#placodermi

Gemuendina

Gemuendina — це плакодерма з ряду Rhenanida, що мешкала в морях Німеччини раннього девону. За життя Gemuendina нагадувала ската з задертою головою або зіркогляда (Uranoscopus). Типовий вид – Gemuendina stuertzi.

Повний текст на сайті "Вимерлий світ":

Dunkleosteus

Дунклеостей (лат. Dunkleosteus) – рід вимерлих панцирних риб ряду артродіри (Arthrodira) класу плакодерм (Placodermi), що жили в девонському періоді, 415-360 млн років тому. Представники роду відносились до найбільших морським хижакам свого часу. Викопні рештки були виявлені в Марокко, Бельгії, Польщі та Північній Америці. Точний розмір дунклеостея визначити важко: зазвичай від нього зберігаються тільки кістки голови,…

Повний текст на сайті "Вимерлий світ":

Savage 10 metre fish of the Silurian and Devonian

Heavily armoured piscine torpedoes with fierce teeth roamed the oceans in the early days of fishes, in fact the Devonian era is called the age of fishes by palaeontologists as they had a huge burst of speciation and diversified to fill most marine ecological niches during this time. The now extinct (fortunately) class known as placodermi (plate skin in Greek) was the apex predator of these long gone waters, and thrived from 438 to 358 million years ago, dying out at the end Devonian mass extinction (one of the lesser ones).

They were amongst the first fish with proper articulated jaws, and evolved the structure that passed on to modern fishes. They also developed pelvic fins, which eventually changed into legs as the first tetrapod fish came onto land in the late Devonian, and the first live birth was discovered in a fossil from Western Australia (which pushed back the history of live births by 200 million years). Many were bottom dwelling predators in both fresh and salt water in the shallow seas, though some herbivorous species existed alongside them.

We illustrate the post with a herbivorous genus called Bothriolepis around a metre long, and the head of a large species of Dunkleosteus, from the late Devonian. Only the armoured front end of these fishes often survives the vagaries of fossilisation.

Loz

Reuters: “An international team of scientists in China has discovered what may be the earliest known creature with a distinct face, a 419 million-year-old fish that could be a missing link in the development of vertebrates.

The fossil find in China’s…