Istiodactylids Temporal range: Early Cretaceous, Possible Middle Jurassic record | |
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Life restoration of Istiodactylus latidens feeding on a stegosaur corpse. | |
Scientific classification ![]() | |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Reptilia |
Order: | † Pterosauria |
Suborder: | † Pterodactyloidea |
Clade: | † Pteranodontoidea |
Clade: | † Lanceodontia |
Clade: | † Istiodactyliformes |
Family: | † Istiodactylidae Howse, Milner & Martill, 2001 |
Type species | |
† Ornithodesmus latidens Seeley, 1901 | |
Genera | |
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Istiodactylidae is a small family of pterosaurs. This family was named in 2001 after the type genus Istiodactylus was discovered not to be a member of the genus Ornithodesmus .
Remains of taxa that can be confidently assigned to Istiodactylidae have been found in the UK and China, in rocks dating from the Early Cretaceous period (Barremian to Aptian stage). [2] Arbour and Currie (2011) described Canadian Gwawinapterus beardi as a member of Istiodactylidae living in the late Cretaceous (upper Campanian stage); [3] however, Witton (2012) suggested the tooth replacement pattern in this animal does not match that of pterosaurs, suggesting that the species might be non-pterosaurian. [2] Additional research suggested that the species was in fact a fish. [4] The earliest known species might be Archaeoistiodactylus linglongtaensis , from the Middle Jurassic of China; [5] however, it also has been suggested that the holotype specimen of this species might actually be a poorly preserved specimen of Darwinopterus . [6] Hongshanopterus , a supposed istiodactylid from China, has been reclassified as a non-istiodactylid member of Ornithocheiroidea of uncertain phylogenetic placement by Witton (2012). [2]
Istiodactylids were medium-sized pterosaurs with flat, rounded jaws similar to that of a duck. They had small teeth lining their jaws, however, and this can mostly be seen in the more advanced genera such as Istiodactylus . [7]
Below is a cladogram showing the phylogenetic placement of this group within Pteranodontia from Andres and Myers (2013). [8]
Pteranodontia |
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The cladogram below is a topology recovered by Kellner et al. (2019). In the analyses, they recovered Istiodactylidae within the more inclusive group Istiodactyliformes, and assigned both Istiodactylus and Liaoxipterus to a new subfamily called Istiodactylinae, but kept Nurhachius as a basal member. [9]
Istiodactyliformes |
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Unlike most ornithocheiroids, istiodactylids bear morphologies suited to a terrestrial life and many of their fossils have been found in freshwater-deposits. Istiodactylids are considered to be pterosaurian equivalents to vultures: acting as the clean-up crew in their habitats. The swimming abilities of Istiodactylids have not been analyzed, in contrast to Ornithocheirids.[ citation needed ]