# Nevadella
> Mediated Wiki article. Canonical URL: https://mediated.wiki/source/Nevadella
> Markdown URL: https://mediated.wiki/source/Nevadella.md
> Source: https://en.wikipedia.org/wiki/Nevadella
> Source revision: 1355398144
> License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/)
{{Short description|Extinct genus of trilobites}}
{{Automatic taxobox
| fossil_range = Late [Atdabanian](/source/Atdabanian), {{Geological range|524|522}}
| image = Nevadella eucharis USNM PAL 60079.jpg
| image_caption = ''Nevadella eucharis'', type specimen
| taxon = Nevadella
| authority = Raw, 1936
| subdivision_ranks = Species
| subdivision =
* ''N. eucharis'' ([Walcott](/source/Charles_Doolittle_Walcott), 1913) ([type](/source/Type_(biology))) [synonym](/source/Synonym_(taxonomy)) ''Callavia eucharis''
* ''N. baculenta'' (Fritz, 1972)
* ''N. cartlandi'' (Raw in Walcott, 1910) synonyms ''Callavia cartlandi'', ''C. cobboldi'', ''C. brevioculata''[{{cite journal|last= Lieberman|first= B. S.|year= 2001|title= Phylogenetic Analysis of the Olenellina Walcott, 1890 (Trilobita, Cambrian)|journal= Journal of Paleontology|volume= 75|number= 1|pages= 96–115|url= http://www.bioone.org/doi/full/10.1666/0022-3360%282001%29075%3C0096%APAOTOW%3E2.0.CO%3B2|doi=10.1666/0022-3360(2001)075<0096:PAOTOW>2.0.CO;2|s2cid= 85656419|url-access= subscription}}]
* ''N. keelensis'' Abe, 2010
* ''N. mountjoyi'' (Fritz, 1972)
* ''N. perfecta'' (Walcott, 1913) synonym ''Callavia perfecta''
}}
left|thumb|Several cephalons of ''Nevadella perfecta'', with undamaged glabellas, also showing the strikingly wide cephalic margin'''''Nevadella''''' is an [extinct](/source/extinct) [genus](/source/genus) of [trilobites](/source/Trilobita), [fossil](/source/fossil) marine [arthropod](/source/arthropod)s, with species of average size (about {{convert|5|cm|in|disp=or}} long). It lived during the late [Atdabanian](/source/Atdabanian) stage, which lasted from 530 to 524 million years ago during the early part of the [Cambrian Period](/source/Cambrian_Period).[{{cite journal | last = Sepkoski| first = Jack| title = A compendium of fossil marine animal genera (Trilobita entry)| journal = Bulletins of American Paleontology| volume = 364| page = 560| year = 2002| url = http://strata.ummp.lsa.umich.edu/jack/showgenera.php?taxon=307&rank=class| access-date = 2008-01-12 }}]
== Etymology ==
The name is derived from ''[Nevadia](/source/Nevadia)'', a related genus.
== Taxonomy ==
''Nevadia'' predates ''Nevadella'' and may include its direct ancestor.
=== Species previously assigned to ''Nevadella'' ===
* ''N. burri'' = ''Pleisionevadella burri''
== Description ==
The body of ''Nevadella'' is very flat dorso-ventrally. The general outline of its thin, lightly calcified [exoskeleton](/source/exoskeleton) is inverted drop-shaped. The front is rounded, widest at the back of the headshield (or [cephalon](/source/Cephalon_(arthropod_head))), and tapering from there to an eventually rounded termination. The central area of the cephalon (or [glabella](/source/Cephalon_(arthropod_head))) is distinctly tapered forward, sides slightly concave, but wedging out slightly in the frontal half and with a rounded front (like the silhouette of a slim pawn). The glabella and the frontal margin almost or entirely touch (in jargon: the preglabellar field is short or absent). Cephalic margin at least as wide as the most frontal thoracal segment. The [thorax](/source/Trilobite) has 17 to 23 segments, gradually diminishing in size. The pleural spines are long and sickle-shaped. The tailshield (or [pygidium](/source/Trilobite)) is very small and subquadrate in shape.[{{cite book |author=H. B. Whittington|title=Treatise on Invertebrate Paleontology. Part O, Revised. Trilobita |chapter=Introduction, Order Agnostida, Order Redlichiida |year=1997|display-authors=etal}}]
== Distribution ==
Fossils of ''Nevadella'' have been found in the late Atdabanian of the USA (California, Nevada) and Canada (Cordilleran region).
* ''N. eucharis'' is known from the Middle Member of the Poleta Formation, Esmeralda County, Nevada, USA.[[http://paleodb.geology.wisc.edu/cgi-bin/bridge.pl?action=basicCollectionSearch&collection_no=10496 Paleobiology Database]{{Dead link|date=January 2026 |bot=InternetArchiveBot }}]
* ''N. keelensis'' is known from the Sekwi Formation, Northwest Territories, Canada.[F. R. Abe, B. S. Lieberman, M. C. Pope, K. Dilliard (2010). "New information on olenelline trilobites from the Cambrian Sekwi Formation in northwestern Canada". ''Canadian Journal of Earth Sciences'', 2010, '''47''' (12): 1445–1449.[http://www.nrcresearchpress.com/doi/abs/10.1139/E10-073]][{{Cite web |url=http://trilobites.lifedesks.org/node/690 |title=Life Desks, Trilobites on line |access-date=2012-03-04 |archive-date=2013-05-14 |archive-url=https://web.archive.org/web/20130514051603/http://trilobites.lifedesks.org/node/690 |url-status=dead }}]
* ''N. mountjoyi'' is known from the Mural Formation, north slope of Mount Mumm, Alberta, Canada.[{{Cite web |url=http://trilobites.lifedesks.org/node/696 |title=Life Desks, Trilobites on line |access-date=2012-03-04 |archive-date=2013-04-30 |archive-url=https://web.archive.org/web/20130430074918/http://trilobites.lifedesks.org/node/696 |url-status=dead }}]
* ''N. perfecta'' is known from the Mahto Formation, Mumm Peak on the west side of Hitka Pass, western Alberta, Canada.[U. S. National Museum, Catalogue No. 60082.]
== Ecology ==
Contemporary [taxa](/source/taxa) that also occur in the so-called "Nevadella" Zone include ''Esmeraldina'', ''Holmiella'', ''Palmettaspis'', ''[Bradyfallotaspis](/source/Bradyfallotaspis)'', ''[Geraldinella](/source/Geraldinella)'', ''[Paranevadella](/source/Paranevadella)'', ''[Nevadia](/source/Nevadia)'', ''[Buenellus](/source/Buenellus)'', and ''[Cirquella](/source/Cirquella)''.