View source for Biology:Buenellus

{{Short description|Species of trilobite (fossil)}}
{{Italic title}}
{{Taxobox
| name= ''Buenellus higginsi''
| fossil_range = {{fossilrange|526|521|Atdabanian}}
| image = Buenellus.jpg
| image_caption = ''Buenellus higginsi'' fossils at the Geological Museum, Copenhagen
| regnum = [[Biology:Animal|Animal]]ia
| phylum = [[Biology:Arthropod|Arthropod]]a
| classis = [[Biology:Trilobite|Trilobita]]
| ordo = [[Biology:Redlichiida|Redlichiida]]
| subordo = [[Biology:Olenellina|Olenellina]]
| superfamilia = "Nevadioidea"<ref name='Lieberman 1998'>{{cite journal|last1=Lieberman |first1=B.S. |year=1998 |title=Cladistic Analysis of the Early Cambrian Olenelloid Trilobites |journal=Journal of Paleontology |volume=72, part 1 |pages=59–78 |doi=10.1017/S0022336000024021 |bibcode=1998JPal...72...59L |s2cid=86307339 |url=http://invitestock.free.fr/Cambrien/pdf/Spanish%20fauna/Cladistic%20Analysis%20of%20the%20Early%20Cambrian%20Olenelloid%20Trilobites.pdf }}{{dead link|date=November 2016 |bot=InternetArchiveBot |fix-attempted=yes }}</ref>
| familia = "Nevadiidae"
| genus= '''''Buenellus'''''
| genus_authority = Blaker, 1988
| species = '''''B. higginsi'''''
| binomial = ''Buenellus higginsi''
| binomial_authority = Blaker, 1988
}}
'''''Buenellus higginsi''''' is an average size (about {{convert|5|cm|in|disp=or}}) [[Biology:Trilobite|trilobite]], which lived during the Lower [[Earth:Cambrian|Cambrian]] period, in what is now North-West [[Place:Greenland|Greenland]]. It is a prominent member of the Sirius Passet fauna. ''Buenellus higginsi'' is the only known species in the genus '''''Buenellus''''' (i.e., the genus is [[Biology:Monotypic taxon|monotypic]]).

== Etymology ==
The genus name is a contraction of Buen, from the formation in which it was first collected, and ''[[Biology:Olenellus|Olenellus]]'', a somewhat related trilobite genus. The species [[Biology:Specific name (zoology)|specific epithet]] honors A. Higgins, who discovered the Sirius Passet ''{{lang|de|Lagerstätte}}'' in 1984 during the Geological Survey of Greenland.

== Description ==
The general outline of the body is rounded n the front third, parallel sided in the middle third, and progressively tapering backwards in the back third, ending at an angle of approximately 45° with the midline. The headshield (or [[Biology:Cephalon (arthropod head)#Trilobites|cephalon]] is approximately ⅝× as long as it is wide. The (in this case only slightly) vaulted central axis of the head or [[Biology:Cephalon (arthropod head)|glabella]] tapers gently forward and does not reach the anterior margin. The outer backside of the cephalon (or genal angle) has short genal spines. The [[Biology:Trilobite#Thorax|thorax]] has 17 or 18 articulating segments, maintaining width or widening slightly backwards up to the 8th segment, then tapering posteriorly. The posterior segment may be fused with the anterior part of a simple and small [[Biology:Trilobite#Pygidium|pygidium]]. Pleural spines are short, and the pleural regions are only slightly wider than the axis.<ref>{{cite book |author=Mark R. Blaker & John S. Peel |year=1997 |title=Lower Cambrian trilobites from North Greenland |series=Meddelelser om Grønland. Geoscience |volume=35 |url=https://books.google.com/books?id=wxNL2nasZ2IC&pg=PA50 |isbn=978-87-635-1241-1}}</ref><ref>{{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=0}}</ref>

=== Differences with other Nevadiidae ===
The general shape of the body of other species in the Nevadid family (like ''[[Biology:Nevadia|Nevadia]]'' and ''[[Biology:Nevadella|Nevadella]]'') is shorter, with the greatest width across the back of the cephalon, and the entire thorax tapering backwards.

== Distribution ==
''Buenellus higginsi'' has been collected from early to middle Atdabanian deposits at the lower [[Earth:Buen Formation|Buen Formation]] (“Nevadella” Zone),  Sirius Passet lagerstätte at its junction with the J. P. Koch Fjord, Peary Land, Greenland {{Coord|82|47.6|N|42|13.7|W}}. It has also been reported from Novaya Zemlya, Russian Republic.

== Ecology ==
Mineral-filled gut tracts in ''B. higginsi'' suggest they were not filled with sediment at the time of burial, and that the species was a predator of soft prey.

Healed injuries, some of which are the result of unsuccessful predaceous attacks, are not uncommon in ''B. higginsi''. Carnivory on ''B. higginsi'' is also implied by the remains of [[Biology:Anomalocaridid|anomalocaridid]]s and other potential predators.<ref>{{cite conference |author=Loren E. Babcock |year=2002 |title=Anatomy, paleoecology, and taphonomy of the trilobite ''Buenellus'' from the Sirius Passet biota (Cambrian), North Greenland |conference=Geological Society of America Annual Meeting |id=paper no. 75-8 |url=http://gsa.confex.com/gsa/2002AM/finalprogram/abstract_40288.htm |location=Denver, Colorado}}</ref>

Other exoskeletons show evidence of post-mortem disruption, perhaps because of scavenging. ''Buenellus higginsi'', one of the earliest known trilobites from [[Earth:Laurentia|Laurentia]], seems to have played an important role in the Sirius Passet ecosystem, serving both as predator on, and prey for, contemporary animals.<ref name='Babcock and Peel'/>

== Habitat ==
''Buenellus higginsi'' was probably a marine bottom dweller, that lived in deeper water. This may be deduced from the dominance of eyeless forms and the absence of seaweeds at the collection site.<ref>{{cite journal |author=John S. Peel & Martin Stein |year=2009 |title=A new arthropod from the Lower Cambrian Sirius Passet fossil-Lagerstätten of North Greenland |journal=Bulletin of Geosciences |volume=84 |issue=4 |pages=625–630 |url=http://www.geology.cz/bulletin/contents/2009/vol84no4/1158_peel.pdf |doi=10.3140/bull.geosci.1158|doi-access=free }}</ref>

== Soft tissue preservation ==
Many specimens of ''B. higginsi'' show some form of exceptionally preserved, non-biomineralised tissue. Structures interpreted as alimentary tracts and probable digestive glands are commonly preserved. The slender antennas are rarely preserved.<ref name='Babcock and Peel'>{{cite journal |author=Loren E. Babcock & John S. Peel |year=2003 |title=Palaeobiology, taphonomy and stratigraphic significance of the trilobite ''Buenellus'' from the Sirius Passet biota, Cambrian of North Greenland |journal=Memoirs of the Association of Australasian Palaeontologists |volume=34 |pages=401–418 |url=http://search.informit.com.au/documentSummary;dn=219894361622173;res=IELHSS}}</ref>

== References ==
{{Reflist|32em}}

== External links ==

{{Taxonbar|from1=Q4985496|from2=Q18607686}}

[[Category:Olenellina]]
[[Category:Prehistoric arthropod genera]]
[[Category:Cambrian trilobites]]
[[Category:Buen Formation| ]]

{{Sourceattribution|Buenellus}}