinski, M. P. A. Van Tomme 
A new caenagnathid Ojoraptorsaurus boerei n. gen., n. sp. 
(Dinosauria: Oviraptorsauria), from the Upper Cretaceous 
Ojo Alamo Formation (Naashoibito Member), San Juan Basin, 
New Mexico. New Mexico Museum of Natural History and 
Science Bulletin 53:418-428.

A nearly complete pair of pubes is identified as a new 
caenagnathid oviraptorosaur, Ojoraptorsaurus boerei, n. 
gen., n. sp., based on having a ?spoon-shaped? depression 
on the anterior dorsal surface of the pubic boot, an 
elongated anterior process of the pubic boot, a recessed 
enclosed pubic fossa, the distal end of the pubic shaft 
convex anteriorly, and a sub-trapezoidal pubic peduncle 
articulation surface.  Ojoraptorsaurus boerei is most
similar to ROM 43250 (previously assigned to 
Chirostenotes pergracilis Gilmore) from the Horseshoe 
Canyon Formation (upper Campanian-lower Maastrichtian) of 
Alberta, Canada, but differs from it in having a pubic 
fossa that is lower on the shaft, a trapezoidal-shaped 
articulation surface of the pubes, a shorter shaft length 
and in being more robust. ROM 43250 is placed in a new 
genus and species, Epichirostenotes curriei, that is much 
younger than
Chirostenotes pergracilis (sensu stricto), which may 
include the holotype of Macrophalangia canadensis (CMN 
8538) and a referred specimen TMP 79.20.1, all of which 
are from the Dinosaur Park Formation and predate E. 
curriei by nearly 3 million years. The holotype specimen 
of Epichirostenotes curriei (ROM 43250) differs 
morphologically from Chirostenotes pergracilis (sensu 
stricto), based on TMP 79.20.1, in features of the 
We note minor differences in the morphology of the left 
manus of the holotype of Chirostenotes pergracilis (CMN 
2367) compared to TMP 79.20.1, suggesting that these two 
may not be conspecific. Ojoraptorsaurus boerei is from 
the Naashoibito Member of the Ojo Alamo Formation, San 
Juan Basin, New Mexico, and is part of the Alamo Wash 
local fauna. This fauna is considered to be 69 Ma and 
thus is early Maastrichtian in age. Ojoraptorsaurus
boerei represents the southern-most occurrence of a 
caenagnathid in North America. It is the first and only 
known caenagnathid from New Mexico and from the lower 
Maastrichtian of North America


Other papers:
M. Burns and R. M. Sullivan (2011) 
The tail club of Nodocephalosaurus kirtlandensis 
(Dinosauria: Ankylosauridae), with a review of 
ankylosaurid tail club morphology and homology. 
New Mexico Museum of Natural History and Science Bulletin 
53: 179-186. 

Three new tail club specimens are referred to the Upper 
Cretaceous ankylosaurid Nodocephalosaurus kirtlandensis 
from the De-na-zin Member of the Kirtland Formation (San 
Juan Basin, New Mexico, USA). These incomplete specimens 
represent portions of major and minor plates of the tail 
club. The plates of Nodocephalosaurus are unique in their 
smooth surface texture when compared to the other North 
American taxa, Euoplocephalus and Ankylosaurus. However, 
they are structurally similar in overall shape to some 
specimens that are currently referred to Euoplocephalus. 
The histology and surface texture of tail club osteoderms 
do not always correlate with those of other postcranial 
osteoderms, even within individuals.

S. E. Jasinski and R. M. Sullivan (2011) 
Re-evaluation of pachycephalosaurids from the Fruitland-
Kirtland transition (Kirtlandian, late Campanian), San 
Juan Basin, New  Mexico, with a description of a new 
species of Stegoceras and a reassessment of Texascephale 
New Mexico Museum of Natural History and Science Bulletin 

Two partial pachycephalosaurid skulls, from the upper 
Fruitland and lower Kirtland formations(Upper 
Cretaceous), are recognized as belonging to a new species 
of Stegoceras Lambe, S. novomexicanum, n. sp. Stegoceras 
novomexicanum differs from the only other recognized 
species of Stegoceras (sensu Sullivan, 2003) in 
possessing: a reduced and sub-rectangular posteromedial 
extension of the parietal; parallel squamosal sutural 
surface contacts of the posteromedial extension of the 
parietal; enlarged and medially positioned supratemporal
fenestrae; and a small (adult) size. Fusion of the 
frontal and parietal in one specimen, coupled with a 
smooth dorsal surface of the frontoparietal dome, is 
consistent with an adult ontogenetic stage. Gross 
histology reveals four histomorphs, the fourth (outer-
most layer) indicates arrested growth, further attesting 
to its mature state. Stegoceras novomexicanum is known 
from, and restricted to, the upper Fruitland Formation 
(Fossil Forest Member) and lower Kirtland Formation 
(Hunter Wash  Member); the collective vertebrates from 
these contiguous strata make up the Hunter Wash local 
fauna. Contrary to previous reports, the Prenocephale (= 
Sphaerotholus)-like pachycephalosaurids are not known 
from the early Kirtlandian, but are restricted to the 
Willow Wash local fauna of the upper Kirtland Formation 
(De-na-zin Member). Stegoceras novomexicanum is 
temporally younger (Kirtlandian) than the well-known S. 
validum from the Judithian of Alberta, Canada.
A reassessment of the newly named taxon Texacephale 
langstoni demonstrates that it is not based on diagnostic 
material and, therefore, is a nomen dubium.

