Andiva
| Andiva | ||||||||
|---|---|---|---|---|---|---|---|---|
Fossil from Andiva ivantsovi |
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| Temporal occurrence | ||||||||
| Ediacarium | ||||||||
| 555 million years | ||||||||
| Locations | ||||||||
| Systematics | ||||||||
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| Scientific name | ||||||||
| Andiva | ||||||||
| Fedonkin , 2002 | ||||||||
| Art | ||||||||
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Andiva is an extinct animal genus of the Ediacariums , which belongs tothe Proarticulata tribe (or to the clade Bilateriomorpha ).
etymology
Andiva is an acronym that was formed from the name of the Russian paleontologist Andrei Jurjewitsch Iwanzow ( Andiva = And rey Iva ntsov). The species name ivantsovi also honors the above-mentioned paleontologists.
Discovery and first description
Andiva ivantsovi was discovered on the winter coast (Зимний Берег) of the White Sea in Russia in 1977 . In 2002 it was raised to the rank of a new genus by Mikhail Alexandrowitsch Fedonkin and scientifically described.
Occurrence
In addition to the type locality on the winter coast, fossils of Andiva also occur in South Australia .
description
Andiva reached a length of 60 to 100 millimeters, the width of the bilaterally symmetrical fossil measured 40 to 55 millimeters. The front end was slightly wider than the rear end. The front end was surrounded by a smooth, hairband-like hem. As with papillary ridges, the surface was traversed by fine ribs and sutures. This quilted structure resembles an air mattress with narrow, tightly packed chambers. However, the transverse ribs do not run continuously through both wings, but are slightly offset from one another on the central axis due to sliding reflection . This characteristic is also shared by other representatives of the Proarticulata tribe.
In his original reconstruction, Fedonkin interpreted the papilla pattern as an armor-like shield, probably made of chitin or some other organic, non-mineralized substance, the task of which was to give protection to the animal crawling or gliding across the seabed while foraging for food. He interpreted the smooth front hem as an impression of soft tissue below the dorsal shield.
Socialization
Andiva often appears in company with other taxa of the Ediacaran biota :
Taxonomy
Morphologically, Andiva most closely resembles the genera Ovatoscutum and Chondroplon . Dickinsonia and other members of the Proarticulata tribe such as Archaeaspinus and Cyanorus are also likely to be more closely related.
In contrast to the usual assignment of Andiva to the class of Cephalozoa , Jerzy Dzik places the taxon within the Proarticulata in the class of Dipleurozoa . He regards the genus Chondroplon as the closest relative. The genera Archaeaspinus , Praecambridium , Vendia and Yorgia are also relatively close . A common feature of all of these fossils is a dorsal axis chamber bent to the right. Dzik already regards the genera Spriggina and Dickinsonia as further away.
Dzik suggests the following cladogram for the taxonomic position of Andiva :
| Dickinsonia | |||||||||||||||||||
| Dipleurozoa | |||||||||||||||||||
| Spriggina | |||||||||||||||||||
| Archaeaspinus , Praecambridium , Vendia and Yorgia | |||||||||||||||||||
| Andiva , Chondroplon | |||||||||||||||||||
Individual evidence
- ↑ a b c d Fedonkin, MA: Andiva ivantsovi gen. Et sp. n. and related carapace ‐ bearing Ediacaran fossils from the Vendian of the Winter Coast, White Sea, Russia . In: Italian Journal of Zoology . tape 69 (2) , 2002, pp. 175-181 , doi : 10.1080 / 11250000209356456 .
- ↑ Gehling, JGund Droser, ML: Textured Organic Surfaces Associated with the Ediacaran biota in South Australia . In: Earth Science Reviews . tape 96 (3) , 2009, pp. 196–206 , doi : 10.1016 / j.earscirev.2009.03.002 .
- ^ A b Dzik, J .: Anatomical Information Content in the Ediacaran Fossils and Their Possible Zoological Affinities . In: Integrative and Comparative Biology . tape 43 (1) , 2003, p. 114-126 , doi : 10.1093 / icb / 43.1.114 .
- ^ Ivantsov, AY: New Proarticulata from the Vendian of the Arkhangel'sk Region . In: Paleontological Journal . tape 38 (3) , 2004, p. 247-253 .
