Keretsa

Keretsa brutoni Temporal range: Ediacaran ~555  Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Scientific classification
Kingdom:	Animalia
(unranked):	Bilateria
Phylum:	incertae sedis (?Arthropoda) (?Proarticulata [1] )
Genus:	Keretsa
Species:	K. brutoni
Binomial name
Keretsa brutoni Ivantsov, 2017 [2]

Artist's reconstruction of K. brutoni as an arthropod, compared to individuals of Parvancorina

Keretsa brutoni is a fossil bilaterian from the Late Precambrian-aged Zimnie Gory Formation near Arkhangelsk Oblast, Russia, along the Winter coast of the White Sea. The first specimens were found in 2005. ^[2] This rounded oblong-shaped organism resembles Naraoia , in having its body divided into an anteriorly positioned headshield, and a trunkshield. A pair of antennae-like structures emanate from underneath the base of the headshield, and there are numerous oblique grooves along the trunkshield that suggest legs. ^[2]

References

1. A.Yu. Ivantsov (2017). "The most probable Eumetazoa among late Precambrian macrofossils". Invertebrate Zoology. 14 (2): 132. doi: 10.15298/invertzool.14.2.05 . The trunk axial part of Keretsa specimen is wrinkled, and we can not prove either an opposite or an alternate (as in the Proarticulata) arrangement of the half-segments.
2. A.Yu. Ivantsov (2017). "The most probable Eumetazoa among late Precambrian macrofossils". Invertebrate Zoology. 14 (2): 127–133. doi: 10.15298/invertzool.14.2.05 .