Evolutionary significance of pylentonemid radiolarians and their late   Devonian species from southwestern Tianshan, China

CORC > 北京大学 > 地球与空间科学学院

	Evolutionary significance of pylentonemid radiolarians and their late Devonian species from southwestern Tianshan, China
	Liu Yu ; Hao Shougang
刊名	acta geologica sinica english edition
	2006
关键词	radiolarian spumellarian nassellarian entactinids pylentonemids phylogenetic evolution Late Devonian southwestern Tianshan
英文摘要	A group of radiolarian fossils with a complete morphological gradient of increasing polarization are reported from upper Devonian successions in southwestern Tianshan, China. Specifically, the important transitional mophotypes, Pylentonema transitorum sp. nov., Archocyrtium medium sp. nov. and Quadrapesus transitivus sp. nov., were found. Based on the fact that the new transitional radiolarian fossils resemble more closely to pylentonemids (cyrtoid nassellarians) than to entactinids (spumellarians) in morphology, they are assigned to pylentonemids. Pylentonemids share characters of both the Nassellaria (e.g., horned cephalis, basal opening with pylome) and Spumellaria (e.g., system of trabecular spicules), and they are thus of evolutionary significance. The evolutionary trend from spumellarians to nassellarians is characterized by (1) internal spicule: from simple trabecular spicules to complicate components (A;Ir,II;D;V;Lr,Li;MB); (2) polarization of the radiolarian tests due to rearrangment of spine, from radial to an axial symmetry; (3) the gradual formation of a basal opening (aperture, pylome, or podome); and the transition from a pseudopylome, a primative pylome with a narrow margin on the outer shell, to a true pylome rimmed with a narrow, elevated impermite wall.; http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000243019200005&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701 ; Geosciences, Multidisciplinary; SCI(E); 10; ARTICLE; 5; 647-655; 80
语种	英语
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/156027]
专题	地球与空间科学学院
推荐引用方式 GB/T 7714	Liu Yu,Hao Shougang. Evolutionary significance of pylentonemid radiolarians and their late Devonian species from southwestern Tianshan, China[J]. acta geologica sinica english edition,2006.
APA	Liu Yu,&Hao Shougang.(2006).Evolutionary significance of pylentonemid radiolarians and their late Devonian species from southwestern Tianshan, China.acta geologica sinica english edition.
MLA	Liu Yu,et al."Evolutionary significance of pylentonemid radiolarians and their late Devonian species from southwestern Tianshan, China".acta geologica sinica english edition (2006).