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黔东寒武纪地层出露完整、连续,有利于进行地层研究。剑河交榜剖面杷榔组、松山剖面“清虚洞组”及乌溜-曾家崖剖面凯里组下部产大量广布性掘头虫类三叶虫及浅水相区分子莱得利基虫类三叶虫,为寒武系第二统第四阶生物地层的划分提供了丰富材料。其中交榜剖面杷榔组三叶虫共8属10种:Arthricocephalus chauveaui、Arthricocephalus xinzhaiheensis、Balangia balangensis、Changaspis elongata、Duyunaspis duyunensis、Oryctocarella duyunensis、Oryctocarella balangensis、Probowmania balangensis、Redlichia(Pteroredlichia)chinensis、Longaspis paiwuensis。松山剖面“清虚洞组”三叶虫共15属19种:Arthricocephalus chauveaui、Burlingia balangensis、Balangcunaspis transversus、Dinesus panxinensis、Duyunaspis jianheensis、Danzhaina lilia、Eoptychoparia cf.yunnanensis、Eoptychoparia gaodongensis、Mufushania cf.nankingensis、Nangaops danzhaiensis、Olenoides constrictus、Olenoides cf.hubenensis、Oryctocarella duyunensis、Protoryctocephalus arcticus、Panxinella angustilimbata、Redlichia(Redlichia)guizhouensis、Redlichia(Redlichia)nobilis、Redlichia(Pteroredlichia)chinensis、Yuehsienszella magna。乌溜-曾家崖剖面凯里组下部三叶虫丰富,共计27属27种:Bathynotus kueichouensis、Balangcunaspis transversus、Burlingia ovata、Chittidilla brevis、Danzhaina conica、Eodouposiella taijiangensis、Eokaotaia gedongensis、Euarthricocephalus taijiangensis、Kermanella angustilimabata、Kunmingaspis yunnanensis、Mufushania nankingensis、Nangops brevis、Nangoia megaceps、Oryctocephalops guizhouensis、Ovatoryctocara sinensis、Olenoides hubeiensis、Oryctocephalites longus、Protoryctocephalus balangensis、Probowmania balangensis、Parashuiyuella subcylindrica、Pagetia significans、Qiannanagraulos costatus、Redlichia(Redlichia)takooensis longispina、Sinoschistometopuus latilimbata、Schmalensia rara、Sanwania prima、Xingrenaspis xingrenensis。以采集的三叶虫的地层延限及地理分布为依据,将剑河寒武系第二统第四阶三叶虫生物地层划分为(自下而上):Oryctocarella duyunensis-Arthricocephalus chauveaui间隔带;Arthricocephalus chauveaui延限带;Protoryctocephalus arcticus延限带;Bathynotus kueichouensis-Ovatoryctocare sinensis组合带。其中Oryctocarella duyunensis-Arthricocephalus chauveaui带与滇东Palaeolenus带及华北Palaeolenus带的顶界大致相当;Arthricocephalus chauveaui带的底界要低于滇东Hoffetella-Redlichia(Pteroredlichia)chinensis带的底界,高于华北Redlichia(Pteroredlichia)chinensis带的底界,且Arthricocephalus chauveaui带的顶界要低于华北Redlichia(Pteroredlichia)chinensis带的顶界;Protoryctocephalus arcticus延限带的顶、底界要底、高于滇东Redlichia(Redlichia)guizhouensis带,华北Redlichia(Redlichia)nobilis带的顶、底界要底、高于黔东剑河Protoryctocephalus arcticus带的顶、底界。