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Dakotadon lakotaensis, Dollodon bampingi and Pteraichnus koreanensis
have been finally published in the last issue (april) of Cretaceous
Research. Here are the abstracts of both papers:
Gregory S. Paul. 2008. A revised taxonomy of the iguanodont dinosaur
genera and species. Cretaceous Research, 29(2), 192-216.
Criteria for designating dinosaur genera are inconsistent; some very
similar species are highly split at the generic level, other
anatomically disparate species are united at the same rank. Since the
mid-1800s the classic genus Iguanodon has become a taxonomic grab-bag
containing species spanning most of the Early Cretaceous of the
northern hemisphere. Recently the genus was radically redesignated
when the type was shifted from nondiagnostic English Valanginian teeth
to a complete skull and skeleton of the heavily built,
semi-quadrupedal I. bernissartensis from much younger Belgian
sediments, even though the latter is very different in form from the
gracile skeletal remains described by Mantell. Currently, iguanodont
remains from Europe are usually assigned to either robust I.
bernissartensis or gracile I. atherfieldensis, regardless of location
or stage. A stratigraphic analysis is combined with a character census
that shows the European iguanodonts are markedly more morphologically
divergent than other dinosaur genera, and some appear phylogenetically
more derived than others. Two new genera and a new species have been
or are named for the gracile iguanodonts of the Wealden Supergroup;
strongly bipedal Mantellisaurus atherfieldensis Paul (2006. Turning
the old into the new: a separate genus for the gracile iguanodont from
the Wealden of England. In: Carpenter, K. (Ed.), Horns and Beaks:
Ceratopsian and Ornithopod Dinosaurs. Indiana University Press,
Bloomington, pp. 69?77) (holotype BMNH R5764) which possesses a
camptosaur-like ilial shape, and the long snouted, long bodied, small
hipped, semi-bipedal Dollodon bampingi gen. nov. sp. nov. (holotype
IRSNB 1551) which has a shallow ilium. Insufficiently diagnostic I.
hoggii is removed from the earlier Camptosaurus. Poorly described I.
dawsoni, I. fittoni and I. hollingtoniensis are removed from the much
later and more derived Iguanodon and considered Ornithopoda incertae
sedis pending redescription. The synonymy of I. fittoni and I.
hollingtoniensis has not been confirmed. A set of remains of similar
age to I. fittoniand I. hollingtoniensis appear to combine a
specialized, elongate dentary with massive arms: it either belongs to
one of the contemporary taxa, or is a new, unnamed taxon. There has
recently been a tendency to consider iguanodonts spatially remote from
I. bernissartensis to be members of or very similar to the type
species, but reanalysis finds that I. orientalis is not a junior
synonym of I. bernissartensis and is a nomen dubium, and that basal I.
lakotaensis is not a member of Iguanodon and accordingly is assigned
the new genus Dakotadon gen. nov. (holotype SDSM 8656). Dakotadon is
probably basal to Iguanodon and not an iguanodontoid. The higher
taxonomy of iguanodontoids is confused due to phylogenetic problems,
and inconsistent definitions of the Iguanodontidae (which as currently
defined appears to be limited to Iguanodon) and Hadrosauroidea.
Mantellisaurus and especially Dollodon, for instance, are probably
more derived than Iguanodon: they may be hadrosauroids depending on
which phylogenetic definition of the term is preferred.
Keywords: Iguanodon; Iguanodontia; Ornithopoda; Dinosaurs; Europe;
Wealden Supergroup; Early Cretaceous
Yuong-Nam Lee, Hang-Jae Lee, Junchang Lu, Yoshitsugu Kobayashi. 2008.
New pterosaur tracks from the Hasandong Formation (Lower Cretaceous)
of Hadong County, South Korea. Cretaceous Research, 29(2), 345-353.
In 2004, fifty new pterosaur tracks were discovered in the Hasandong
Formation (Lower Cretaceous), South Korea. They are preserved as
natural casts on the surface of an isolated dark grey mudstone block
(70 × 50 cm). Manus and pes imprints are very small, averaging 25.6 mm
and 25.7 mm long, respectively. The manus imprints (N = 25) are
tridactyl and digit I, II, III are strongly asymmetric. Fully
plantigrade pes imprints (N = 25) were left by elongate metatarsals
with short four digits (the ratio of digit to whole pes length is
2.6). There is no trace of the 5th phalanx of the pes. As these
features clearly distinguish the Hadong tracks from the type species
of the ichnogenus Pteraichnus, we assign them to a new species,
Pteraichnus koreanensis. They are stratigraphically the oldest
pterosaur tracks in Korea and are distinguished by size and morphology
from the two pterosaur ichnotaxa, Haenamichnus uhangriensis and
Pteraichnus isp., previously reported from the Uhangri and Haman
formations. Pteraichnus koreanensis is the smallest pterosaur track
currently reported from Asia.
Keywords: Pterosaur tracks; Pteraichnus koreanensis; Early Cretaceous;
Hasandong Formation; South Korea
Jose Ignacio Ruiz-Omeñaca
Museo del Jurásico de Asturias (MUJA)
E-33328 Colunga, Spain