# Emucaris

> Mediated Wiki article. Canonical URL: https://mediated.wiki/source/Emucaris
> Markdown URL: https://mediated.wiki/source/Emucaris.md
> Source: https://en.wikipedia.org/wiki/Emucaris
> Source revision: 1333079871
> License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/)

{{Short description|Extinct genus of arthropods}}
{{Speciesbox
| name= ''Emucaris fava''
| image = Emucaris fava.jpg
| image_caption = ''Emucaris fava''
| fossil_range = {{fossil range|Cambrian Stage 4}}
| parent_authority = Paterson ''et al.'', 2010
| authority = Paterson ''et al.'', 2010
| genus = Emucaris
| species = fava
}}

'''''Emucaris fava''''' is an [extinct](/source/extinct) [species](/source/species) of soft-shelled [trilobite](/source/trilobite)-like [arthropod](/source/arthropod) of the [nektaspid](/source/Nektaspida) [order](/source/Order_(biology)) from the [Lower Cambrian](/source/Lower_Cambrian) (Cambrian Stage 4) of [South Australia](/source/South_Australia). It is the only species classified under the [genus](/source/genus) '''''Emucaris'''''.<ref name="paterson2010"/>

== Etymology ==
The generic name is derived from the Emu Bay Shale, the deposit where the species was collected, and the [Latin](/source/Latin) word ''{{lang|la|caris}}'' meaning shrimp. The specific name ''fava'' is from the Latin word for [honeycomb](/source/honeycomb), for the ornamentation on its pygidial axis.<ref name="paterson2010">{{cite journal|author1=John R. Paterson |author2=Gregory D. Edgecombe |author3=Diego C. García-Bellido |author4=James B. Jago |author5=James G. Gehling |year=2010|title=Nektaspid arthropods from the Lower Cambrian Emu Bay Shale ''Lagerstätte'', South Australia, with a reassessment of lamellipedian relationships|journal=Palaeontology|volume=53|issue=Part 2|pages=377&ndash;402|url=http://www.nhm.ac.uk/resources-rx/files/paterson-et-al-2010-emucaridids-94061.pdf|doi=10.1111/j.1475-4983.2010.00932.x|bibcode=2010Palgy..53..377P |doi-access=free}}</ref>

== Description ==
The outline of the [dorsal](/source/Dorsal_(anatomy)) [exoskeleton](/source/exoskeleton) of ''E. fava'' is pointed inverted egg-shaped, between {{convert|1.5|cm|in}} and {{convert|3|cm|in}} long and about {{frac|1|2|3}} times as long as wide. The axis is up to 15% of the width of the body and only slightly raised. The semi-circular headshield (or [cephalon](/source/Cephalon_(arthropod_head))) is about half as long as the tailshield ([pygidium](/source/Trilobite)), and in between them four short [thoracic](/source/thorax) body segments ([somite](/source/somite)s). When disregarding the border, the pygidium of ''Emucaris'' is a triangle with a rounded termination, carrying a spine that ends at the outer rim of the border. There is no discernible segmentation visible. The axis in ''Emucaris'' is about one fifth of the pygidium and has a pattern of polygons of approximately equal area. The border of the cephalon is inconspicuous, and the border of the pygidium is longer than the somites. This border lacks ornamentation.<ref name="paterson2010"/>

=== Differences from ''Kangacaris'' === 
''[Kangacaris](/source/Kangacaris)'' has only three thorax segments. The exoskeletal outline of ''Kangacaris'' is an inverted egg-shape. The axis of the pygidium of ''Kangacaris'' is a third of the width of the body and clearly segmented. The axis of the pygidium ''Kangacaris'' lacks a terminal spine. The pygidial border of ''Kangacaris'' has 17 equally spaced ridges perpendicular to the edge of the border.

== Distribution ==
Fossils of ''E. fava'' were collected from the [Emu Bay Shale](/source/Emu_Bay_Shale) of [Kangaroo Island](/source/Kangaroo_Island), South Australia.

==References==
{{Reflist}}

{{Artiopoda}}
{{Taxonbar|from=Q5374863}}

Category:Nektaspida
Category:Monotypic artiopod genera
Category:Prehistoric arthropods of Australia
Category:Emu Bay Shale

---
Adapted from the Wikipedia article [Emucaris](https://en.wikipedia.org/wiki/Emucaris) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Emucaris?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.