Study On The Biodiversity And Taxonomy Of Marine Nematodes At Mangroves In Fujian Province

In April, July, October,2012, and January, April,2013, meiofauna groups and abundance,nematode dominant genera and feeding types, community structure and pollution evaluation, aswell as classification were studied at five mangroves (Zhangjiangkou in Yunxiao county,Jiulongjiangkou in Longhai city, Fenglin in Xiamen, Luoyang River in Quanzhou, Wanwu inFu’an city) in Fujian province. The main results were as follows:(1)17groups of meiofauna in Fujian provincial mangrove were recorded, includingfree-living marine nematodes, copepods, polychaetes, oligochaetes, planarian, isopoda,amphipods, aquatic insects, tardigrata, chain insects, halacarid, cladocerans, bivalves,pycnogonum, decapod, esculenta and unidentified species. Among them, the free-living marinenematodes was absolutely dominant, the ratio was93.00%, followed by copepods, accountingfor4.58%, then oligochaeta (1.16%) and polychaetes (1.01%), others (planarian, isopoda,amphipods, aquatic insects, tardigrata, chain insects, halacarid, cladocerans, bivalves,pycnogonum, decapod, esculenta and unidentified species) shared less proportion of only0.25%.Seasonal variation of marine nematodes abundance in five pieces of mangroves was asfollows: Zhangjiangkou mangrove: spring> winter> autumn> summer; Longhai mangrove:winter> summer> spring> autumn; Fenglin mangrove: winter> summer> autumn> spring;Luoyang River mangrove: spring> winter> autumn (summer data missing); Wanwu mangrove:winter> autumn> summer (spring data missing). Statistical analysis by ANOSIM test, there weresignificant or very significant seasonal variation on nematode abundance at each sample area inmangroves. Higher numbers of nematodes were usually in winter and spring, the lower numberswere in summer and fall.(2) Individuals≥5%of nematodes genera at mangroves in Fujian province were followed,Sabatieria, Ptycholaimellus, Parasphaerolaimus, Terschellingia, Daptonema, Viscosia,Dichromadora, the ratio were19.82%,7.88%,7.45%,7.26%,6.79%,6.00%,5.25%,respectively.Seasonal changes on nematode feeding types at each mangrove area were as follows,Zhangjiangkou mangrove:1B>2A>2B>1A; Fugong mangrove:1B>2B>2A>1A; Fenglinmangrove:1B>2A>2B>1A; Luoyang River mangrove:2B>1B>2A>1A; Wanwu mangrove:2A>1B>2B>1A. As can be seen, nematodes(1B type) were dominant in Zhangzhou, Xiamen k.candel forest, nematodes(2A type) were dominant in Ningde k.candel forest, nematodes(2Btype) were dominant in Quanzhou aegiceras forests, all the nematodes(1A type) in five areas hadthe least numbers.(3) Nematode diversity index at mangroves in Fujian province showed that, H’ at LuoyangRiver mangrove was the highest,2.873, H’ at Wanwu mangroves was the lowest,2.647, analysisof variance didn’t show significant differences (p>0.05).Through the neutral model analysis and classification differences index calculation, theresults showed that five pieces of mangroves we studied were not affected by contamination.(4) In this paper,93genera,23family of marine nematodes were identified. We brieflydescribed seven individuals≥5%of nematodes genera (Sabatieria， Ptycholaimellus，Parasphaerolaimus，Terschellingia，Daptonema，Viscosia，Dichromadora). In addition, threenew species belong to Comesomatidae: Sabatieria coniseta sp.nov., Hopperia sinensis sp.nov.,Dorylaimopsis papilla sp.nov., were detailed description.