Additions and refinements to Sycodes glabra (Shumard, 1858), a poorly known Late Cretaceous (Campanian) marine gastropod from the northeast Pacific: taxonomic and biostratigraphic implications

L Squiresrichard,Grahamraymond

Canadian Journal of Earth Sciences(2014)

引用 1|浏览4
暂无评分
摘要
The Late Cretaceous marine gastropod Sycodes glabra (Shumard, 1858) from the northeast Pacific has been poorly known because the type, which was never figured, was lost in a fire in 1892, and the type locality was very poorly located. A neotype is selected from specimens collected by the early Canadians, geologist J. Richardson and eminent British Columbian naturalist Dr. C.F. Newcombe. Newly discovered material, as well as museum specimens, provide fundamental geologic and paleontologic information. The number of available specimens is 19, and nearly all are from submarine-fan deposits in the Upper Cretaceous Nanaimo Group exposed along the southeastern-coastal region of Vancouver Island, British Columbia, and on Big Sucia Island, northwestern Washington State, with nearly half of the specimens from the latter locale. A single specimen is from northern California. This present study better establishes the type locality for S. glabra and documents this name as the senior subjective synonym of ? Ficus cypraeoides Gabb, 1864. The geologic range of S. glabra is early Campanian (Submortoniceras chicoense ammonite Zone) to early late Campanian (Metaplacenticeras cf. pacificum ammonite Zone). Sycodes seems to be a monotypic genus, but Pyrula (Protopirula) capensis Rennie, 1930, from mid-Santonian to lower Campanian strata in South Africa, might be congeneric. Sycodes is questionably assigned herein to the family Ficidae Meek, 1864, and could be the earliest known ficid.
更多
查看译文
AI 理解论文
溯源树
样例
生成溯源树,研究论文发展脉络
Chat Paper
正在生成论文摘要