Tariccoia arrusensis Temporal range:
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Tariccoia arrusensis, 21 mm, from Sardegna, Italy | |
Scientific classification | |
Kingdom: | |
Phylum: | |
Order: | |
Family: | †
Liwiidae
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Genus: | †Tariccoia Hammann, 1990
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Type species | |
†Tariccoia arrusensis Hammann, 1990
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Other species | |
T. tazagurtensis |
Tariccoia is a genus of nektaspid arthropods belonging to the family Liwiidae, known from fossils found in Ordovician strata in Sardinia and Morocco. It is between 2.5 centimetres (0.98 in) and 6 centimetres (2.4 in) long. It has a headshield (or cephalon) wider than the tailshield ( pygidium), and in between them three (or four?) thoracic body segments ( somites).
The name of the genus references the Sardinian paleontologist M. Taricco. The species was named after the Riu is Arrus Member, the deposit in which it was found. [1]
Tariccoia arrusensis is between 2.5 and 6 cm along the axis, [2] almost half a wide as long. The dorsal exoskeleton consists of a cephalon, a pygidium and two or three thoracic somites with articulating half-rings, all non-calcified. The cephalon is sub-semicircular, widest near the rounded genal angles. The cephalon is wider than the pygidium. Eyes are absent. Antennas are not known. The body is constricted at the two or three thoracic somites, so the animal gives the impression to have a waist. The pygidium is widest before midlength. The pygidium has a mid-ridge. [1]
T. arrusensis has been collected from the Upper Ordovician ( Sandbian to Katian) Riu is Arrus Member, Monte Argentu Formation, Sardinia, Italy. [1] T. tazagurtensis has been collected from the Fezouata Formation of Morocco dating to the Early Ordovician ( Tremadocian). [4]
Tariccoia arrusensis is thought to have lived in a restricted reduced oxygen marine environment close to shore such as a lagoon or a bay in what was then the cold high-latitude margin of southern Gondwana, where it was locally abundant alongside macroscopic algae. Tariccoia tazagurtensis also lived in cold waters in high-latitude southern Gondwana, but it was an extremely rare member of the fauna and lived in open shallow-marine conditions. [4]
Tariccoia arrusensis Temporal range:
| |
---|---|
![]() | |
Tariccoia arrusensis, 21 mm, from Sardegna, Italy | |
Scientific classification | |
Kingdom: | |
Phylum: | |
Order: | |
Family: | †
Liwiidae
|
Genus: | †Tariccoia Hammann, 1990
|
Type species | |
†Tariccoia arrusensis Hammann, 1990
| |
Other species | |
T. tazagurtensis |
Tariccoia is a genus of nektaspid arthropods belonging to the family Liwiidae, known from fossils found in Ordovician strata in Sardinia and Morocco. It is between 2.5 centimetres (0.98 in) and 6 centimetres (2.4 in) long. It has a headshield (or cephalon) wider than the tailshield ( pygidium), and in between them three (or four?) thoracic body segments ( somites).
The name of the genus references the Sardinian paleontologist M. Taricco. The species was named after the Riu is Arrus Member, the deposit in which it was found. [1]
Tariccoia arrusensis is between 2.5 and 6 cm along the axis, [2] almost half a wide as long. The dorsal exoskeleton consists of a cephalon, a pygidium and two or three thoracic somites with articulating half-rings, all non-calcified. The cephalon is sub-semicircular, widest near the rounded genal angles. The cephalon is wider than the pygidium. Eyes are absent. Antennas are not known. The body is constricted at the two or three thoracic somites, so the animal gives the impression to have a waist. The pygidium is widest before midlength. The pygidium has a mid-ridge. [1]
T. arrusensis has been collected from the Upper Ordovician ( Sandbian to Katian) Riu is Arrus Member, Monte Argentu Formation, Sardinia, Italy. [1] T. tazagurtensis has been collected from the Fezouata Formation of Morocco dating to the Early Ordovician ( Tremadocian). [4]
Tariccoia arrusensis is thought to have lived in a restricted reduced oxygen marine environment close to shore such as a lagoon or a bay in what was then the cold high-latitude margin of southern Gondwana, where it was locally abundant alongside macroscopic algae. Tariccoia tazagurtensis also lived in cold waters in high-latitude southern Gondwana, but it was an extremely rare member of the fauna and lived in open shallow-marine conditions. [4]