A Study On Tardigrade Fauna And Species Diversity In Wumeng Mountains

[Objective]Tardigrades,commonly known as " water bears," are a group of tiny aquatic invertebrates.Belonging to a separate phylum called Tardigrade.Most of them live in mosses,and a few live in lichens,moist soil and sea water intertidal zones.Tardigrades are known for their strong resistance to stress and cryptic phenomenon.At present,tardigrade research is active and popular in the world.The revision of tardigrade classification system is a new research focus.However,the study on the taxonomy of tardigrades in China is relatively slow,with only about 230 species recorded nationwide.In this paper,we selected Wumeng Mountains,a blank area of Chinese tardigrade research,as the research area,to investigate the Tardigrade fauna in Wumeng Mountains,describe the new species and new record species in China,and compare and analyze the mitochondrial gene fragments(COI,18S rRNA)of the new species.On this basis,the differences in the composition of the tardigrade fauna among the sampling points in the Wumeng Mountains and the causes of their formation were explored.[Methods]1.Combining the topographic characteristics and forest coverage of the Wumeng Mountains,6 sample areas(Cuifeng Mountain,Meihua Mountain,Yushe National Forest Park,Niangniang Mountain,Baima Mountain and Baniwo Mountain)were selected for moss collection.Then Tardigrade was extracted,photographed,measured,identified.2.Analyze the statistical dominance of tardigrade animal species.3.Four kinds of diversity indexes are used:Shannon-Wiener diversity index,Simpson dominance index,Pielou uniformity index and Margalef species richness index to describe the diversity of tardigrade animals.4.Community similarity index(cj)was used to compare the community similarity of 6 sampling sites.5.For the new species identified from morphology,molecular markers(18S rRNA and COI)were used for further identification and verification.[Results]1.449 mosses were collected in the Wumeng Mountain area,and a total of 2063 tardigrade animals were extracted.Including 30 species,they belong to 2 classes(Heterotardigrada and Eutardigrada),2orders(Echiniscidae and Apochela),6 families(Echiniscidae?Milnesiidae?Hypsibiidae?Dorysohybiidae?Iphorohybiidae).2.Among the tardigrade animals found in Wumeng Mountain,there are 1 dominant group,Mac.wumengensis sp.nov;14 common groups,Bry.wumengshanensis sp.nov?Co.lobatus?P.chengi?P.dabieshanensis sp nov?Mil.swansoni?Dip.chilenense?Iso.coulsoni?Dor.bainiensis?Dor.barbarae?Dor.huangguoshuensis?Mac.shonaicus?Mac.sp.1?Mac.sp.2 and Para.Magdalenae.3.Among the 30 species identified,more than two-thirds are found in the middle altitude,and 22 species of tardigrades are distributed from 1400m to 1700m.4.Four diversity indices(H,D,DMa,E)were calculated based on the meaning of biological a-diversity.The results showed that the species diversity of tardigrade communities was different at different sampling sites in Wumeng Mountain.5.The 18S rRNA and COI sequences of two new species Doryphoribius bainiensis sp.nov and Macrobiotus wumengensis sp.nov were successfully sequenced and uploaded to GenBank.[Conclusion]There were significant differences in the number of tardigrade species and the total number of individuals in the six sampling sites,which were closely related to the elevation gradient of the sampling sites and the plant species and coverage rate.In terms of the distribution of tardigrades at different altitudes,the species number and species richness in the region between 1400m and 1800m,that is,in the middle altitude region,are relatively large,which may conform to the mid-domain effect pattern,but it needs to establish a model for verification.