''Avalofractus abaculus'' is a frond-like

rangeomorph The rangeomorphs are a form taxon of frondose Ediacaran fossils that are united by a similarity to ''Rangea''. Some researchers, such as Pflug and Narbonne, suggest that a natural taxon Rangeomorpha may include all similar-looking fossils. Rang ...

fossil described from the

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 t ...

of the

Trepassey Formation The Trepassey Formation is a geologic formation that crops out in Newfoundland. It preserves fossils dating back to the Ediacaran period. See also * List of fossiliferous stratigraphic units in Newfoundland and Labrador This is a list of f ...

, Spaniard's Bay,

Newfoundland Newfoundland and Labrador (; french: Terre-Neuve-et-Labrador; frequently abbreviated as NL) is the easternmost province of Canada, in the country's Atlantic region. The province comprises the island of Newfoundland and the continental region ...

Morphology

''Avalofractus'' displays a strongly

fractal In mathematics, a fractal is a geometric shape containing detailed structure at arbitrarily small scales, usually having a fractal dimension strictly exceeding the topological dimension. Many fractals appear similar at various scales, as il ...

body shape, with four levels of nearly perfectly self-similar, pinnate, alternate branches. It was about 5 cm long on average, with a 1 cm-diameter holdfast at the base of the frond. The stem length is from 1/3 to 1/2 that of the whole frond. It is quite similar to '' Rangea'', even if with distinct morphological differences that justify the creation of a new

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial n ...

(e.g. absence of subsidiary quilts, frond elements free to rotate independently instead of being attached to each other by a membrane).

Distribution

In contrast with other rangeomorphs, which have wide distributions, ''Avalofractus'' seems to have been an

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found els ...

species, being known only from the Spaniard's Bay deposits.

Reproduction

It has been suggested that ''Avalofractus'' could have been capable of

vegetative reproduction Vegetative reproduction (also known as vegetative propagation, vegetative multiplication or cloning) is any form of asexual reproduction occurring in plants in which a new plant grows from a fragment or cutting of the parent plant or spe ...

: loose fronds could have detached and grow, rather like a plant cutting. This could explain the mysterious lack of independent rangeomorph fronds smaller than 10 mm in the fossil record. A previous suggestion that ''Avalofractus'' younger individuals were encased in a sheath-like structure has been later dismissed.

References

Ediacaran life Rangeomorpha Ediacaran Canada Fossil taxa described in 2009 {{ediacaran-stub