Blochius
| Blochius | ||||||||||||
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Blochius longirostris |
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| Temporal occurrence | ||||||||||||
| Eocene | ||||||||||||
| ~ 40 million years | ||||||||||||
| Locations | ||||||||||||
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| Systematics | ||||||||||||
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| Scientific name of the family | ||||||||||||
| Blochiidae | ||||||||||||
| Bleeker , 1859 | ||||||||||||
| Scientific name of the genus | ||||||||||||
| Blochius | ||||||||||||
| Volta , 1800 | ||||||||||||
Blochius is an extinct genus of fish whose fossil remains in the northern Italian Monte Bolca - Formation were found. Some rostral fragments that may haveto be assigned to Blochius come from the Congo.
features
Blochius was about 60 cm long and had a very slender elongated figure, a narrow head with elongated upper and lower jaws and large eyes. The long upper jaw is formed by the premaxillary and has longitudinal edges. It is usually longer than the lower jaw. Both jaws are set with sharp teeth. The dorsal fin stretches like a seam over the entire trunk, the likewise seam-like anal fin only begins under the middle of the body. The dorsal fin can potentially be laid down in a pit while swimming fast. The paired fins are small, the caudal fin is crescent-shaped. With the exception of the last caudal fin vertebrae , the 24 elongated vertebrae have no neural processes. The caudal fin skeleton consists of two vertebrae, an epurale, an elongated, free-standing bone, and two hypuralia . Two rows of extensively overlapping scales extend from the rear edge of the gill cover to the caudal stalk.
Way of life
Blochius was probably a predatory fish that lived in the Tethys (Monte Bolca is a length of the north coast of Tethys) in the upper 100 meters of the water column and swam and hunted with sinusoidal movements ( anguilliform swimming style ) of the body.
species
- Blochius longirostris Volta, 1796 ( type species )
- Blochius macropterus de Zigno, 1887 (only one specimen known)
- “Blochius” moorheadi Eastman, 1911 ( noun dubium )
Systematics
Until 2019 Blochius was the only genus of the Blochiidae family that is related to the recent sword and spearfish ( Xiphioidea ). In 2019, a second genus of the family was described with Loancorhynchus .
literature
- Harry L. Fierstine: Fossil History of Billfishes (Xiphioidei). Bulletin of Marine Science, Volume 79, Issue 3, January 2006, pp. 433-453 abstract .
- Karl Albert Frickhinger: Fossils Atlas Fishes. Mergus-Verlag, Melle, 1999, ISBN 3-88244-018-X .
Individual evidence
- ↑ Otero RA 2019. Loancorhynchus catrillancai gen. Et sp. nov., a new swordfish (Xiphioidei, Blochiidae) from the Middle Eocene of central Chile. PeerJ 7: e6671 doi: 10.7717 / peerj.6671