Swartpuntia
Encyclopedia
Swartpuntia is a monospecific genus
of erniettomorph
from the terminal Ediacaran
period, with at least three quilted, leaf-shaped petaloids — probably five or six. The petaloids comprise vertical sheets of tubes filled with sand. Swartpuntia specimens range in length from 12 to 19 cm, and in width from 11.5 to 140 cm. The margin is serrated, with a 1 mm wide groove. A 14 mm wide stem extends down the middle, tapering towards the top, and stopping 25 mm from the tip. The stem has a V shaped ornamentation on it. The original fossil
s were found at, and named after, the Swartpunt farm between Aus and Rosh Pinah in Namibia
. The name Swartpunt means black point referring to the colour of the rocks. The germsi species name honours Gerard Germs, who studied the Nama formation of geological beds.
They are preserved in sandstone beds in the Spitzkopf Member from the Nama formation, which lie above an ash bed dated at 543±1 million years old, and occur until the very end of the Ediacaran beds in this locality (Narbonne et al. 1997): the start of the Cambrian
period is dated . Whilst Swartpuntia has since been found in south-western North America
and the Carolina Terrane , it does not appear to have had a global distribution — indeed, its seemingly limited range has been used to provide palæogeographical
reconstruction (Hagadorn & Waggonner 2000).
The shape of Swartpuntia resembles other rangeomorph
s Pteridinium
and Charniodiscus
, both frond
s with alternating
segments; interestingly, the segments' microstructure resembles that of Dickinsonia
. This combination of features suggests close relationships between the Ediacaran biota, and lends credence to their membership of a separate phylum (Seilacher
's Vendobionta). Mark McMenamin
has inferred a photosymbiotic lifestyle for Swartpuntia, and this seems likely considering its shallow water habitat, tree-like shape and lack of apparent heterotrophic feeding structures.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of erniettomorph
Erniettomorph
The Erniettomorphs are a form of Ediacaran fossil consisting of rows of airbed-like tubes arranged along a midline with a glide symmetry. Representative genera include Ernietta, Phyllozoon, Pteridinium, Swartpuntia and possibly Dickinsonia....
from the terminal Ediacaran
Ediacaran
The Ediacaran Period , named after the Ediacara Hills of South Australia, is the last geological period of the Neoproterozoic Era and of the Proterozoic Eon, immediately preceding the Cambrian Period, the first period of the Paleozoic Era and of the Phanerozoic Eon...
period, with at least three quilted, leaf-shaped petaloids — probably five or six. The petaloids comprise vertical sheets of tubes filled with sand. Swartpuntia specimens range in length from 12 to 19 cm, and in width from 11.5 to 140 cm. The margin is serrated, with a 1 mm wide groove. A 14 mm wide stem extends down the middle, tapering towards the top, and stopping 25 mm from the tip. The stem has a V shaped ornamentation on it. The original fossil
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...
s were found at, and named after, the Swartpunt farm between Aus and Rosh Pinah in Namibia
Namibia
Namibia, officially the Republic of Namibia , is a country in southern Africa whose western border is the Atlantic Ocean. It shares land borders with Angola and Zambia to the north, Botswana to the east and South Africa to the south and east. It gained independence from South Africa on 21 March...
. The name Swartpunt means black point referring to the colour of the rocks. The germsi species name honours Gerard Germs, who studied the Nama formation of geological beds.
They are preserved in sandstone beds in the Spitzkopf Member from the Nama formation, which lie above an ash bed dated at 543±1 million years old, and occur until the very end of the Ediacaran beds in this locality (Narbonne et al. 1997): the start of the Cambrian
Cambrian
The Cambrian is the first geological period of the Paleozoic Era, lasting from Mya ; it is succeeded by the Ordovician. Its subdivisions, and indeed its base, are somewhat in flux. The period was established by Adam Sedgwick, who named it after Cambria, the Latin name for Wales, where Britain's...
period is dated . Whilst Swartpuntia has since been found in south-western North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
and the Carolina Terrane , it does not appear to have had a global distribution — indeed, its seemingly limited range has been used to provide palæogeographical
Palaeogeography
Palaeogeography is the study of what the geography was in times past. It is most often used about the physical landscape, although nothing excludes its use in reference to the human or cultural environment...
reconstruction (Hagadorn & Waggonner 2000).
The shape of Swartpuntia resembles other rangeomorph
Rangeomorph
The Rangeomorphs are a form taxon of frondose Ediacaran fossils that are united by a similarity to Rangea. Some workers, e.g. Pflug and Narbonne, suggest that a natural taxon Rangeomorpha may include all similar-looking fossils....
s Pteridinium
Pteridinium
Pteridinium is an erniettomorph found in a number of Precambrian deposits worldwide. It is a member of the Ediacaran biota.-Body plan:It has a three-lobed body which is generally smashed flat such that only two lobes are visible. Each lobe consists of a number of parallel ribs extending back to the...
and Charniodiscus
Charniodiscus
Charniodiscus is an Ediacaran fossil that was probably a stationary filter feeder that lived anchored to a sandy sea bed. The organism had a holdfast, stalk and frond. The holdfast was bulbous shaped, and the stalk was flexible. The frond was segmented and had a pointed tip...
, both frond
Frond
The term frond refers to a large, divided leaf. In both common usage and botanical nomenclature, the leaves of ferns are referred to as fronds and some botanists restrict the term to this group...
s with alternating
segments; interestingly, the segments' microstructure resembles that of Dickinsonia
Dickinsonia
Dickinsonia is an iconic fossil of the Ediacaran biota. It resembles a bilaterally symmetrical ribbed oval. Its affinities are presently unknown; most interpretations consider it to be an animal, although others suggest it may be fungal, or a member of an "extinct kingdom".-Species variety:A...
. This combination of features suggests close relationships between the Ediacaran biota, and lends credence to their membership of a separate phylum (Seilacher
Adolf Seilacher
Adolf "Dolf" Seilacher is a German palaeontologist who has made major contributions to evolutionary and ecological palaeobiology in a career stretching over 60 years. He won the Crafoord Prize in 1992, the Paleontological Society Medal in 1994 and the Palaeontological Association's Lapworth Medal...
's Vendobionta). Mark McMenamin
Mark McMenamin
Mark McMenamin is a tenured professor of geology at Mount Holyoke College. His research is primarily focused on paleontology, particularly the Ediacaran biota....
has inferred a photosymbiotic lifestyle for Swartpuntia, and this seems likely considering its shallow water habitat, tree-like shape and lack of apparent heterotrophic feeding structures.