Buenellus higginsiis an average size (about 5 centimetres or 2.0 inches)trilobite,which lived during theLowerCambrianperiod, in what is now North-WestGreenland.It is a prominent member of theSirius Passetfauna.Buenellus higginsiis the only known species in the genusBuenellus(i.e., the genus ismonotypic).
| Buenellus higginsi Temporal range:
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| Buenellus higginsifossils at the Geological Museum, Copenhagen | |
Scientific classification
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| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Class: | †Trilobita |
| Order: | †Redlichiida |
| Family: | †Nevadiidae |
| Genus: | †Buenellus Blaker, 1988 |
| Species: | †B. higginsi
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| Binomial name | |
| †Buenellus higginsi Blaker, 1988
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Etymology
editThe genus name is a contraction of Buen, from the formation in which it was first collected, andOlenellus,a somewhat related trilobite genus. The speciesspecific epithethonors A. Higgins, who discovered the Sirius PassetLagerstättein 1984 during the Geological Survey of Greenland.
Description
editThe 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 (orcephalonis approximately5⁄8× as long as it is wide. The (in this case only slightly) vaulted central axis of the head orglabellatapers gently forward and does not reach the anterior margin. The outer backside of the cephalon (or genal angle) has short genal spines. Thethoraxhas 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 smallpygidium.Pleural spines are short, and the pleural regions are only slightly wider than the axis.[1][2]
Differences with other Nevadiidae
editThe general shape of the body of other species in the Nevadid family (likeNevadiaandNevadella) is shorter, with the greatest width across the back of the cephalon, and the entire thorax tapering backwards.
Distribution
editBuenellus higginsihas been collected from early to middleAtdabaniandeposits at the lowerBuen Formation( “Nevadella” Zone),Sirius Passetlagerstätteat its junction with the J. P. Koch Fjord, Peary Land, Greenland82°47.6′N42°13.7′W/ 82.7933°N 42.2283°W.It has also been reported fromNovaya Zemlya,Russian Republic.
Ecology
editMineral-filled gut tracts inB. higginsisuggest they were not filled with sediment at the time of burial, and that the species was apredatorof soft prey.
Healed injuries, some of which are the result of unsuccessful predaceous attacks, are not uncommon inB. higginsi.Carnivory onB. higginsiis also implied by the remains ofanomalocarididsand other potential predators.[3]
Other exoskeletons show evidence of post-mortem disruption, perhaps because of scavenging.Buenellus higginsi,one of the earliest known trilobites fromLaurentia,seems to have played an important role in the Sirius Passet ecosystem, serving both as predator on, and prey for, contemporary animals.[4]
Habitat
editBuenellus higginsiwas 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.[5]
Soft tissue preservation
editMany specimens ofB. higginsishow 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.[4]
References
edit- ^Mark R. Blaker & John S. Peel (1997).Lower Cambrian trilobites from North Greenland.Meddelelser om Grønland. Geoscience. Vol. 35.ISBN978-87-635-1241-1.
- ^H. B. Whittington; et al. (1997). "Introduction, Order Agnostida, Order Redlichiida".Treatise on Invertebrate Paleontology. Part O, Revised. Trilobita.
- ^Loren E. Babcock(2002).Anatomy, paleoecology, and taphonomy of the trilobiteBuenellusfrom the Sirius Passet biota (Cambrian), North Greenland.Geological Society of America Annual Meeting. Denver, Colorado. paper no. 75-8.
- ^abLoren E. Babcock & John S. Peel (2003)."Palaeobiology, taphonomy and stratigraphic significance of the trilobiteBuenellusfrom the Sirius Passet biota, Cambrian of North Greenland ".Memoirs of the Association of Australasian Palaeontologists.34:401–418.
- ^John S. Peel & Martin Stein (2009)."A new arthropod from the Lower Cambrian Sirius Passet fossil-Lagerstätten of North Greenland"(PDF).Bulletin of Geosciences.84(4): 625–630.doi:10.3140/bull.geosci.1158.
External links
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Data related toBuenellusat Wikispecies
