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Evolution of brachiopods. The origin of the brachiopods is uncertain; they either arose from reduction of a multi-plated tubular organism, or from the folding of a slug-like organism with a protective shell on either end. Since their Cambrian origin, the phylum rose to a Palaeozoic dominance, but dwindled during the Mesozoic.
Brachiopod. Brachiopods (/ ˈbrækioʊˌpɒd /), phylum Brachiopoda, are a phylum of trochozoan animals that have hard "valves" (shells) on the upper and lower surfaces, unlike the left and right arrangement in bivalve molluscs. Brachiopod valves are hinged at the rear end, while the front can be opened for feeding or closed for protection.
Evolution of fish. The Devonian period (419–359 Mya), also known as the Age of Fishes, saw the development of early sharks, armoured placoderms and various lobe-finned fish, including the tetrapod transitional species. The evolution of fish began about 530 million years ago during the Cambrian explosion. It was during this time that the early ...
See text. Bryozoa (also known as the Polyzoa, Ectoprocta or commonly as moss animals) [6] are a phylum of simple, aquatic invertebrate animals, nearly all living in sedentary colonies. Typically about 0.5 millimetres (⁄64 in) long, they have a special feeding structure called a lophophore, a "crown" of tentacles used for filter feeding.
The evolution of the molluscs is the way in which the Mollusca, one of the largest groups of invertebrate animals, evolved. This phylum includes gastropods, bivalves, scaphopods, cephalopods, and several other groups. The fossil record of mollusks is relatively complete, and they are well represented in most fossil-bearing marine strata.
L. waikatoensis Pen, 1930. Synonyms. Ligula, Ligularius, Lingularius, Pharetra. Lingula is a genus of brachiopods within the class Lingulata. Lingula or forms very close in appearance have existed possibly since the Cambrian. Like its relatives, it has two unadorned organo-phosphatic valves and a long fleshy stalk.
List of living brachiopod species. The following is a taxonomy of extant (living) Brachiopoda by Emig, Bitner & Álvarez (2019). There are over 400 living species and over 120 living genera of brachiopods classified within 3 classes and 5 orders, listed below. Extinct groups are not listed. [1]
A Devonian spiriferid brachiopod from Ohio which served as a host substrate for a colony of hederellids. Spiriferida is an order of extinct articulate brachiopod fossils which are known for their long hinge-line, which is often the widest part of the shell. In some genera (e.g. Mucrospirifer) it is greatly elongated, giving them a wing-like ...