''Dawndraco'' is a controversial

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial n ...

pteranodontid The Pteranodontidae are a family of large pterosaurs of the Cretaceous Period of North America and Africa. The family was named in 1876 by Othniel Charles Marsh. Pteranodontids had a distinctive, elongated crest jutting from the rear of the h ...

pterosaur Pterosaurs (; from Greek ''pteron'' and ''sauros'', meaning "wing lizard") is an extinct clade of flying reptiles in the Order (biology), order, Pterosauria. They existed during most of the Mesozoic: from the Late Triassic to the end of the Cre ...

from the

Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', ...

of North America. It is likely synonymous with the contemporary pteranodontid ''

Geosternbergia ''Geosternbergia'' is an extinct genus of pteranodontid pterodactyloid pterosaur from the Late Cretaceous geological period of North America. ''Geosternbergia'' was one of the largest pterosaur genera, and had a wingspan of up to . Discover ...

.'' ''Dawndraco'' was named by Alexander W.A. Kellner in

2010 File:2010 Events Collage New.png, From top left, clockwise: The 2010 Chile earthquake was one of the strongest recorded in history; The Eruption of Eyjafjallajökull in Iceland disrupts air travel in Europe; A scene from the opening ceremony of ...

. The

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen( ...

is ''Dawndraco kanzai''. The generic name combines the Dawn deity of the

Iroquois The Iroquois ( or ), officially the Haudenosaunee ( meaning "people of the longhouse"), are an Iroquoian-speaking confederacy of First Nations peoples in northeast North America/ Turtle Island. They were known during the colonial years to ...

with a

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power ...

''draco'', "dragon". The

specific name Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany), the two-part (bino ...

refers to the Kanza tribe of

Kansas Kansas () is a state in the Midwestern United States. Its capital is Topeka, and its largest city is Wichita. Kansas is a landlocked state bordered by Nebraska to the north; Missouri to the east; Oklahoma to the south; and Colorado to ...

. ''Dawndraco'' is based on the

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of seve ...

specimen UALVP 24238, a partial

skeleton A skeleton is the structural frame that supports the body of an animal. There are several types of skeletons, including the exoskeleton, which is the stable outer shell of an organism, the endoskeleton, which forms the support structure inside ...

including an almost complete

skull The skull is a bone protective cavity for the brain. The skull is composed of four types of bone i.e., cranial bones, facial bones, ear ossicles and hyoid bone. However two parts are more prominent: the cranium and the mandible. In humans, t ...

and lower jaws. It was recovered in 1974 by Richard C. Fox and Allen Lindoe from rocks of the lower part of the

Smoky Hill Chalk Member The Smoky Hill Chalk Member of the Niobrara Chalk formation is a Cretaceous conservation Lagerstätte, or fossil rich geological formation, known primarily for its exceptionally well-preserved marine reptiles. Named for the Smoky Hill River, the S ...

of the

Niobrara Formation The Niobrara Formation , also called the Niobrara Chalk, is a geologic formation in North America that was deposited between 87 and 82 million years ago during the Coniacian, Santonian, and Campanian stages of the Late Cretaceous. It is compose ...

Utica, Kansas Utica is a city in Ness County, Kansas, United States. As of the 2020 census, the population of the city was 99. History The first post office in Utica was established in 1879. Utica was named by early pioneer C.W. Bell who was from Utica, N ...

. These rocks date to the late

Coniacian The Coniacian is an age or stage in the geologic timescale. It is a subdivision of the Late Cretaceous Epoch or Upper Cretaceous Series and spans the time between 89.8 ± 1 Ma and 86.3 ± 0.7 Ma (million years ago). The Coniacian is preceded b ...

or early

Santonian The Santonian is an age in the geologic timescale or a chronostratigraphic stage. It is a subdivision of the Late Cretaceous Epoch or Upper Cretaceous Series. It spans the time between 86.3 ± 0.7 mya (million years ago) and 83.6 ± 0.7 mya. ...

stage, about 86 million years ago. The specimen was earlier referred to ''

Pteranodon ''Pteranodon'' (); from Ancient Greek (''pteron'', "wing") and (''anodon'', "toothless") is a genus of pterosaur that included some of the largest known flying reptiles, with ''P. longiceps'' having a wingspan of . They lived during the late C ...

sternbergi''. However, when Kellner in 2010 assigned this latter species to the genus ''

'', he concluded that specimen UALVP 24238 was too different from it to be accounted for by individual variation or

sexual dimorphism Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most an ...

and therefore named a separate genus. A unique trait is that the snout does not strongly taper anteriorly as with ''Pteranodon'', the upper and lower margins running almost parallel instead. Kellner further argued that the provenance of the specimen - from rock units between those of other ''Pteranodon'' holotypes - supported his interpretation of morphological differences as being taxonomic in nature, rather than relating to growth or gender. '''Dawndraco was assigned by Kellner to the Pteranodontidae. In a detailed description and discussion of UALVP 24238, Martin-Silverstone ''et al.'' (2017) concluded that '''D. kanzai''' was not a distinct genus or species from ''Pteranodon.'' They showed that its taxonomic characterisations were suspect or erroneous, and that stratigraphic arguments used to further distinguish '''D. kanzai from other pteranodontids were questionable when compared to the geologic ranges of other Smoky Hill Chalk species. They concluded that UALVP 24238 is better interpreted as a small (not fully osteologically mature) individual of the larger size-class (male) of '' Pteranodon sternbergi''. Their interpretation echoes sceptism expressed about the 2010 ''Pteranodon'' revision from other palaeontologists, several of whom have continued to use pre-2010 taxonomies when discussing the Smoky Hill Chalk pteranodonts. In 2014, Andres, Clark, and Xu stated that they would continue to follow the pre-2010 taxonomy of pteranodontids, and referred the new species named by Kellner, including ''Dawndraco'', back to their original classifications following Bennett.

References

{{Portal bar, Paleontology, Cretaceous, United States Late Cretaceous pterosaurs of North America Pteranodontians Fossil taxa described in 2010 Taxa named by Alexander Kellner

See also

References