Discovery of Early Triassic microconchids in shallow-water clastic facies from western Guizhou Province and its palaeoecological significance
Microconchids are a group of aquatic phoronid animals mainly in fixation lifestyle.They are widely dis-tributed in the strata from the Ordovician to Jurassic.This study reports abundant calcareous microconchid fossils and their molds from the mudstone layers of the Lower Triassic Yelang Formation at the Bozhou section in Zunyi and the Liuzhi section in Liupanshui,Guizhou Province.These fossils are excellently preserved with unique microcrystalline structures consisting of micro-lamellar layers of parallel fibers.In this paper,a total of four species in two genera be-longing to two microconchid families are identified.This is the first discovery of microconchids in the Early Triassic shallow-water clastic facies from South China.Palaeoecologically,this microconchid community shows low diversity and high abundance,typical characteristics of an ecological disaster taxon with strong adaptability to the harsh marine environment of the Early Triassic.
Biological recoveryecological analysisdisaster taxonYelang FormationSouth China