As one of the important microzooplankton in marine pelagic habitats,tintinnids are classified as neritic genera,oceanic genera and cosmopolitan genera.Until now,we know little about the interaction between neritic and oceanic genera in continental shelves.Low species richness area was found in the mixing area between neritic and oceanic genera in the East China Sea.In this study,we investigated the spatial distribution of tintinnid community throughout the entire Bohai Sea in May(spring)of 2014 to find out:(1)whether the tintinnid assembalges differed in the three major bays bordering this shallow inland sea;(2)whether there was low species richness area in the Bohai Sea.Three genera and 11 species attributed to neritic and cosmopolitan taxa were reported from this region.Tintinnid abundance averaged(81±216)ind./L(0–1234 ind./L).Tintinnid community differed within the three major bays,with each characterized by different tintinnid taxa.Referring to the average abundance of three bays,tintinnids were most abundant in the Laizhou Bay((328±445)ind./L),and least abundant in the Liaodong Bay((34±57)ind./L).A low species richness area occurred in the central Bohai Sea(20–40 m isobaths),in some stations of which no tintinnid was recorded.Our study demonstrates that tintinnid community varied greatly over small spatial scales,and low species richness area was found in the mixing area between neritic and oceanic genera within this inland sea.
Tintinnid ciliates are important pelagic microplankton.Most studies previously conducted in the Amundsen Sea have covered a relatively small latitude range and provided minimal information about tintinnid species composition and distribution.The present study was conducted to investigate tintinnid assemblages from the Antarctic zone(AZ)northward through the polar front(PF)to the subantarctic zone(SAZ).A total of 17 tintinnid species belonging to seven genera were collected,and 16 were identified.Results show that nine of the species are endemic to the Southern Ocean and they mainly inhabit the AZ near Antarctic continent with an abundant proportion exceeding 60%of total tintinnid.According to the tintinnid abundance distribution,the species were divided into four groups:Group I includes Acanthostomella norvegica,Codonellopsis glacialis,C.pusilla and Cymatocylis antarctica and mainly occurs in the northern boundary of the PF;Group II includes Cymatocylis convallaria forma calyciformis,an unidentified species,and Amphorellopsis quinquealata and mainly inhabits the PF;Group III includes Salpingella costata,Cymatocylis vanhoeffeni,C.convallaria forma cristallina,C.convallaria forma drygalskii,C.convallaria,Codonellopsis gaussi,and Laackmanniella naviculaefera and mainly occurs in the AZ near the Antarctic continent;and Group IV,which comprises Salpingella sp.and inhabits all zones.The new species of tintinnid(belonging to Group II)primarily inhabit the AZ but also are distributed in the PF,and they have large lorica-oral-diameter(LOD).The distribution ranges of tintinnid assemblages from the AZ to PF were determined,in addition to the different assemblages mixed in the PF.The information provided in this study increases our understanding of tintinnid assemblages from the Antarctic continent in the Antarctic Circumpolar Current and Antarctic waters.
In order to investigate the tintinnid diversity, vertical distribution and latitudinal variation in the tropical West Pacific Ocean, water samples of different depths from surface to 200 m were collected along four transects. Totally 124 tintinnid species in 39 genera were detected. Most species preferred to live in the surface and subsurface waters. High tintinnid species richness, abundance and diversity index mainly occurred at depths slight shallower than the layer of deep chlorophyll maximum. Species richness, abundance and Shannon＇s diversity index were significant positive correlation with temperature and chlorophyll a in vivo fluorescence, but significant negative correlation with salinity and depth. The correlations between most dominant species and environmental factors were not significant. Tintinnid diversity was extremely high in this area, species richness ranged from 25 to 52 at each station, Shannon＇s diversity indexes were higher than 3 at most sampling positions from surface to 75 m. Proportions of redundant species were high, accounted for 87.90% of species pool and 60.38% of total abundance, indicating high capacity to response to changes in resource composition and predation pressures of tintinnid communities in the tropical West Pacific Ocean.
LI HaiboZHANG WuchangZHAO YuanZHAO LiDONG YiWANG ChaofengLIANG ChenXIAO Tian
A new tintinnid ciliate, Tintinnopis estuariensis Zhang, Feng ＆ Yu, sp. nov. was found in the estuary of Yangtze River, China. It was most abundant in September. Its arenaceous lorica is cylindro-conical in shape, （120-180）μm x （50-75）pm in size, agglutinated with mineral particles, and open at both ends. Two characters distinguish it from others： the unique lateral flattened posterior portion with a vertical aboral opening and wider oral diameter. It occurred in water with surface temperature of 14-27℃ and surface salinity of 3.9‰-29.8‰.
于2012年11月18日至12月21日,在黄、东海沿从南向北（26~36°N）一个断面24个站采样调查了表层（4 m）砂壳纤毛虫群落。共发现砂壳纤毛虫17属,32种。各站砂壳纤毛虫种丰富度为2~15种,砂壳纤毛虫总丰度为2478~88550个/m3。整个断面优势种为筒状拟铃虫、白领细壳虫、小领细壳虫和钝囊坎虫。巴西拟铃虫仅出现在青岛近岸（24号站）,但丰度很高（10960个/m3）。砂壳纤毛虫种类多样性从南向北降低,从近岸向远岸增加,黏着壳的比例在近岸水浅处较多,在水深大于50 m 的站位,透明壳所占比例大大增加。不同种类的砂壳纤毛虫有着不同的分布区域,根据分布区域的不同,可分为南方种,北方种和广布种等。聚类分析结果显示,调查区的砂壳纤毛虫可以分为3个群落。
