| 词条 | Weymouthia (trilobite) |
| 释义 |
| fossil_range = {{Geological range|522|510|Lower Cambrian}} | image = Weymouthia_nobilis_linedrawing.jpg | image_upright = 0.4 | image_caption = Llinedrawing of Weymouthia nobilis | regnum = Animalia | phylum = Arthropoda | classis = Trilobita | ordo = Agnostida | familia = Weymouthiidae | genus = Weymouthia | genus_authority = Raymond, 1913 | type_species = Agnostus nobilis | type_species_authority = Ford, 1872 | subdivision_ranks = Species | subdivision =
}} Weymouthia is an extinct genus of eodiscinid agnostid trilobites, which lived at the end of the Lower Cambrian, in what are now the eastern United States, England, Siberia and China. DescriptionLike all Agnostida, Weymouthia is diminutive and the headshield (or cephalon) and tailshield (or pygidium) are of approximately the same size (or isopygous) and outline. Like all Weymouthiidae, Weymouthia lacks eyes and rupture lines (or sutures). The headshield (or cephalon) is approximately as long as wide, lacks facial sutures and is eyeless. The tailshield (or pygidium) is about 1.2× as wide as long. Both are effaced except for a furrow close to their borders. The cephalic border bears lateral tubercles. The thorax consists of three segments.[1] EtymologyWeymouthia is named after Weymouth, Massachusetts.[2]Distribution
References1. ^Whittington, H. B. et al. Part O, Treatise on Invertebrate Paleontology. Revised, Volume 1 – Trilobita – Introduction, Order Agnostida, Order Redlichiida. 1997 {{Taxonbar|from=Q7990395}}{{agnostida-stub}}2. ^{{cite web|url= http://www.weymouth.ma.us/index.php/history/historic-timeline/|accessdate= 3 December 2012|title= Weymouth, MA, history}} 3. ^{{cite journal|last= Hinz|first= I.|year= 1987|title= The Lower Cambrian microfauna of Comley and Rushton, Shropshire, England|journal= Palaeontographica Abteilung A|volume= 198|issue=1-3|pages= 41–100}} cited in {{cite web|title= Weymouthia nobilis|author= Paleobiology Database|url=http://paleodb.org/cgi-bin/bridge.pl?a=basicCollectionSearch&collection_no=79928}} 4 : Weymouthiidae|Agnostida genera|Cambrian trilobites|Cambrian trilobites of Europe |
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