Sarcopterygii

The term Sarcoptérygiens (of the Greek , sarx , flesh, fleshy and pteryx , fin, wing) indicates the class osseous fish including/understanding the Cœlacanthe S and the Dipneustes (fish with lungs).

The Sarcoptérygiens present the first anatomical elements marking the evolution towards the Tétrapode S. In phylogenetic Classification, the Tétrapode S belong to the Sarcoptérygiens , without what this group would be Paraphylétique.

Classification

Synapomorphie S of the group

Fin S lobed and articulation monobasale. Each lobe is supported by an internal skeleton of bones which are articulated between them then with a robust pectoral or pelvic belt.
Joint intracrânial: fissure dividing cranium into two halves, former and posterior.
Muscle S which can drive the osseous rays of the fin independently from/to each other.
true enamel on the teeth.
Fifth and last arc branchial sticking ventralement on the last but one.

Orders

classify Sarcopterygii

subclass Coelacanthimorpha (Cœlacanthe)

order Coelacanthiformes (Coelacanth)

subclass Dipnoi (Dipneustes)

superorder Ceratodontimorpha (Dipneuste)

order Ceratodontiformes (Dipneuste of Australia)
order Lepidosireniformes (American Southern Dipneuste)

Evolutionary history of the group

the group inherits higher fish a jaw articulated (jawbone), and the teeth cover enamel.
the even fins evolve to the shape of member: the basal fastener is reduced to only one element (femur, scapula and humérus), and of the muscles allow the articulation independent of the rays (fingers).
the lung (swim bladder/air bag) becomes functional and provided with cells.

The last evolution of the type is the birth of the neck: the fastener of the forelimb (scapular girdles) is detached from the head, and the first cervical vertebrae specialize to allow an articulation of the cou.z

Place du groups in the reign Animal

External bonds

Simple: Sarcopterygii

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