Studies On Taxonomy And Species Diversity Of Ciliated Protozoa From Wetlands In Chongming Island,Shanghai

The ciliated protozoa have a high species diversity and occupy an important energy transfer hub in the aquatic micro-food web,but understandings about their biodiversity in some special habitats are very limited.Wetlands in Chongming Island,Shanghai,are important international wetlands and have high diversities of biological resources.However,researches on ciliates' diversity in these unique low-salinity tidal wetlands are still in their infancies.Consideration about this situation,we adopted the direct water sampling method to collect one-year ciliated protozoa in Dongtan and Northern Wetland in Chongming Island,Shanghai,and carried out an investigation on the morphology of ciliates from the year of 2015,with a view to further clarifying a lot of confusion in taxonomy,enriching the biodiversity of ciliated protozoa,and also providing basic information for fauna or ecological studies,through detailed morphological and taxonomic description on frequent or new record species in this area.The main results are summarized as follows.1.30 ciliates belonging to 26 genera,24 families,15 orders,7 classes,were collected and identified using standard methods such as observing in vivo and protargol impregnation.In this paper,detailed description and rapid identification characteristics of 15 frequent species as well as the general morphology of the rest 15 species were given,which provides a reference for identification of ciliates in Chongming Island,Shanghai.2.One new genus,Arcanisutura n.gen.,was established,which could be easily distinguished from other related genera in having the inconspicuious and unique trendency anterior suture.Meanwhile,three new species,Arcanisutura chongmingiensis n.sp.,Apoholosticha parasinica n.sp.,and Lamtostyla chongmingiensis n.sp were described.A.chongmingiensis n.sp.is recognized mainly by its elongated body with a tail-like posterior end,fewer(25-33)somatic kineties and many(4-11)excretory pores;A.parasinica n.sp.differs from its congners mainly by having a longer body,fewer frontal cirri,fewer dosal kineties,three contractile vacuoles and colorless cortical granules scatting irregularly on ventral side;L.chongmingiensis n.sp.can be distinguished by fewer frotoventral cirri and many macronuclei.3.Taxonomic confusion or errors of three new Chinese record species were clarified for the first time.(1)Based on the morphological characters and statistical data,we denied Zosterodasys shumerica Aliev,1990 was the synonym of Z.transversa Foissner et al.1994.(2)Detailed observations of a neglected and insufficient described species,Marituja caudata Obolkina,1995,were conducted in vivo,on infraciliature and scanning electron microscopy,following with a new given defination.(3)The living characteristics of Euplotes platystoma Dragesco&Dragesco-Kerneis,1986 were supplemented.4.Six species,namely,Dysteria crassipes Claparede&Lachmann,1859,Zosterodasys shumerica Aliev,1990,Kentrophyllum qingdaoense Wu et al.,2015,Propostoma notate Mobius,1888,Blepharisma undulans Stein,1867 and Holosticha heterofoissneri Hu&Song,2001,were first reported and redescribed from the low-salinity tidal wetlands,revealing the high adaptability of these marine or freshwater species to low salinity.5.The temporal and spatial distribution patterns of ciliates in Chongming Island,Shanghai,were as follows:heterotrichs and hypotrichs were the dominant species in all sampling sites;the highest species diversity was observed in autumn;the order of the diversity of ciliate protozoa spatially was site 1>site 2>site 3 and site 4>site 5.This order among sites might be related to their salinity,vegetation and sediment types.