江苏宿迁嶂山地点晚更新世脊椎动物化石

A report on the Late Pleistocene vertebrate fossils from the Zhangshan locality,Suqian,Jiangsu Province

嶂山化石地点位于淮河下游、马陵山南端的人工河——新沂河的河床上。该化石点最早报道于1953年,是淮河下游为数不多的更新世化石点之一。本文报道了嶂山化石点近年新出土的一批动物化石,动物群包括:龟鳖类、扬子鳄(相似种)、虎、淮河古菱齿象、蒙古野驴、梅氏犀、李氏野猪、河套大角鹿、葛氏斑鹿和草原野牛。嶂山的扬子鳄(相似种)是该物种在更新世化石记录中分布最北的,而草原野牛则是该物种最靠南的化石记录。嶂山的古菱齿象被归入淮河古菱齿象,因其齿板数多于纳玛古菱齿象,而牙齿尺寸大于诺氏古菱齿象。嶂山河套大角鹿的下颌提供了该物种仅有的下颊齿列长度数据,证明晚更新世的河套大角鹿具有相对弱的角枝、纤细的下颌和延长的齿列,支持了中国大角鹿属(Sinomegaceros)在角枝粗壮度、下颌肿厚度和齿列长度之间的演化关联性。嶂山动物群中蒙古野驴、河套大角鹿是典型的晚更新世物种,且成员多为绝灭种,推断年代很可能为晚更新世的早段。嶂山动物群组合反映了相对温暖湿润的气候,显示当时的骆马湖一带兼有湿地、森林和草地。嶂山化石点也为马陵山地区旧石器遗存的相关研究提供了新的生物地层学参照。

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 reassessment 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.