''Yuyuanozoon magnificissimi'' is the largest known

vetulicolia VetulicoliaThe taxon name, Vetulocolia, is derived from the type genus, ''Vetulicola'', which is a compound Latin word composed of ''vetuli'' "old" and ''cola'' "inhabitant". is a taxon (either phylum or subphylum in rank) encompassing several ex ...

n, with the holotype (and only known specimen) measuring about 202 millimeters in length.Palaeocritti - a guide to prehistoric animals Yuyuanozoon magnificissimi
/ref> In life, it would have been an egg-shaped animal with a long cylindrical tail. The body is divided into 6 segments, with a gill opening (that has gill filaments extending out from each opening) placed symmetrically on each side of every body segment starting at the second segment. The cylindrical tail is divided into 7 segments, and differs from the tails of all other known vetulicolians (not being flattened like vetulicolids like ''

Vetulicola ''Vetulicola'' is an extinct genus of marine animal from the Cambrian of China. It is the eponymous member of the enigmatic phylum Vetulicolia, which is of uncertain affinities but may belong to the deuterostomes. Description The type species ...

'', and not oar-like or leaf-like like those of the didazoonids like ''

Didazoon ''Didazoon haoae'' is an extinct species of vetulicolid vetulicolian described by Shu, et al. based on fossils found in the Qiongzhusi (Chiungchussu) Formation, Yu'anshan Member (Eoredlichia zone), Lower Cambrian, in the Dabanqiao area (Kunming) ...

'', and is unlike the tails of

banffozoa Banffidae is an extinct family of vetulicolians that is the only family of the order Banffiata and class Heteromorphida, also known as Banffozoa. It contains the genera ''Banffia'', '' Heteromorphus'', and ''Skeemella''. Banffids differ from vetu ...

ns like ''

Banffia ''Banffia'' is a genus of animals described from Middle Cambrian fossils. The genus commemorates Banff, Alberta, near where the first fossil specimens were discovered. Its placement in higher taxa is controversial. It is considered to be a memb ...

'' and ''

Skeemella ''Skeemella clavula'' is an elongate animal from what is now the Middle Cambrian Wheeler Shale lagerstätte, of Utah. It has been classified with the vetulicolians VetulicoliaThe taxon name, Vetulocolia, is derived from the type genus, '' Vetu ...

''). The details of the tail anatomy, and of the gill openings with gill filaments currently leave ''Y. magnificissimi'' as ''

incertae sedis ' () or ''problematica'' is a term used for a taxonomic group where its broader relationships are unknown or undefined. Alternatively, such groups are frequently referred to as "enigmatic taxa". In the system of open nomenclature, uncertainty ...

''.

Etymology

The generic name translates as "Animal of Yu Yuan," Yu Yuan being an ancient name for

Chengjiang County Chengjiang (; earlier Tchinkiang) is a city located in Yuxi, Yunnan Province, China, just north of Fuxian Lake. Administrative divisions Chengjiang City has 2 subdistricts and 4 townships. ;2 subdistricts * Fenglu () * Longjie () ;4 towns C ...

. The specific name, ''magnificissimi'', translates as "magnificent," in reference to the great size of the holotype.

References

*Chen, Feng, Ma, Li, (2003), A New Vetulicolian from the Early Cambrian Chengjiang Fauna in Yunnan of China Acta Geologica Sinica

Notes

Cambrian animals of Asia Vetulicolia enigmatic taxa Fossil taxa described in 2001 Prehistoric animal genera {{paleo-deuterostome-stub Cambrian genus extinctions

Etymology

See also

References

Notes