Emuella

{{Automatic taxobox

| fossil_range = {{Geological range|517}} late Botomian

| image = EmuellaPolymera.jpg

| image_caption = Emuella polymera of the Emuella genus; Lower Cambrian Emu Shale, Kangaroo Island, South Australia
(courtesy of Dave Simpson)

| taxon = Emuella

| authority = Pocock, 1970

| subdivision_ranks = Species

| subdivision =

Emuella polymera Pocock, 1970{{cite journal|last1= Paterson|first1= J.R.|last2= Edgecombe|first2= G.D.|title= The Early Cambrian Trilobite Family Emuellidae Pocock, 1970: Systematic Position and Revision of Australian Species|year= 2006|journal= Journal of Paleontology |volume= 80|issue= 3|pages= 496–513|url= http://www.bioone.org/doi/full/10.1666/0022-3360%282006%2980%5B496%3ATECTFE%5D2.0.CO%3B2|doi=10.1666/0022-3360(2006)80[496:TECTFE]2.0.CO;2|s2cid= 84868780|issn= 0022-3360|url-access= subscription}}
Emuella dalgarnoi Pocock, 1970

}}

Emuella is a genus of Cambrian trilobites of the family Emuellidae. Its fossils have been found in South Australia.

Etymology

The genus name means "little emu", and refers to Emu Bay, on Kangaroo Island, one of the sites where fossils of Emuella have been collected. The species epithet polymera is derived from Greek words πολύ -poly- meaning "many"; and μέρος -meros- meaning "part", for the many segmented thorax. E. dalgarnoi is named after R.C. Dalgarno, who discovered Balcoracania dailyi in the Flinders Ranges, near Blinman, South Australia.{{cite journal|last=Pocock|first=K.J.|year=1970|title=The Emuellidae, a new family of trilobites from the Lower Cambrian of South Australia|journal=Palaeontology|volume=13|pages=522–562}}

Description

It can be recognised by touching glabella and frontal border, and the sub-pentagonal head, as compared to, a short field between the front of the axis in the head or glabella and the border ridge, and a semi-circular headsheald in the sister-genus Balcoracania. Both emuellid genera share eye ridges that are positioned parallel to the frontal and lateral border of the head, prominent genal spines that are a smooth continuation of the lateral margin of the head, a prothorax of 6 segments, with the 5th and 6th merged and carrying large trailing spines. Both genera have in adulthood a highly variable but large number of segments of the opistothorax, although the largest number found in B. dailyi with 97 is much larger than in Emuella (52).

References

Further information

{{cite book

| chapter = Burgess Shale-type Localities: The global picture

| author = Hagadorn, J.W.

| editor = Bottjer, D.J. |editor2=W. Etter |editor3=J.W. Hagadorn |editor4=C.M. Tang

| title=Exceptional Fossil Preservation -- A Unique View on the Evolution of Marine Life

| publisher=Columbia University Press

| year=2002

| isbn =0231102542

}}

{{cite web

|author1=Greg Edgecombe |author2=the Australian Museum

|name-list-style=amp | title=Australian Trilobites: A Species List and Bibliography

| url=http://www.austmus.gov.au/palaeontology/research/trilobites03.htm? | archive-url=https://web.archive.org/web/20080428044233/https://www.austmus.gov.au/palaeontology/research/trilobites03.htm

| archive-date=April 28, 2008

| url-status=dead

}}