Valdiviathyris

Valdiviathyris is a genus of craniate brachiopods that has changed little since the Silurian, from when fossils are known.[2] The extant species V. quenstedti is known from the late Eocene.[3][4] It was initially known only from the holotype collected from the southern Indian Ocean, near Île Saint-Paul, at a depth of 672 metres (2,205 ft).[4] The specimen is considered to be adolescent and has a thin (0.1 mm thick) calcareous dorsal valve. This has an irregular conical shape, with the tip (or apex) not coinciding with the middle, and is on the outside only adorned by growth lines. On the inside it has pits (or punctae) that branch into four or five canals further to the outside. More recent specimens have been found near New Zealand. As long as no fossils of Vadiviathyris are found dating between the Silurian and the Eocene, this genus can be regarded a Lazarus taxon.[2]

Valdiviathyris
Temporal range: Silurian–Recent
Scientific classification
Kingdom: Animalia
Clade: Lophophorata
Phylum: Brachiopoda
Class: Craniata
Order: Craniida
Family: Craniidae
Genus: Valdiviathyris
Helmcke, 1940 [1]
Type species
Valdiviathyris quenstedti
Helmcke, 1940 [1]
Species
  • V. quenstedti Helmcke, 1940 Late Eocene to recent
  • V. bicornis Holmer, Popov & Bassett, 2013 Silurian

References
  1. Christian Emig (2013). Emig CC (ed.). "Valdiviathyris Helmcke, 1940". World Brachiopoda database. World Register of Marine Species. Retrieved October 8, 2013.
  2. Holmer, Lars E.; Popov, Leonid; Bassett, Michael G. (2013). "Silurian Craniide brachiopods from Gotland". Palaeontology. 56 (5): 1029–1044.
  3. Jeffrey H. Robinson & Daphne E. Lee (2007). "The recent and Paleogene craniid brachiopod, Valdiviathyris quenstedti Helmcke, 1940". Systematics and Biodiversity. 5 (1): 123–131. doi:10.1017/S1477200006002179.
  4. A. J. Rowell (1961). "The brachiopod genus Valdiviathyris Helmcke, 1940" (PDF). Palaeontology. 4 (4): 542–545.


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