Aldanella

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Aldanella
Temporal range: Nemakit-Daldynian–Atdabanian [1]
Scientific classification
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Genus:
Aldanella

Vostokova, 1962
Binomial name
Aldanella remota
Shaler & Foerste, 1880
Species
  • A. attleborensisShaler & Foerste, 1880
  • A. costataMissarzhevsky, 1989
  • A. ibericaGubanov et al., 2004
  • A. kundaOpik, 1924
  • A. patelliformaBokova, 1990
  • A. patelliformisBokova, 1990
  • A. remotaBillings, 1872

Aldanella is an extinct paleozoic mollusc that was assigned to the Gastropod stem group [2] but may also belong to a paraphyletic "Monoplacophora".

Related Research Articles

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Anabarella is a species of bilaterally-flattened monoplacophoran mollusc, with a morphological similarity to the rostroconchs. Its shell preserves evidence of three mineralogical textures on its outer surface: it is polygonal near the crest of the shell, subsequently changing to both spiny and stepwise. Its internal microstructure is calcitic and semi-nacreous. Its name reflects its provenance from Anabar, Siberia. It has been interpreted as ancestral to the rostroconchs, and has been aligned to the Helcionellidae.

The oesophageal pouches are a pair of pouches connected to the oesophagus of all molluscs, and represent a synapomorphy of the phylum.

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References

  1. Gubanov, Alexander P.; Peel, John S. (2003). "The early Cambrian helcionelloid mollusc Anabarella Vostokova". Palaeontology. 46 (5): 1073. doi: 10.1111/1475-4983.00334 .
  2. Budd, G. E.; Jensen, S. (2000). "A critical reappraisal of the fossil record of the bilaterian phyla". Biological Reviews of the Cambridge Philosophical Society. 75 (2): 253–95. doi:10.1111/j.1469-185X.1999.tb00046.x. PMID   10881389.