Xiphiorhynchus
| Xiphiorhynchus | ||||||||||||
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crushed skull fossil of Xiphiorhynchus |
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| Temporal occurrence | ||||||||||||
| Lutetium ( Eocene ) to Piacenzium ( Pliocene ) | ||||||||||||
| 47.8 to 2.588 million years | ||||||||||||
| Locations | ||||||||||||
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| Systematics | ||||||||||||
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| Scientific name of the subfamily | ||||||||||||
| Xiphiorhynchinae | ||||||||||||
| Regan , 1909 | ||||||||||||
| Scientific name of the genus | ||||||||||||
| Xiphiorhynchus | ||||||||||||
| van Beneden , 1871 | ||||||||||||
Xiphiorhynchus is an extinct but long-lived genus of fish from the swordfish family (Xiphiidae). Everythingknownabout Xiphiorhynchus is based on fragmented and poorly preserved fossils. Of the nine species described so far, six are only known by their holotype , five only by a single fragment of a rostrum and one only by a few vertebrae. Two holotypes have since been lost again ( X. homalorhamphus and X. hungaricus ). Only X. priscus is known to have a skull.
features
Xiphiorhynchus had a sword-like upper jaw rust, which was round to oval in cross-section and set on its underside with brush-shaped teeth. Inside the rostrum were two pairs of longitudinal channels, the upper pair being closer to the center line of the rostrum than the lower pair. The lower jaw is strong and the same length as or shorter than the upper jaw rust.
Way of life
Xiphiorhynchus was probably a predatory fish that inhabited the coastal regions of tropical seas. A few specimens of X. priscus and the holotype of X. kimblalocki were found in offshore deposits .
species
Nine species have been described so far . In addition, a tenth, previously undescribed species is known ( X. Cf. eocaenicus (Woodward, 1901), USA).
- X. aegypticus (Hamlet, 1929), Egypt
- X. elegans (van Beneden, 1871)
- X. eocaenicus (Woodward, 1901), England
- X. priscus (Agassiz, 1844), USA
- X. homalorhamphus (Cope, 1869)
- X. kimblalocki (Fierstine & Applegate, 1974), USA
- X. rupeliensis (Leriche, 1909), Belgium
- X. hungaricus (Hamlet, 1943), Hungary
- X. rotundus (Woodward, 1901), United States
Systematics
Xiphiorhynchus is closely related to the recent swordfish and is assigned to the monogeneric subfamily Xiphiorhynchinae within the family Xiphiidae .
literature
- Harry L. Fierstine: Fossil History of Billfishes (Xiphioidei). In: Bulletin of Marine Science. Volume 79, No. 3, January 2006, pp. 433-453 ( abstract ).