关键词: 新沂河, 淮河下游, 晚更新世动物群, 扬子鳄, 河套大角鹿

Abstract:

As one of the few reported Pleistocene faunal assemblages from the lower Huaihe River Region, this taxonomic study sheds new light on the biostratigraphy of the Zhangshan fauna. Zhangshan is a fossil locality in the lower Huaihe River region, located where the modern climatic transition area lies between North and South China. This fossil locality was accidentally found in the 1950’s during the Xinyihe River construction project, when a few poorly preserved fragments were unearthed. Recently, more identifiable specimens were collected during a test excavation and these are the focus of this study. The material originates from a fossil layer around 0.4 m thick, composed of greyish yellow fine sands and rich with calcic concretions.The following taxa have been identified: Turtles, Alligator cf. sinensis, Palaeoloxodon huaihoensis, Equus hemionus, Stephanorhinus kirchbergensis, Sus lydekkeri, Sinomegaceros ordosianus, Cervus (Sika) grayi and Bison priscus. The identified species allow for a re-assessment of the current record, including specimens of Alligator cf. sinensis that represents the northernmost record of this species during Pleistocene and remains of Bison priscus, which is the most southern recorded example of this taxon. The Palaeoloxodon materials were identified as P. huaihoensis, based on a lamellae number greater than P. namadicus, and of a bigger size than P. naumanni. The mandible of S. ordosianus is the only specimen with a complete cheek teeth series. Study of these Sinomegaceros materials further confirms that mandible thickness, cheek teeth length and antler size are significantly correlated in evolution; at the end of Sinomegaceros lineage, S. ordosianus has the longest cheek teeth row, the slimmest mandible, as well as more slight antler.Most of the elements of Zhangshan fauna represent extinct species, however, E. hemionus and S. ordosianus were recorded only in Late Pleistocene. Thus we can put the age of Zhangshan fauna at the early Late Pleistocene. The ecological setting of the Zhangshan fauna likely reflects a mixed habitat of swamp, forest and grassland in a relatively warm and humid climate. Zhangshan locality is also the only reported fossil assemblage studied as of yet from the Malingshan mountains, where dozens of Late Pleistocene Paleolithic sites have been discovered through surveys. Although further study is needed of the relationship between these fossils and artifacts from the site, the present research begins to elucidate the environmental background of human evolution in the Malingshan mountains.

Key words: Xinyihe River, Lower Huaihe River region, Late Pleistocene Fauna, Alligator cf. sinensis, Sinomegaceros ordosianus