Zarafasaura and other marine reptile stuff

[bh480@scn.org]

From: Ben Creisler
bh480@scn.org

Here are some new or recent Mesozoic marine reptile 
papers, including ones dating back a few months. (Sorry 
for not fixing all the minor style inconsistencies from 
using cut-and-paste from various sources.)

Peggy Vincent , Nathalie Bardet,  Xabier Pereda 
Suberbiola,  Baadi Bouya,  Mbarek Amaghzaz,  and Said 
Meslouh (2010). 
Zarafasaura oceanis, a new elasmosaurid (Reptilia: 
Sauropterygia) from the Maastrichtian Phosphates of 
Morocco and the palaeobiogeography of latest Cretaceous 
plesiosaurs. 
Gondwana Research (advance online publication)

Though the Maastrichtian Phosphates of Morocco have 
yielded very rich marine vertebrate assemblages, 
plesiosaurs remain very scarce in these strata. The only 
hitherto recognized taxon was Plesiosaurus mauritanicus 
Arambourg, 1952, regarded here as a nomem dubium. Here we 
describe a new genus and species of elasmosaurid 
plesiosaur, Zarafasaura oceanis, which represents the 
first valid elasmosaurid plesiosaur described from the 
latest Cretaceous of Africa, and the second one from this 
continent. A phylogenetic analysis of plesiosauroids 
indicates that Zarafasaura oceanis has close affinities 
with elasmosaurids from the Late Cretaceous of North 
America and Japan. Among its distinctive suite of 
characters, the general shape and organisation of its 
squamosal and palate are unique among elasmosaurids. This 
new taxon completes our understanding of Late Cretaceous 
plesiosaur palaeobiodiversity and palaeobiogeography, and 
shows that Maastrichtian plesiosaurs were characterized 
by a quite high degree of endemism. They were also highly 
diversified and distributed worldwide, which supports the 
hypothesis of a catastrophic extinction of plesiosaurs at 
the K/T boundary.


CHEN Xiao-hong and CHENG Long, 2010.
A NEW SPECIES OF MIXOSAURUS (REPTILIA: ICHTHYOSAURIA) 
FROM THE MIDDLE TRIASSIC OF PU'AN, GUIZHOU, CHINA.
Acta Palaeontologica Sinica 2010 (2): 251-260.

The marine reptile assemblage in the Middle Triassic 
Guanling Formation of Qingshan-Xindian area, Pu'an 
County, including Sauropterygia, Protorosauria and 
Ichthyosauria, is very similar to that of the Panxian 
Fauna of Yangjian area, Pan-xian County, Guizhou 
Province. A well-preserved mixosaur specimen was 
collected from the Upper part of the Guanling Formation 
in Xindian town in recent field work. A new species 
Mixosaurus xindianensis sp. nov. was erected by detailed 
description. It is very important to the phylogeny of 
Mixosauria.The systematic paleontology and diagnosis are 
as following.

http://en.cnki.com.cn/Article_en/CJFDTotal-
GSWX201002008.htm


Elisabeth Einarsson; Johan lindgren; Benjamin P. Kear; 
Mikael Siverson, 2010.
Mosasaur bite marks on a plesiosaur propodial from the 
Campanian (Late Cretaceous) of southern Sweden.
GFF 132 (2): 1

Although plesiosaurs and mosasaurs co-existed for about 
35 million years at the end of the Cretaceous, the fossil 
record documenting interactions between these two groups 
of marine reptiles is meagre. The discovery of deeply 
incised scars on a limb bone of an immature polycotylid 
plesiosaur from the latest early Campanian (in the 
European two-fold division of the Campanian Stage) of the 
Kristianstad Basin, southern Sweden, is thus significant 
because it represents a rare example of predation or 
scavenging on an immature polycotylid plesiosaur by a 
large mosasaur.    

Peggy Vincent, 2010.
A juvenile plesiosaur specimen from the Lower Jurassic of 
Holzmaden, Germany. 
PALAEONTOGRAPHICA ABTEILUNG A-PALAOZOOLOGIE-
STRATIGRAPHIE    291 (1-2): 45-61.

A subcomplete plesiosaur skeleton (SMNS 51141) from the 
famous locality of Holzmaden (Posidonia Shale, Lower 
Toarcian of the Baden-Wurttemberg, south-western Germany) 
is described. The skeleton, showing a mosaic of 
plesiosauroid and pliosauroid characters occasions some 
difficulties in its systematic assignment, but SMNS 51141 
most likely represents a new species. It corresponds to 
one of the most complete and ontogenetically youngest 
plesiosaurs known from the Lower Jurassic and provides 
valuable new information on plesiosaur ontogenetic 
development: this has implications for the understanding 
of cranial suture ossification and the postcranial 
ontogenetic pattern. 

A. S. SMITH and P. VINCENT, 2010. 
A new genus of pliosaur (Reptilia: Sauropterygia) from 
the Lower Jurassic of Holzmaden, Germany. 
Palaeontology, 53: 1049?1063. doi: 10.1111/j.1475-
4983.2010.00975.

The exquisitely preserved holotype of the 
pliosaur ?Rhomaleosaurus?victor (SMNS 12478) is described 
from the Toarcian Posidonien-Schiefer (Upper Lias, Lower 
Jurassic) of Holzmaden (Baden-Württemberg), Germany. The 
specimen presents a novel combination of synapomorphies 
and unique morphometric proportions separating it from 
Rhomaleosaurus sensu stricto and warranting the erection 
of a new genus, Meyerasaurus gen. nov. Historically, the 
name ?Thaumatosaurus? has been interchangeable with 
Rhomaleosaurus and is frequently associated with SMNS 
12478 in the literature. However, this is an invalid 
taxon and cannot be reinstated. The anatomy of 
Meyerasaurus victor is compared in detail with other 
pliosaurs, and its taxonomic affinity is reviewed. M. 
victor belongs to the family Rhomaleosauridae and shares 
several anatomical characters with Rhomaleosaurus 
including a short and robust premaxillary rostrum (length-
to-width ratio c. 1.0), parallel premaxilla?maxilla 
sutures anterior to the nares, vomers contacting the 
maxillae posterior to the internal nares, and c. 28 
cervical vertebrae minus the atlas?axis. The known 
geographical distribution of Rhomaleosaurus, which 
previously extended across the German and English 
palaeobiogeographical zones, is reduced to the English 
zone as a consequence of the referral of SMNS 12478 to a 
new genus. This is significant because it contributes to 
an ongoing trend of increasing generic separation between 
the German and English zones, while increasing the 
generic diversity within the German zone itself.

A. G. Sennikov and M. S. Arkhangelsky, 2010.
On a typical Jurassic sauropterygian from the Upper 
Triassic of Wilczek Land (Franz Josef Land, Arctic 
Russia). 
Paleontological Journal 44 (5): 567-572.
A new elasmosaurid genus and species, Alexeyisaurus 
karnoushenkoi, from the Lower-Middle Norian (Wilczek 
Formation) of the Upper Triassic of the island of Wilczek 
Land (Franz Josef Land) is described based on an 
incomplete skeleton. The new form combines characters of 
typical late plesiosaurs and structural features unique 
to this form. It is probably the earliest representative 
of typical late sauropterygians (plesiosaurs). 

Patrick S. Druckenmiller and Erin E. Maxwell, 2010.
A new Lower Cretaceous (lower Albian) ichthyosaur genus 
from the Clearwater Formation, Alberta, Canada.
Canadian Journal of Earth Sciences 47(8): 1037?1053 
(2010)  |  doi:10.1139/E10-028  

A new, articulated skeleton of an ichthyosaur from the 
Lower Cretaceous (lower Albian) Wabiskaw Member of the 
Clearwater Formation near Fort McMurray, Alberta, is the 
most complete and stratigraphically oldest known 
ichthyosaur from the Cretaceous of North America and 
represents a new genus and species of ophthalmosaurian, 
Athabascasaurus bitumineus. The specimen consists of a 
nearly complete, dorsoventrally compressed skull, a 
complete and articulated presacral and partial caudal 
vertebral series, portions of the right pectoral girdle, 
and the right pelvic girdle and femur. The new taxon is 
characterized by the lack of a robust supranarial process 
of the premaxilla, an elongate maxilla that has its 
tallest point (in lateral view) posterior to the external 
naris, a wide postorbital region, the presence of a 
rectangular squamosal, an angular with greater lateral 
exposure on the posterior jaw ramus than the surangular, 
a dentition with extremely light enameled ridges, and a 
reduced presacral count of 42 vertebrae. The first 
species-level phylogenetic analysis of Ophthalmosauria 
reveals that Athabascasaurus is neither the sister taxon 
of, nor nests within Platypterygius, a geographically 
widespread, geologically long-lived, and taxonomically 
problematic genus. Athabascasaurus adds important new 
data on the morphology of Cretaceous ichthyosaurs and 
expands our knowledge of the palaeoecology and marine 
tetrapod diversity of the early Albian Boreal Sea.

Peggy VINCENT and Philippe TAQUET, 2010. 
A plesiosaur specimen from the Lias of Lyme Regis: the 
second ever discovered plesiosaur by Mary Anning .
Geodiversitas 32 (3): 377-390, 2010

A historical specimen of plesiosaur, discovered by Mary 
Anning and kept in the Muséum national d?Histoire 
naturelle, Paris, under the number MNHN A. C. 8592 is 
here described. Discovered in 1824 by the first 
palaeontologist woman, Mary Anning, the specimen was sold 
by her to Constant Prévost who took it to Paris. The 
specimen is the second ever discovered plesiosaur and is 
here described for the fi rst time even though it was fi 
gured by Cuvier (1825). 
The specimen is preserved in articulation and retained 
almost the entire postcranium but lacks the skull and 
most part of the neck. It preserves 56 vertebrae, most of 
the pectoral and pelvic girdles and most of the limbs. It 
was referred to  Plesiosaurus dolichodeirus  by Storrs 
(1997). Comparison with other specimens of  Plesiosaurus 
dolichodeirus  indicates that MNHN A. C. 8592 is an adult 
of advanced age. It reveals some unique features that may 
be attributed to ontogenetical and/or intraspecific 
variations. A better understanding of these variations 
among several individuals of the same species may help to 
clarify the problematic taxonomy and phylogeny of 
plesiosaurs.