记河北赤城上侏罗统-下白垩统土城子组窄足龙-巨齿龙(兽脚类恐龙)足迹组合及其古生态学意义(英文)

记述了河北省赤城县落凤沟化石点163个窄足龙足迹(Therangospodus isp.)。当该地区洪水泛滥时,同样的造迹者留下了5个游泳迹。一个异常大的足迹和一道疑似尾迹被归入巨齿龙足迹(Megalosauripus isp.)。土城子组7个主要足迹化石点表明,兽脚类的似鹬龙足迹型(Grallator morphotype)占据主导地位,这些足迹型的大小在各个足迹化石点都有着特定的范围。如果这些大小不同的足迹属于同一种造迹者,则暗示着同年龄的成员在特定年龄时会共同栖息在一起,在动物行为学上类似现生的一些蜥蜴和短吻鳄;如果这些足迹由不同的造迹者组成,则暗示着不同大小的种(主要表现在小型动物)可能拥有自己的领地,并特意避免与其他动物(特别是大型动物)相接触,在动物行为学上类似现生的肉食性哺乳动物。

THERANGOSPODUS AND MEGALOSA URIPUS TRACK ASSEMBLAGE FROM THE UPPER JURASSIC-LOWER CRETACEOUS TUCHENGZI FORMATION OF CHICHENG COUNTY, HEBEI PROVINCE, CHINA AND THEIR PALEOECOLOGICAL IMPLJCATIONS

One hundred sixty-three footprints that pertain to Therangospocus have been found in the Tuchengzi Formation at the Luofenggou track site in Chicheng County,Hebei Province,China.Five swim tracks were subsequently made by the same track makers after water submerged the region.In addition to the Therangospodus tracks,one exceptionally large theropod track and one possible trail trace are referred to Megalosauripus isp.Theropod tracks of the grallatorid morphotype predominate at this site and at six other known Tuchengzi Formation track sites ; grallatorid tracks at each of these sites are dominated by individual specimens in particular size ranges.If the tracks were made by the same species of track maker,the variation in dominant track size among sites suggests that cohabiting groups were composed mainly of members of a single age class,ethologically similar to some extant lizards and Alligator.If the tracks were instead made by different species,their size distribution (favoring smaller species) suggests that species of different sizes may have preferred discrete territories or specifically avoided close contact with other (particularly larger) species,ethologically similar to modern carnivorous mammals.