Acanthodii


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Acanthodii

[ə‚kan′thō·dē‚ī]
(paleontology)
A class of extinct fusiform fishes, the first jaw-bearing vertebrates in the fossil record.
References in periodicals archive ?
The Acanthodii group of fish are also known as 'spiny sharks' owing to their appearance and, from what we know to date, they only lived during the Palaeozoic Era and reached their maximum level of diversity in the Devonic period.
Some other fossil fishes also have a nodular ultrasculpture on their scales but it differs strongly in measurements (the nodes being very fine: 1-2 [micro]m in Acanthodii, see Beznosov 2001; 2.