水生生物学报2017，Vol.41Issue(4)：914-922,9.DOI:10.7541/2017.114
并基角毛藻若干分类学疑问的初步探讨
PRELIMINARY STUDY ON SOME TAXONOMIC PUZZLES OF CHAETOCEROS DECIPIENS CLEVE
摘要
Abstract
As one of the largest marine planktonic diatom genera,Chaetoceros Ehrenberg has a very wide biogeographi-cal distribution from polar to tropical waters.C. decipiens Cleve is a representative species of the genusChaetoceros characterized by the regular chains and stiff setae. The fusing part on the sibling setae bases was the unique characters forC. decipiens in the present taxonomy system that mainly built on morphology, which has been accepted and used by some diatom taxonomists. However, some other researchers hold different opinion, in which the fusing on the sibling setae bases was a variable morphological structure that could not give much significant taxonomic value. Meanwhile, some questions remain about the taxonomic position of the intraspecific units ofC. decipiens, which is difficult to an-swer whether these intraspecific units are independent taxonomic units or just a living stage of life cycle ofC. decipi-ens. To answer this question, the monoclonal stains and the combination of morphology features and molecular analy-sis will be required. To do this, several monoclonal strains were established from several Chinese representative sites using glass micropipette under invert microscopy according with the present taxonomic morphology ofC. decipiens. The morphology was studied by light microscopy, scanning electron microscopy and transmission electron microscopy. Meanwhile, the hypervariable region (D1-D3) of nucleic large subunit ribosomal rRNA encoding gene was amplified and sequenced as molecular evidence. The result indicated that the fusing of sibling setae base was not a steady struc-ture, which could not be considered as significant morphological feature for the accurate identification ofC. decipiens, and that some similar species without fusing of sibling setae base could be the trueC. decipiens. Moreover, according to the molecular phylogenetic analysis, high diversity was hidden in the morphologically-identifiedC. decipiens andC. lorenzianus, which might show the presence of cryptic and pseudo-cryptic species. Inaddition,C. decipiens f.singula-ris Gran was confirmed as a temporary stage of whole life cycle ofC. decipiens based on the continuous observation during cultures maintainance. Finally, they totally shared the same LSU sequences. Thus,C. decipiens f.singularis Gran was proposed as the synonym ofC. decipiens.关键词
并基角毛藻/分类学/角毛基部并行融合/并基角毛藻单胞变型Key words
Chaetoceros decipiens/Taxonomy/Fusing of sibling setae base/C. decipiens f.singularis分类
农业科技引用本文复制引用
陈作艺,李扬..并基角毛藻若干分类学疑问的初步探讨[J].水生生物学报,2017,41(4):914-922,9.基金项目
国家自然科学基金(31570205和31370235) （31570205和31370235）
广东省科技计划项目(2015A030401084)资助[Supported by the National Natural Science Foundation of China (31570205,31370235) （2015A030401084）
Guangdong Province Science and Technology Program (2015A030401084)] （2015A030401084）