S. E. Jasinski, R. M. Sullivan and S. G. Lucas (2011) 
Taxonomic composition of the Alamo Wash local fauna from 
the Upper Cretaceous Ojo Alamo Formation (Naashoibito 
Member) San Juan Basin, New Mexico. 
New Mexico Museum of Natural History and Science Bulletin 

The vertebrate fauna from the Upper Cretaceous 
Naashoibito Member of the Ojo Alamo Formation 
(Sandstone), also known as the Alamo Wash local fauna 
(AWlf), has been the focus of intense collecting for over 
20 years in order to clarify the biostratigraphic 
occurrences of taxa within this unit. Previously, some 
vertebrate taxa from the underlying De-na-zin Member of 
the Kirtland Formation, which lies unconformably below 
the Naashoibito Member, were mistakenly included in the 
original definition of the fauna. Therefore, the 
taxonomic composition of the Alamo Wash local fauna has 
not been properly assessed until now. The Alamo Wash 
local fauna consists of a variety of vertebrate taxa, 
including fish, a salamander, turtles, crocodylians, 
dinosaurs, and mammals. The fossil vertebrates from the 
AWFL include a few fishes: Myledaphus sp., ?Squatirhina 
sp., Lepisosteidae indet. and an indeterminate 
osteichthyan. There is an indeterminate ?
Batrachosauroididae and a few turtles, including the 
pleurosternid Compsemys sp., an indeterminate baenid, the 
questionable kinosternoid Hoplochelys sp., an 
indeterminate adocid, the nanhsiungchelyid ?Basilemys 
sp., the trionychid Plastomenus sp. as well as an 
indeterminate trionychid. The teiid lizards ?Chamops sp. 
and Peneteius sp. have been documented by others, but not 
verified by us, so we tentatively accept their presence. 
Crocodylians include cf. Brachychampsa sp. and 
indeterminate crocodylian material. Dinosaurs are 
represented by numerous theropods, including the 
problematic coelurosaurian Ricardoestesia sp., the 
tyrannosaurid cf. Tyrannosaurus sp., indeterminate 
ornithomimids, the caenagnathid Ojoraptorsaurus boerei, 
an indeterminate troodontid, and a new unnamed 
dromaeosaurid. Sauropods are represented by the 
titanosaur Alamosaurus sanjuanensis. Ankylosaurs include 
the nodosaurid Glyptodontopelta mimus and an 
indeterminate ankylosaurid that is close to 
Euoplocephalus. Hadrosaurs include an indeterminate 
lambeosaurin that is close to Corythosaurus and 
Hypacrosaurus as well as indeterminate hadrosaurines. The 
chasmosaurine Ojoceratops fowleri is the only diagnostic 
ceratopsian known, but other ceratopsid material suggests 
other ceratopsid taxa are present. Mammals include the 
neoplagiaulacid Mesodma formosa, the eucosmodontid cf. 
Essonodon sp., the taeniolabidid cf. Meniscoessus sp., an 
indeterminate pediomyid, the alphadontin Alphadon marshi, 
and the glasbiid aff. Glasbius sp.  Taxa that have been 
removed, and are no longer considered part of the AWlf, 
include the iconic lambeosaurine Parasaurolophus tubicen 
and the chasmosaurine Pentaceratops, together with 
numerous other dinosaurs and non-mammalian vertebrates.
The Alamo Wash local fauna is dated to approximately 69 
Ma based on correlation of Alamosaurus sanjuanensis to 
its occurrence in the Big Bend region of Texas, where it 
has been dated radioisotopically. This places the AWlf 
temporally before the Lancian LVA in the late-early 
Maastrichtian to earliest late Maastrichtian 
(late ?Edmontonian?).
There is no definitive evidence to support a Lancian or a 
Paleocene age for this vertebrate fauna.

