''Emuella'' is a genus of

trilobite Trilobites (; meaning "three lobes") are extinct marine arthropods that form the class Trilobita. Trilobites form one of the earliest-known groups of arthropods. The first appearance of trilobites in the fossil record defines the base of the At ...

s of the family Emuellidae. Its fossils have been found in

South Australia South Australia (commonly abbreviated as SA) is a state in the southern central part of Australia. It covers some of the most arid parts of the country. With a total land area of , it is the fourth-largest of Australia's states and territories ...

. 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).

Etymology

The genus name means "little emu", and refers to

Emu Bay Emu Bay may refer to *Emu Bay (South Australia), a bay ** Emu Bay, South Australia, a locality ** Emu Bay Shale, a geological formation associated with the above locality * Emu Bay (Tasmanian geographic feature), on the northwest coast ** Burnie, Ta ...

, on Kangaroo Island, one of the sites where fossils of ''Emuella'' have been collected. The species

epithet An epithet (, ), also byname, is a descriptive term (word or phrase) known for accompanying or occurring in place of a name and having entered common usage. It has various shades of meaning when applied to seemingly real or fictitious people, di ...

''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 Blinman is a locality incorporating two towns located in the Australian state of South Australia within the Flinders Ranges about north of the state capital of Adelaide. It is very small but has the claim of being the highest surveyed town in S ...

, South Australia.

References

Further information

* * * * * Cambrian trilobites Emuelloidea Trilobites of Oceania Redlichiida genera Fossil taxa described in 1970 Emu Bay Shale {{redlichiida-stub Cambrian genus extinctions