Acritarche

The acritarches are Microfossile S with organic wall, i.e. Palynomorphe S, to which it is not possible to allot a biological affinity with certainty. The name Acritarche drift of the Greek akritos , meaning dubious or confused, and of arch , meaning origin. The Acritarche term was introduced for the first time by W.R. Evitt in 1963. One could caricature the acritarches as being all the palynomorphes which were put aside in the palynologic preparations (blades that under the microscope the specialists in Palynologie study) after having carried out all the other identifications. It is certain that various organizations are gathered under the acritarche term, which is thus a polyphyletic group. Some are probably Kyste S of Dinoflagellé S too badly preserved to be correctly identified, others belong without any doubt to the green Algue S and still of others strongly some Prasinophycée S. the acritarches resemble are known since the Précambrien (oldest known are gone back to 1,5 billion years), they are abundant during the Paléozoïque and then very strongly regress and disappear almost completely thereafter.

The large majority of the acritarches are found in Sédiment S sailors and/or are associated at marine organizations. In addition according to their morphology, their distribution, and their composition, the majority of the acritarches are supposed to be Phytoplancton and were thus at the base of the food chain of the marine ecosystem during the Protérozoïque and the Paléozoïque.

External bond

CIMP - International commission of the microflora of Paleozoic the

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