| Cyphornis Temporal range:Early Miocene (see text) | |
|---|---|
Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Aves |
| Order: | †Odontopterygiformes |
| Family: | †Pelagornithidae |
| Genus: | †Cyphornis Cope, 1894 |
| Species: | †C. magnus |
| Binomial name | |
| †Cyphornis magnus Cope, 1894 | |
| Synonyms | |
See text | |
Cyphornis is agenus of theprehistoricpseudotooth birds. These were probably rather close relatives of eitherpelicans andstorks, or ofwaterfowl, and are here placed in theorderOdontopterygiformes to account for this uncertainty.[1]
Only a singlespecies,Cyphornis magnus, is known to date. It is only known with certainty from a single specimen, the rather abradedproximal part of a lefttarsometatarsus which was found atCarmanah Point onVancouver Island (Canada), where theJuan de Fuca Strait opens into thePacific. The deposits from which it originated were initially dated to theEocene; subsequent authors have usually assigned them to theEarly Miocene though certainly rocks from around theEo-Oligocene boundary also occur in the region where it was found. At the time of its discovery, it "probably represent[ed] the largest known bird of flight."[2] Even today it is one of the largest (though not heaviest) flying birds known.[3]
Some huge pseudotooth wing bone fossils have been found inOregon. SpecimenLACM 128462, a mostly completeproximal end of a leftulna, originates from theKeasey Formation ofWashington County. LACM 127875 are fragments of the proximalhumerus ends, the proximal right ulna and the right radius of a single individual presumed to be of the same species; they were found in thePittsburg Bluff Formation nearMist. These remains all date from the Eo-Oligocene boundary, and considering their size they may well be ofC. magnus if it is in fact that old, or of its ancestor or older relative.[4]
Due to its fragmentary nature – the bones of pseudotooth bords are very thin-walled and light and notoriously easily broken and crushed whenfossilizing – it was often allied with the enigmaticCladornis, and though placed in theorderPelecaniformes (as pseudotooth birds often were) separated in asuborderCladornithes. But the slightly older (Late Oligocene)Cladornis from theArgentinian part ofPatagonia is known from adistal right tarsometatarsus only, and thus not directly comparable toCyphornis. The two genera were allied simply because of their size and because they both vaguely reminded of the tarsometatarsus of pelicans. Today however,Cladornis is more generally held to be aterrestrial bird rather than aseabird. Other authors had been more conservative all along, and consideredCyphornis quite close topelicans, uniting these as asuperfamily Pelecanides in suborder Pelecanae, or later on (after the endings oftaxonomic ranks were fixed to today's standard) Pelecanoidea in suborder Pelecani.[5]
To set it apart from its alleged relatives,Cyphornis was early on separated in afamily Cyphornithidae together withPalaeochenoides mioceanus and eventually alsoTympanonesiotes wetmorei which are also little-known pseudotooth birds but inhabited theAtlantic. But these are probably all closely related to the better-knownPelagornis,type genus of the family Pelagornithidae. And even ifCyphornis is thesenior synonym of all the later-described genera (which is not very likely), according to the rules ofzoological nomenclature the family name Pelagornithidae would not change. Thus Cyphornithidae would almost certainly be ajunior synonym of Pelagornithidae even if the pseudotooth birds are (as some have proposed) divided into several families – rather than being all placed in the Pelagornithidae as is usual nowadays –, asCyphornis,Osteodontornis,Palaeochenoides,Pelagornis and perhaps the smallerTympanoneisiotes appear to be very closely related and are probably all part of amonophyletic lineage of (usually) giant pseudotooth birds. Only if thePacific lineage is sufficiently distinct, the Cyphornithidae would remain valid, but in this case they would presumably not include the Atlantic forms.[6]
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