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esembles those of Cladodoides and Tamiobatis,<br />
especially in the proportions of its otic<br />
region, the presence of an extensive dorsum<br />
sellae, and the arrangement of canals for major<br />
nerves and blood vessels. The internal<br />
structure of the occipital region is remarkably<br />
like that found in Tamiobatis braincases in<br />
having a prominent subnotochordal septum<br />
and paired subnotochordal and paroccipital<br />
chambers. Cladodus is no longer regarded as a<br />
nomen dubium, since only a few species<br />
founded on isolated teeth are now retained in<br />
the re-diagnosed genus, and one of these<br />
(C. elegans) is now associated with skeletal<br />
remains. The best systematic placement for<br />
Cladodus sensu stricto is among the Ctenacanthiformes<br />
or even the Ctenacanthidae.<br />
Cladodus may be a synonym of Ctenacanthus,<br />
but this cannot be confirmed with the available<br />
material.<br />
2008010271<br />
Spitsbergen 早 泥 盆 世 Gigantaspis = The<br />
genus Gigantaspis heintz, 1962 (Vertebrata,<br />
Heterostraci) from the lower Devonian of<br />
Spitsbergen. ( 英 文 ). Pernegre V; Goujet D.<br />
Palaeontology, 2007, 50(2): 323-346<br />
Material collected in 1969 by the CNRS-<br />
MNHN expedition to Spitsbergen includes a<br />
new species of Gigantaspis, G. minima, which<br />
is the smallest known species of this genus.<br />
The revision of Gigantaspis leads to the inclusion<br />
of Zascinaspis laticephala Blieck and<br />
Goujet in this genus. The phylogenetic analysis<br />
presented herein suggests that Gigantaspis<br />
is close to Zascinaspis, as suggested by Blieck.<br />
Moreover, it is also close to generalized representatives<br />
of the Protaspididae. Their shared<br />
character states allow the definition of a possible<br />
ancestral morphotype for the Protaspididae.<br />
2008010272<br />
得 克 萨 斯 早 白 垩 世 阿 尔 布 期 Pawpaw 页 岩<br />
中 的 Anacoracid 类 = Anacoracid Sharks<br />
From The Albian (Lower Cretaceous) Pawpaw<br />
Shale of Texas. ( 英 文 ). Siverson M;<br />
Lindgren J; Kelley L S. Palaeontology, 2007,<br />
50(4): 939-950<br />
Recent collecting from the Pawpaw Shale<br />
in north-east Texas has yielded several hundred<br />
teeth of anacoracid sharks. The material<br />
allows for a much-needed revision of the Late<br />
Albian anacoracids from North America. The<br />
previously recognized Squalicorax sp., also<br />
referred to as S. volgensis in more recent publications,<br />
is a mix of two different species:<br />
S. priscoserratus sp. nov. and S. pawpawensis<br />
sp. nov. In addition to these two new species,<br />
a single tooth is assigned to S. aff.<br />
S. baharijensis. Our data indicate that anacoracids<br />
were a considerably more diverse<br />
group in the North American Cretaceous than<br />
previously thought. We attribute much of the<br />
underestimation of diversity to vague species<br />
concepts, poor preparation techniques and the<br />
associated lack of attention to certain dental<br />
features, in particular neck morphology, root<br />
surface porosity and the root's vascularization.<br />
2008010273<br />
对 存 疑 Auchenaspis 的 综 述 及 其 在<br />
Thyestidian 演 化 上 的 作 用 = A Review Of<br />
The Problematic Osteostracan Genus<br />
Auchenaspis And Its Role In Thyestidian Evolution.<br />
( 英 文 ). Sansom R. Palaeontology,<br />
2007, 50(4): 1001-1011<br />
The poorly understood osteostracan genus<br />
Auchenaspis, from the Upper Silurian of England,<br />
belongs to the thyestidians (Thyestiida),<br />
a controversial and important group that is key<br />
to the understanding of the evolution of the<br />
Osteostraci and paired pectoral fins. The two<br />
under-studied species of this genus are comprehensively<br />
reviewed using anatomical and<br />
novel statistical approaches. No reliable anatomical<br />
characters can be used to distinguish<br />
between the two species, yet discriminant<br />
analysis finds significant separation with respect<br />
to size. Potential causes of this conflict<br />
are discussed. The findings enable<br />
Auchenaspis to be considered in terms of<br />
wider thyestidian evolution and contradict<br />
previous interpretations of the genus as representing<br />
a paraphyletic taxon, whose morphology<br />
is intermediate between the general osteostracan<br />
condition and the highly derived tremataspids.<br />
2008010274<br />
西 班 牙 北 部 比 利 牛 斯 山 脉 南 部 晚 坎 潘 期 及<br />
早 马 斯 特 里 赫 特 期 ( 晚 白 垩 世 ) 的<br />
Neoselachians = Neoselachians From The<br />
Upper Campanian And Lower Maastrichtian<br />
(Upper Cretaceous) Of The Southern Pyrenees,<br />
Northern Spain. ( 英 文 ). Kriwet J; Soler-Gijón<br />
R; López-Martínez N. Palaeontology, 2007,<br />
50(5): 1051-1071<br />
Bulk sampling of upper Campanian to<br />
lower–middle Maastrichtian coastal and lagoonal<br />
deposits in five sections of the Tremp<br />
Formation in the south-central Pyrenees<br />
yielded numerous neoselachian teeth. The<br />
fauna comprises nine taxa of which three spe-<br />
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