Argochampsa

Taxobox
name = "Argochampsa"
fossil_range = Paleocene
status=fossil


regnum = Animalia
phylum = Chordata
classis = Sauropsida
ordo = Crocodylia
superfamilia=Gavialoidea
genus = "Argochampsa"
genus_authority=Hua and Jouve, 2004
subdivision_ranks=Species
subdivision=
*"A. krebsi" Hua and Jouve, 2004 (type)

"Argochampsa" (meaning "Argo crocodile", in reference to the mythological "Argo" of Jason) is an extinct genus of gavialoid crocodilian, related to modern gharials. It lived in the Paleocene of Morocco. Described by Hua and Jouve in 2004, the type species is "A. krebsi", with the species named for the late professor B. Krebs. "Argochampsa" had a long narrow snout, and appears to have been marine in habits.cite journal |last=Hua |first=Stephane |coauthors=and Jouve, Stéphane |year=2004 |title=A primitive marine gavialoid from the Paleocene of Morocco |journal=Journal of Vertebrate Paleontology |volume=24 |issue=2 |pages=341-350 ]

"Argochampsa" is based on OCP DEK-GE 1201, a nearly complete skull from the Oulad Abdoun Basin, in the vicinity of Khouribga, Morocco. The skull, 43.3 centimeters long (17.0 in), had a long, narrow snout, marking it as a longirostrine crocodilian; the snout made up about 70% of the skull's length. The premaxillae at the tip of the snout were downturned, and the tip somewhat squared off, with the first few tooth positions in a straight line perpendicular to the long axis of the skull. There were five teeth in each premaxilla and 26 in each maxilla (the main tooth-bearing bone of the upper jaw). The nasal bones were fused, and there were several short diastemas or gaps in the tooth row at the tip of the snout. More recently, material from the lower jaw, neck and back vertebrae, the upper arm, and armor has been recovered.cite journal |last=Jouve |first=Stéphane |coauthors=Iarocheneb, Mohamed; Bouyac, Baâdi; and Amaghzaz, Mbarek |year=2006 |title=New material of "Argochampsa krebsi" (Crocodylia: Gavialoidea) from the Lower Paleocene of the Oulad Abdoun Basin (Morocco): phylogenetic implications |journal=Geobios |volume=39 |issue=6 |pages=817-832 |doi=10.1016/j.geobios.2005.07.003 ]

Hua and Jouve performed a cladistic analysis incorporating their new taxon, and found "Argochampsa" to be a gavialoid, but outside of the clade Gavialidae. They noted that the snout shape of "Argochampsa" is unusual among crocodilians, with only pholidosaurids and "Terminonaris" having similarly shaped snout tips, and suggested that this layout may have facilitated precise occlusion. "Argochampsa" lived in an environment otherwise dominated by dyrosaurid marine crocodyliforms.

References

External links

* [http://paleodb.org/cgi-bin/bridge.pl?action=checkTaxonInfo&taxon_no=96628 "Argochampsa"] in the Paleobiology Database