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Tetrapod track record in China reviewed
From: Ben Creisler
A new paper:
Martin G. Lockley, Li Jianjun, L Rihui, Masaki Matsukawa, Jerald D.
Harris & Xing Lida (2013)
A Review of the Tetrapod Track Record in China, with Special Reference
to Type Ichnospecies: Implications for Ichnotaxonomy and Paleobiology.
Acta Geologica Sinica - English Edition 87(1): 1–20
“Splitting” and “lumping” are perpetual problems in vertebrate,
especially dinosaur, ichnotaxonomy. Chinese dinosaur ichnotaxonomy,
which began in 1940, provides a series of interesting case studies,
highlighting the dual problems of historical and dubious
ichnotaxonomy. Chinese Mesozoic tetrapod track types have been placed
into 63 ichnospecies (one Triassic, 28 Jurassic, and 34 Cretaceous),
exclusive of other, non-type ichnospecies or ichnotaxa identified from
China. Fifty-two (~83%) of these 63 tetrapod ichnospecies were placed
in monospecific ichnogenera. At the ichnogenus level, we prune—either
by recognizing nomina dubia or by synonymy—17 from the list of 53
dinosaurian ichnogenera (a 32% reduction), leaving 36 ichnotaxa that
we consider valid. Most of the cuts affect Jurassic theropod
ichnotaxa, which are reduced from 23 to only nine because most
ichnogenera are subjective junior synonyms of Grallator and Eubrontes.
Fewer Chinese Cretaceous ichnotaxa (only six of 21 ichnogenera) are
obvious nomina dubia or subjective synonyms, suggesting greater east
Asian endemism during this time. Because ichnospecies differences are
subtle, we provisionally retain ichnospecies as valid pending detailed
comparative analyses of congeneric ichnospecies. This synthesis is
long overdue and is necessary to address problems of historical and
provincial ichnotaxonomy, which severely hamper comparisons of
tetrapod ichnofaunas in space and time.