R. M. Sullivan, S. E. Jasinski, M. Guenther and S. G. 
Lucas (2011) 
The first lambeosaurin (Dinosauria, Hadrosauridae, 
Lambeosaurinae) from the Upper Cretaceous Ojo Alamo 
Formation (Naashoibito Member), San Juan Basin, New 
New Mexico Museum of Natural History and Science Bulletin 

A nearly complete robust left humerus (SMP VP-2263) and 
right jugal (SMP VP-1534) belonging to a lambeosaurin 
lambeosaurine (= Lambeosaurus + (Corythosaurus + 
Hypacrosaurus)) dinosaur have been recovered from two 
separate localities in the Naashoibito Member (Ojo Alamo 
Formation), San Juan Basin, New Mexico. Measurements of 
the humerus are: length = 550 mm; deltopectoral crest 
length = 260 mm; deltopectoral width = 135 mm. The robust 
morphology and measurements of the humerus confirm it 
pertains to a member of the lambeosaurin clade, which we 
formally establish. The jugal has a maximum rostrocaudal 
length of 255 mm and a shape that is inconsistent with 
the jugals of all species of Parasaurolophus. These 
specimens, which are very similar to the humerus and 
jugal of Corythosaurus and Hypacrosaurus, constitute 
definite records of lambeosaurines from the Naashoibito 
Member, despite previous erroneous reports of the 
occurrence of Parasaurolophus tubicen from this horizon. 
The putative hadrosaurine, NMMNH P-19147, is re-
interpreted as a lambeosaurin lambeosaurine, based 
primarily on the morphology of the pubis. Recovery of 
additional lambeosaurine material in the Naashoibito 
Member lends further support to a pre-Lancian age for 
this interval and for the Alamo Wash local fauna.

S. G. Lucas, R. M. Sullivan, S. E. Jasinski and T. L. 
Ford (2011) 
Hadrosaur footprints from the Upper Cretaceous Fruitland 
Formation, San Juan Basin, New Mexico, and the 
ichnotaxonomy of large ornithopod footprints. 
New Mexico Museum of Natural History and Science Bulletin 

Several sandstone casts of dinosaur footprints, 
identified as the ichnogenus Caririchnium, have been 
recovered from the lower part of the Fossil Forest 
Member, Fruitland Formation, San Juan Basin, New Mexico. 
The footprints, which were made by a large hadrosaur, are 
tridactyl, have broad, rounded heel imprints, and thick 
toes that terminate in short, narrow claw tips with the 
largest specimens as much as 940 mm long. Skeletal 
remains of large hadrosaurs are also known from the 
Fruitland Formation, so these dinosaurs are now known by 
both bones and footprints. A reconsideration of the 
ichnotaxonomy of large ornithopod footprints suggests 
that only two ichnogenera may be valid: Caririchnium (= 
Hadrosauropodus) and Amblydactylus (= Iguanodontipus).

R. M. Sullivan, S. G. Lucas (2011).
Charles Hazelius Sternberg and his San Juan Basin 
Cretaceous dinosaur collections: Correspondence and 
photographs (1920-1925). 
New Mexico Museum of Natural History and Science Bulletin 
[NOTE: Because of the large size of this file the PDF in 
two parts (pt. 1) and (pt. 2)]


R. M. Sullivan, S. G. Lucas and S. E. Jasinsk i(2011). 
The humerus of a hatchling lambeosaurine (Dinosauria: 
Hadrosauridae) referable to cf. Parasaurolophus tubicen 
from the Upper Cretaceous Kirtland Formation (De-na-zin 
Member), San Juan Basin, New Mexico. 
New Mexico Museum of Natural History and Science Bulletin 

A small left humerus of a lambeosaurine (Hadrosauridae), 
measuring 41 mm in length, is identified as a hatchling 
individual that probably belongs to the taxon 
Parasaurolophus tubicen. The specimen was discovered in 
the Kirtland Formation (De-na-zin Member), in the same 
stratigraphic horizon, and close to the locality, where 
the skull of Parasaurolophus tubicen (NMMNH P-25100) was 
found. This is the first recognized hatchling dinosaur 
from the Upper Cretaceous of New Mexico and it is the 
first known to be referable to P. tubicen. The presence of
this hatchling suggests that the nearby area probably was 
a breeding ground for these lambeosaurine dinosaurs.
R. M. Sullivan, S. G. Lucas, S. E. Jasinski and D. H. 
Tanke (2011). 
An unusual neural spine osteopathy of a chasmosaurine 
(Dinosauria: Ceratopsidae) from the Upper Cretaceous 
Kirtland Formation (Hunter Wash Member), San Juan Basin, 
New Mexico. New Mexico Museum of Natural History and 
Science Bulletin 53:484-488. 

An unusual paleopathology, in the form of an irregular-
shaped bony plate that is fused to, and is part of, the 
fused neural spine complex, is the first of its kind to 
be described for a ceratopsid dinosaur. This pathology is 
a bony mass composed of a network of fused ossified 
tendons and secondary bone deposited in a rather thin 
plate that extends out from the neural spine centered 
over the 5th  and 6th sacral vertebrae. The etiology of 
this unusual pathology is unknown. We interpret this 
paleopathology as the possible result of a bite, or bites,
to the back of the chasmosaurine, although there is no 
direct evidence of this. The plate is inferred to have 
been within the compact dermal layer of the 
chasmosaurine?s sacrum.