Palaeocentrotidae
| Palaeocentrotidae | ||||||||||||
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Palaeocentrotus boeggildi |
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| Temporal occurrence | ||||||||||||
| Ypresian (Lower Eocene) to Rupelian (Lower Oligocene) | ||||||||||||
| 56 to 28.1 million years | ||||||||||||
| Locations | ||||||||||||
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Palaeocentrotidae | ||||||||||||
| Bonde , 1966 |
The Palaeocentrotidae are an extinct fish family from the order of gloss Fishy (Lampriformes). They are closely related to the recent sail carriers (Veliferidae) and together with them form the suborder Veliferoidei.
features
Like the sail carriers, the Palaeocentrotidae are high-backed, laterally strongly flattened fish. The head is relatively large with a high crest (supraoccipital crest). The mouth is large and toothless. The coracoid is not enlarged on the abdomen. The spine consists of 29 to 32 vertebrae. Ribs are poorly developed. The anterior section of the dorsal fin consists of a crescent-shaped lobe, which is supported by six soft rays and is separated from the rest of the dorsal fin by an indentation. The middle section of the dorsal fin is carried by eight or nine hard rays, the rear by about 20 soft rays. The anal fin is supported by five or six short hard rays and about 20 soft rays. The pectoral fins are small, the pelvic fins are long. The caudal fin is rounded and is supported by 10 or 12 fin rays. The scales of the fish are very thin.
The family Palaeocentrotidae can be distinguished from other families of the suborder Veliferoidei by the following characteristics:
- Hard rays are only present in the middle section of the dorsal fin.
- The first fin carrier (pterygiophore) of the dorsal fin is located in front of the first neural spine .
Genera
- Natgeosocus Bannikov, 2014, Rupelium of the Caucasus
- Palaeocentrotus Kühne, 1941, Lower Ypresium of Denmark ( Fur-Formation ), ( type species )
literature
- Bannikov, AF 2014. A new genus of the family Palaeocentrotidae (Teleostei, Lampridiformes) from the Oligocene of the northern Caucasus and comments on other fossil Veliferoidei. Paleontological Journal, 48 (6): 624-632. doi: 10.1134 / S0031030114060021