Ediacaran Holdfasts and Their Systematics

摘要

INTRODUCTION Fossil holdfasts of soft-bodied organisms are widespread in Ediacaran (Vendian) deposits, although they have long been interpreted as casts of jelly-fish (Glaessner and Wade, 1966; Sprigg, 1949) or modes of preservation of other organisms. The fact that microbial colonies (Grazhdankin and Gerdes, 2007) and sedimentary structures (Jensen et al., 2002) can have a similar mode of preservation further complicates the problem. Hence, the holdfasts remain one of the least .studied groups of soft-bodied organisms usually neglected by the mainstream paleontology. But it is holdfasts that are usually preserved in the fossil record because of their biostratinomic position in the sediment during burial. They are also important fomining ecological habitat of the oldest macroorganisms.