Xenacanthida

Expleuracanthus gaudri, live reconstruction

• Europe
• North and South America
• Australia

The Xenacanthiformes are an extinct group of externally haiähnlicher cartilaginous fishes that occurred from the Early Devonian to the Upper Triassic in inland waters. They are therefore referred to as " freshwater sharks". Fossils of these fish are in Europe, North and South America and Australia have been found.

Features

The Xenacanthiformes had the typical streamlined, elongated body of the sharks, but a straight, long, occupied with a Flossensaum from coalesced dorsal and anal fin tail ( diphycerker tail). At the top rear of the skull was a long head sting. They had five different lengths of gill arches. Some fossil specimens can be found just behind the pelvic fins long paired movable appendages. These are the Pterygopodien or Klaspern of the males, retaining members, which was transferred at mating, the female fixed to the seed.

System

• Diplodoselachidae Dick, 1981 Diplodoselache

• Anodontacanthus
• Antarctilamna
• Branson Ella
• Diacranodus
• Expleuracanthus
• Orthacanthus
• Phricacanthus
• Platyacanthus
• Pleuracanthus
• Triodus
• Xenacanthus
• Bohemiacanthus