Data di Pubblicazione:
2014
Citazione:
A new specimen ofNothosaurus youngifrom the Middle Triassic of Guizhou, China / C. Ji, D. Jiang, O. Rieppel, R. Motani, A. Tintori, Z. Sun. - In: JOURNAL OF VERTEBRATE PALEONTOLOGY. - ISSN 0272-4634. - 34:2(2014 Mar), pp. 465-470. [10.1080/02724634.2013.808204]
Abstract:
The Xingyi Fauna has been known widely for yielding abundant specimens of the pachypleurosaur sauropterygian Keichousaurus hui, the first Triassic marine reptile described from
China (Young, 1958). Later stratigraphic studies placed it within
the Zhuganpo Member of the Falang Formation (latest Ladinian,
Middle Triassic) that is exposed across a wide area ranging from
Dingxiao and Wusha (Xingyi, Guizhou Province) to Luoping and
Fuyuan (Yunnan Province) (Li and Jin, 2003). Despite the exten-
sive exposure of this unit, K. hui remained the only tetrapod from
this fauna until the end of the last century, when limited progress
was made in both taxonomic and stratigraphic studies. The situ-
ation changed during the last decade when a significant quantity
of K. hui material was described in detail, in addition to eight
new taxa of Triassic marine reptiles, i.e., Lariosaurus xingyiensis,
Nothosaurus youngi, Tanystropheus sp., Yunguisaurus liae, An-
shunsaurus wushaensis, Macrocnemus fuyuanensis, Glyphoderma
kangi, and Qianxisaurus chajiangensis (Li et al., 2002, 2007; Li
and Rieppel, 2004; Cheng et al., 2006, 2012; Rieppel et al., 2006,
2008; Zhao et al., 2008a, 2008b). However, precise stratigraphic
and locality information still remained unknown for these new
taxa, as well as the Xingyi Fauna at large.
Nothosaurus youngi was named by Li and Rieppel (2004)
based on an incomplete skeleton from the Xingyi Fauna. It was
characterized by the combination of the following features: pineal
foramen located in a trough near the posterior end of the pari-
etal, and the longitudinal diameter of the upper temporal fenes-
tra nearly twice of that of the orbit. The postcranial osteology was
only briefly described from the incompletely preserved skeleton,
including the vertebrae and ribs, parts of the pelvic girdle, and a
forelimb. Most of the pectoral girdle was overlapped by the gas-
tralia, and no information was available for the hind limb.
Here, we describe a new specimen of Nothosaurus youngi that
we recovered during an excavation of the fossiliferous levels of
the Zhuganpo Member at Nimaigu village in the Wusha Town,
Xingyi, Guizhou Province, South China, in 2011. The excavation
provided us with precise knowledge of the locality and strati-
graphic level of Xingyi Fauna for the first time (see below). The
specimen is more complete than the holotype and provides new
information on the postcranial osteology of N. youngi, which was
not known when the species was erected.
Tipologia IRIS:
01 - Articolo su periodico
Elenco autori:
C. Ji, D. Jiang, O. Rieppel, R. Motani, A. Tintori, Z. Sun
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