Curviacus
Ediacaran fossil
From Wikipedia, the free encyclopedia
Curviacus is a genus of Ediacaran organism of uncertain lineage that displays a modular body plan consisting of crescent-shaped chambers. It contains a single species, Curviacus ediacaranus.
Shen et al., 2017
| Curviacus Temporal range: Late Ediacaran ~ | |
|---|---|
Scientific classification  | |
| Domain: | Eukaryota |
| Clade: | incertae sedis |
| Informal group: | †Palaeopascichnida |
| Genus: | †Curviacus Shen et al., 2017 |
| Species: | †C. ediacaranus |
| Binomial name | |
| †Curviacus ediacaranus Shen et al., 2017 | |
Etymology
Description
These fossils occur on bituminous limestone on the bedding surface. The fossilized specimen has calcispar walls with the inner chambers filled with micrite.[1] The walls are raised because the calcispar does not erode as easily. C. ediacaranus is a slightly oblong macrofossil that ranges from 5–14 cm in length. It is characterized by its curved or crescent-shaped chambers that occur arranged in a series with the chambers sharing walls. All of the chambers are convex in the same direction. Each chamber is narrow ranging ~1-3mm in width. Chamber length can be consistent or inconsistent. Inconsistencies can give a false impression of branching.[1] Additionally, the walls of the chambers sometimes converge laterally.
Phylogeny
The phylogeny of this fossil is not yet known. Some scientists believe the genus to be a coralline algal or fungal stem group.[1]
Occurrence
C. ediacaranus is from the late Ediacaran. The fossil C. ediacaranus has been found in the Shibantan Member of the Dengying Formation.[1] The Shibantan Member is the bituminous limestone section of the formation.[2] It is unusual for Ediacaran biota to be preserved in limestone. As such, C. ediacaranus is the only Palaeopascichnus fossil to be reported from carbonate rock rather than siliclastic rock.[1] This special type of fossilization allows for 3-dimensional analysis.[1]
