摘要
近期在西乡化石库中发现了原始锥石类Carinachites tetrasulcatus新材料。与以往C.tetrasulcatus所不同的是,其角沟窄且浅,不但有呈现出张开状态的角沟,还发现有呈现出闭合状态的角沟化石材料。锥面具有清晰的横肋,角沟处未见横纹。最重要的是发现固着端组织结构的保存,据此推断原始锥石类可能为营固着生活的水螅型刺胞动物。其角沟的闭合、微张以便于扩大、缩小口端与中央腔,扰动海水,加快水流,加速滤食。处于梅树村阶第Ⅱ化石组合带的C.tetrasulcatus与处于第Ⅲ化石组合带的六方锥石科中的Septuconularia yanjiaheensis具有一致的闭合角沟和锥面横肋形态等特征,推断C.tetrasulcatus可能为骨状锥石类向六方锥石类演化的过渡类型。
New specimens of Carinachites tetrasulcatus were discovered in the Xixiang Lagerstätte.Their narrow and shallow corner grooves are obviously different fromC.tetrasulcatus previously reported.The corner grooves of C.tetrasulcatus are closed or slightly open.Transverse ribs on the faces are distinct,no transverse striation is found in corner grooves.Fortunately,one fossil preserved a rare apex.It is inferred that the Protoconulariids may be hydratype Cnidaria.The closure and opening of the corner groove is convenient to expand and narrow the oral end and central cavity for stirring the seawater,speeding up water flow and filter-feeding.The morphology and structure of C.tetrasulcatus from the SSFs Assemblage ZoneⅡin Meishucunian Stage are similar to Septuconulariafrom the SSFs Assemblage ZoneⅢ(eg.the closed corner grooves and transverse ribs).Therefore,C.tetrasulcatus most likely represent an evolutionary intermediate form between Carinachitidae and Hexangulaconularidae.
作者
李林璐
刘云焕
邵铁全
张亚楠
秦嘉琛
王琪
周星宇
刘明金
LI Linlu;LIU Yunhuan;SHAO Tiequan;ZHANG Yanan;QIN Jiachen;WANG Qi;ZHOU Xingyu;LIU Mingjin(School of Earth Science and Resources,Chang’an University,Xi’an 710054;Shaanxi Key Laboratory of Early Life and Environment(Northwest University),Xi’an 710069)
出处
《微体古生物学报》
CSCD
北大核心
2021年第2期131-139,共9页
Acta Micropalaeontologica Sinica
基金
国家自然科学基金(Nos.41872014,41572007,41572009)
中国科学院战略性先导科技专项(No.XDB26000000)
中国科学院南京地质古生物研究所现代古生物学和地层学国家重点实验室(No.193123)
陕西省自然科学基础研究计划(No.2018JM4002)
长安大学大创项目(No.202010710458)
长安大学第十二届“挑战杯”竞赛(No.D-P-B-1)联合资助。
