Isognomon Explained

(For the tree oyster mushroom, see Pleurotus ostreatus.)

Isognomon is a genus of marine bivalve mollusks which is related to the pearl oysters.

Isognomon is known in the fossil record from the Permian period to the Quaternary period (age range: 254.0 to 0.012 million years ago). Fossils of species within this genus have been found all over the world.[1]

Taxonomy

This genus is placed in the family Isognomonidae. However previous molecular phylogeny studies have shown that these tree oysters belong in the family Pteriidae.[2] [3]

Description

These oysters grow to be about 4.75inches in overall length, producing a highly irregular shell with a blue-gray and often heavily encrusted exterior but a smooth and pearly white interior. They use their byssus to completely immobilize themselves to the roots of mangrove trees, corals, and other substrates.[4] It is because of the preference for mangroves that these are sometimes called tree oysters[5]

Species

Extinct species

Extinct species within this genus include:[1]

Species brought into synonymy:

References

Notes and References

  1. http://www.fossilworks.org/cgi-bin/bridge.pl?a=taxonInfo&taxon_no=16730 Fossilworks
  2. Temkin, I. (2010) Molecular phylogeny of pearl oysters and their relatives (Mollusca, Bivalvia, Pterioidea), BMC Evolutionary Biology 10:342
  3. Coan, E. V.; Valentich-Scott, P. (2012). Bivalve seashells of tropical West America. Marine bivalve mollusks from Baja California to northern Peru. 2 vols, 1258 pp
  4. Book: Arthur Peter Hoblyn Oliver. Guide to Seashells of the World. registration. 2004. Firefly . 978-1-55297-943-3. 300.
  5. https://www.papuaweb.org/dlib/tema/kamoro/muller-sda/12.rtf Papuaweb