Montanazhdarcho Temporal range:
Late Cretaceous,
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Reconstructed skeletons | |
Scientific classification
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Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Order: | † Pterosauria |
Suborder: | † Pterodactyloidea |
Clade: | † Azhdarchoidea |
Genus: | †
Montanazhdarcho Padian, de Ricqlès & Horner, 1995 |
Type species | |
†Montanazhdarcho minor Padian, Ricqlès & Horner, 1995
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Montanazhdarcho is a genus of azhdarchoid pterosaur from the Late Cretaceous period ( Campanian stage) of what is now the state of Montana, United States. Montanazhdarcho is known from only one species, M. minor.
The holotype specimen, MOR 691 ( Museum of the Rockies), was found by Robert W. Harmon in Glacier County, in the territory of the Blackfoot, in sandstone of the Upper Two Medicine Formation, a layer about 74 million years old. The genus name Montanazhdarcho was first given informally in 1993 by Kevin Padian, Armand de Ricqlès, and Jack Horner. [1] It was then named formally in 1995 by the same researchers, [2] and was fully described in 2002. [3]
The type species is Montanazhdarcho minor. The generic name refers to the state of Montana and to the related species Azhdarcho. The specific name means "the smaller one" in Latin, a reference to the relatively small size in comparison to closely related forms.
Montanazhdarcho was a relatively small pterosaur, reaching 2.5 m (8.2 ft) in wingspan. [4] The fossil is largely uncompressed and that of an adult exemplar, as established by a study of the bone by de Ricqlès. It consists of a partial left wing, lacking the outer three wing finger phalanges, a complete shoulder girdle, a crushed cervical vertebra and two fragments of the symphysis of the mandible. The jaws were edentulous, i.e. they lacked teeth. [1] [2]
Montanazhdarcho was by the authors assigned to the Azhdarchidae, mainly based on the elongated form of the neck vertebra. Compared to other azhdarchids however, it was small; the fragments of humerus, radius, and carpal suggest an animal with a 2.5 m (8.2 ft) wingspan. Its ulna was longer than the wing metacarpal, which is atypical for azhdarchids. In addition to this, a phylogenetic study in 2015 has disagreed to its phylogenetic position, and reassigned Montanazhdarcho as a non-azhdarchid azhdarchoid. [5] However, in 2018, Nicholas Longrich and colleagues had recovered Montanazhdarcho within the Azhdarchidae again, though placed in the basalmost position. [4] Their phylogenetic analysis is shown below:
Montanazhdarcho Temporal range:
Late Cretaceous,
| |
---|---|
![]() | |
Reconstructed skeletons | |
Scientific classification
![]() | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Order: | † Pterosauria |
Suborder: | † Pterodactyloidea |
Clade: | † Azhdarchoidea |
Genus: | †
Montanazhdarcho Padian, de Ricqlès & Horner, 1995 |
Type species | |
†Montanazhdarcho minor Padian, Ricqlès & Horner, 1995
|
Montanazhdarcho is a genus of azhdarchoid pterosaur from the Late Cretaceous period ( Campanian stage) of what is now the state of Montana, United States. Montanazhdarcho is known from only one species, M. minor.
The holotype specimen, MOR 691 ( Museum of the Rockies), was found by Robert W. Harmon in Glacier County, in the territory of the Blackfoot, in sandstone of the Upper Two Medicine Formation, a layer about 74 million years old. The genus name Montanazhdarcho was first given informally in 1993 by Kevin Padian, Armand de Ricqlès, and Jack Horner. [1] It was then named formally in 1995 by the same researchers, [2] and was fully described in 2002. [3]
The type species is Montanazhdarcho minor. The generic name refers to the state of Montana and to the related species Azhdarcho. The specific name means "the smaller one" in Latin, a reference to the relatively small size in comparison to closely related forms.
Montanazhdarcho was a relatively small pterosaur, reaching 2.5 m (8.2 ft) in wingspan. [4] The fossil is largely uncompressed and that of an adult exemplar, as established by a study of the bone by de Ricqlès. It consists of a partial left wing, lacking the outer three wing finger phalanges, a complete shoulder girdle, a crushed cervical vertebra and two fragments of the symphysis of the mandible. The jaws were edentulous, i.e. they lacked teeth. [1] [2]
Montanazhdarcho was by the authors assigned to the Azhdarchidae, mainly based on the elongated form of the neck vertebra. Compared to other azhdarchids however, it was small; the fragments of humerus, radius, and carpal suggest an animal with a 2.5 m (8.2 ft) wingspan. Its ulna was longer than the wing metacarpal, which is atypical for azhdarchids. In addition to this, a phylogenetic study in 2015 has disagreed to its phylogenetic position, and reassigned Montanazhdarcho as a non-azhdarchid azhdarchoid. [5] However, in 2018, Nicholas Longrich and colleagues had recovered Montanazhdarcho within the Azhdarchidae again, though placed in the basalmost position. [4] Their phylogenetic analysis is shown below: