A New Type Eocrinoids of Echinoderms from the Balang Formation in Cambrian at Xiasi Town, Majiang County, Guizhou Province,China
-
摘要: 和凯里生物群一样,贵州寒武系杷榔动物群也含有丰富的棘皮动物始海百合化石,包括两个属种即俞氏贵州始海百合 GuizhoueocrinusyuiZhao,ParsleyetPeng,2007及殷氏原始球状始海百合(新属新种)Protogloboeocrinusyini(gen.etsp. nov.).其中新属种是近期在杷榔组分布区南部贵州麻江下司淑里村杷榔组上部发现的,是凯里组中球形球状始海百合(GloboeocrinusglobolusZhao, ParsleyetPeng,2008)的原始属种,两者均具有发育的吸盘、长的茎、近于球形或椭球形的萼及较长 的腕.但新属种茎呈倒长锥柱形,缝孔长卵形,腕枝数少,两者区别明显.Protogloboeocrinusyini(gen.etsp.nov.)的发现及研 究,不仅追溯到凯里组球形球状始海百合的原始属种,了解两者演化规律是茎变短,萼变球形,缝孔变为圆形,腕枝数量增加, 捕食能力增强.而且还增添了杷榔组始海百合的多样性及其分区性:杷榔组分布区北部仅见Guizhouocrinusyui,南部仅见 Protogloboeocrinusyini(gen.etsp.nov.)Abstract: Like Kaili Biota, Balang Fauna in Cambrian also contains abundant eocrinoids fossils including two genera and spe- cies, which are(Julzhoueocrlnus yui Zhao, Parsley et Peng, 2007 and Protogioioeocrlnus yln1(gen. et sp. nov.). New genus and species described occur in the upper part of Balang Formation at Shuli Vi11age, Xiasi Town, Majiang County, Guizhou Province, which is1ocated in the southern part of the Balang Formation distribution area. Protogiof7oeocrlnus ylm (gen. et sp. nov.) is a primitive genus and species of (_;iof7oeocllnus gioioius Zhao, Parsley et Peng, 2008 from the Kaili Formation. Both have deve1oped osculum, nearly spherica1 or spheroida1 theca, 1ong brachioles, but new genus and species differ from thelatter in having1ong inverted conica1 column stalk, nearly spherica1 or e11ipsoida1 theca, 1ong ova1 sutura1 pore andless bronchioles. The discoveryand studyof Protogiof)oeocrinus ylm (gen. et sp. nov.) reviews primitive genus and species of Gio,l)oeocllnus gio6oius and provides evidences for evolutiona1 trend between the two in genera and species such as stalk shortening, 1ong in- verted conica1 column changing to short inverted conica1 column, theca changing g1oba1 in shape, sutura1 pore changing from 1ong ova1 form to round form, more brachioles in number. In addition, the bio1ogica1 diversity of eocrinoids from Balang For- mation is enriched and bio1ogica1 partition of eocrinoids from Balang Formation is enhanced. The G·lizhoueocrlnus yui only oc- cur in the northern part of the distribution area of Balang Formation and ProtogiofJoeocllnus yim (gen. et sp. nov.) only occur in the southern part of the distribution area of Balang Formation.
点击查看大图
计量
- 文章访问数: 2998
- HTML全文浏览量: 69
- PDF下载量: 309
- 被引次数: 0