''Albumares brunsae'' is a tri-radially symmetrical fossil animal that lived in the late
Ediacaran
The Ediacaran Period ( ) is a geological period that spans 96 million years from the end of the Cryogenian Period 635 million years ago (Mya), to the beginning of the Cambrian Period 538.8 Mya. It marks the end of the Proterozoic Eon, and th ...
seafloor. It is a member of the extinct group
Trilobozoa
''Trilobozoa'' (meaning "three-lobed animals") is a phylum of extinct mobile animals that were originally classified into the Cnidaria. The basic body plan of ''Trilobozoa'' is often a tri-radial or radial sphere-shaped form with lobes radiating ...
.
Etymology
The generic name ''Albumares'' derives from the Latin ''Mare Album'' (
White Sea
The White Sea (russian: Белое море, ''Béloye móre''; Karelian and fi, Vienanmeri, lit. Dvina Sea; yrk, Сэрако ямʼ, ''Serako yam'') is a southern inlet of the Barents Sea located on the northwest coast of Russia. It is su ...
).
The specific name honors Elizabeth P. Bruns, an early 20th-century Russian geologist noted for her extensive and important research of the
Upper Precambrian stratigraphy of
European Russia
European Russia (russian: Европейская Россия, russian: европейская часть России, label=none) is the western and most populated part of Russia. It is geographically situated in Europe, as opposed to the cou ...
.
Occurrence
Fossils of the ''Albumares brunsae'' are known from deposits on the Verkhovka formation on the
Syuzma River in the
Onega Peninsula
The Onega Peninsula is located in Arkhangelsk Oblast, Russia. It protrudes into the White Sea, with Onega Bay to the south-west, and Dvina Bay to the north-east. The length of the peninsula is about , and the width varies between and .
Geograp ...
of the White Sea,
Arkhangelsk Region
Arkhangelsk Oblast (russian: Арха́нгельская о́бласть, ''Arkhangelskaya oblast'') is a federal subject of Russia (an oblast). It includes the Arctic archipelagos of Franz Josef Land and Novaya Zemlya, as well as the Solove ...
,
Russia
Russia (, , ), or the Russian Federation, is a List of transcontinental countries, transcontinental country spanning Eastern Europe and North Asia, Northern Asia. It is the List of countries and dependencies by area, largest country in the ...
.
There are reports about ''Albumares'' sp. from the Rawnslay Quartzite,
Flinders Ranges
The Flinders Ranges are the largest mountain range in South Australia, which starts about north of Adelaide. The ranges stretch for over from Port Pirie to Lake Callabonna.
The Adnyamathanha people are the Aboriginal group who have inhabi ...
in the
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 ...
, but photographs or description of these fossils have not yet been published.
Description
''Albumares'' fossils are preserved as negative, low impressions on the bases of sandstone beds. The fossil exhibits circular,
trefoil
A trefoil () is a graphic form composed of the outline of three overlapping rings, used in architecture and Christian symbolism, among other areas. The term is also applied to other symbols with a threefold shape. A similar shape with four rin ...
-like (three-lobe) form, and is covered by three dendritic-branched furrows and three oval ridges that radiate from the center. The lobes are twisted into weak spirals.
The diameters of known specimens vary from 8 to 15 millimeters.
Reconstruction and affinity
''Albumares'' was originally described by
Mikhail Fedonkin
Academician Mikhail Aleksandrovich Fedonkin (russian: Михаи́л Алекса́ндрович Федо́нкин; born June 19, 1946) is a Russian paleontologist specializing in documentation of the earliest animals' body fossils, tracks, an ...
as a free-swimming
scyphozoa
The Scyphozoa are an exclusively marine class of the phylum Cnidaria, referred to as the true jellyfish (or "true jellies").
The class name Scyphozoa comes from the Greek word ''skyphos'' (), denoting a kind of drinking cup and alluding to the ...
n
jellyfish
Jellyfish and sea jellies are the informal common names given to the medusa-phase of certain gelatinous members of the subphylum Medusozoa, a major part of the phylum Cnidaria. Jellyfish are mainly free-swimming marine animals with umbrella- ...
. The branched furrows on the fossil were interpreted as imprints of a system of internal radial canals and tentacles along the outer margin of the fossil, with the three oval ridges described as imprints of mouth lobes
or gonades.
Later, with the discovery of the closely related ''
Anfesta
''Anfesta stankovskii'' is a tri-radially symmetrical fossil animal that lived in the late Ediacaran (Vendian) seafloor. It is a member of the extinct group Trilobozoa.
Etymology
The generic and specific names of the ''Anfesta stankovskii'' hon ...
'' and with their seeming affinities to ''
Tribrachidium
''Tribrachidium heraldicum'' is a tri-radially symmetric fossil animal that lived in the late Ediacaran (Vendian) seas. In life, it was hemispherical in form. ''T. heraldicum'' is the best known member of the extinct group Trilobozoa.
Etymology
...
'', Fedonkin appointed these animals to the
Trilobozoa
''Trilobozoa'' (meaning "three-lobed animals") is a phylum of extinct mobile animals that were originally classified into the Cnidaria. The basic body plan of ''Trilobozoa'' is often a tri-radial or radial sphere-shaped form with lobes radiating ...
, an extinct group of the tri-radially symmetrical coelenterate-like animals that only superficially resembled cnidarians.
Originally, Trilobozoa was established as a class in the phylum
In biology, a phylum (; plural: phyla) is a level of classification or taxonomic rank below kingdom and above class. Traditionally, in botany the term division has been used instead of phylum, although the International Code of Nomenclature f ...
Coelenterata
Coelenterata is a term encompassing the animal phyla Cnidaria (coral animals, true jellies, sea anemones, sea pens, and their relatives) and Ctenophora (comb jellies). The name comes , referring to the hollow body cavity common to these two phyl ...
, but since Coelenterata has been divided into two separate phyla, Cnidaria
Cnidaria () is a phylum under kingdom Animalia containing over 11,000 species of aquatic animals found both in freshwater and marine environments, predominantly the latter.
Their distinguishing feature is cnidocytes, specialized cells that th ...
and Ctenophora
Ctenophora (; ctenophore ; ) comprise a phylum of marine invertebrates, commonly known as comb jellies, that inhabit sea waters worldwide. They are notable for the groups of cilia they use for swimming (commonly referred to as "combs"), an ...
, Trilobozoa itself has been promoted to the rank of phylum.
According to the latest research, ''Albumares'' was a soft-bodied benthic
The benthic zone is the ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers. The name comes from ancient Greek, βένθος (bénthos), meaning "t ...
organism that temporarily attached (but did not adhere) to the substrate of its habitat (microbial mats
A microbial mat is a multi-layered sheet of microorganisms, mainly bacteria and archaea, or bacteria alone. Microbial mats grow at interfaces between different types of material, mostly on submerged or moist surfaces, but a few survive in deserts. ...
). This fossil typically displays as an imprint of the upper side of the animal's body, and often some elements of its internal structure can be discerned. The branched furrows on the fossil are imprints of radial grooves on the surface of the animal, while the three ridges in the central part of the fossil are imprints of cavities within the body. Presumably, this system of grooves and cavities could be related to the collection and digestion of food particles.[
]
See also
* List of Ediacaran genera
This is a list of all described Ediacaran genera, including the Ediacaran biota. It contains 227 genera.
References
{{reflist, 30em
*
Ediacaran
The Ediacaran Period ( ) is a geological period that spans 96 million years from the end o ...
References
{{Taxonbar, from=Q1934918
Ediacaran life
Trilobozoa
White Sea fossils
Fossil taxa described in 1976