View source for Nyctosaurus

{{short description|Genus of nyctosaurid pterosaur from the Late Cretaceous}}
{{Use mdy dates|date=January 2021}}
{{Automatic taxobox
|fossil_range = {{fossilrange|Santonian|Campanian|refs=<ref>{{cite book |last1=Hone|first1=David|last2=Witton|first2=Mark|last3=Martill|first3=David|page=213|title=New Perspectives on Pterosaur Paleobiology |year=2018 |publisher=The Geological Society |location=London |isbn=978-1-78620-317-5 |language=en}}</ref>}}
|image = Dinosaurs at CMNH 49.JPG
|image_upright = 1.15
|image_caption = Fossil specimen (CM 11422) of ''Nyctosaurus gracilis'' in the [[Carnegie Museum of Natural History]]
|taxon = Nyctosaurus
|authority = [[Othniel Charles Marsh|Marsh]], 1876
|type_species = {{extinct}}'''''Nyctosaurus gracilis'''''
|type_species_authority = Marsh, 1876
|subdivision_ranks = Species
|subdivision =
*{{extinct}}'''''N. gracilis''''' <br/><small>(Marsh, 1876)</small>
*{{extinct}}'''''N. nanus''''' <br/><small>(Marsh, 1881)</small>
*{{extinct}}'''''"N." lamegoi''''' <br/><small>Price, 1953</small>
|synonyms =
{{collapsible list|bullets = true
|title=<small>Genus synonymy</small>
|''[[Pteranodon]] (Nyctosaurus)'' <br/><small>(Marsh, 1876)</small>
|''Nyctodactylus'' <br/><small>Marsh, 1881</small>
}}
{{collapsible list|bullets = true
|title=<small>Synonyms of ''N. gracilis''</small>
|''Pteranodon gracilis'' <br/><small>Marsh, 1876</small>
|''Pteranodon (Nyctosaurus) gracilis'' <br/><small>(Marsh, 1876)</small>
|''Nyctodactylus gracilis'' <br/><small>(Marsh, 1876)</small>
|''Nyctosaurus leptodactylus'' <br/><small>[[Samuel Wendell Williston|Williston]], 1903</small>
|''Pteranodon bonneri'' <br/><small>Miller, 1972</small>
|''Pteranodon (Nyctosaurus) bonneri'' <br/><small>(Miller, 1972)</small>
|''Nyctosaurus bonneri''<br /><small>(Miller, 1972)</small>
}}
{{collapsible list|bullets = true
|title=<small>Synonyms of ''N. nanus''</small>
|''Pteranodon nanus'' <br/><small>Marsh, 1881</small>
}}
}}
'''''Nyctosaurus''''' (meaning "night lizard") is a [[genus]] of [[nyctosaurid]] [[pterosaur]] from the [[Late Cretaceous]] period of what is now the [[Niobrara Formation]] of the mid-western [[United States]], which, during the time ''Nyctosaurus'' was alive, was covered in an extensive shallow sea. Some remains belonging to a possible ''Nyctosaurus'' species called ''"N." lamegoi'' have been found in [[Brazil]], though it likely belongs to a different genus ''[[Simurghia]]''. The genus ''Nyctosaurus'' has had numerous species referred to it, though how many of these may actually be valid requires further study. At least one species possessed an extraordinarily large antler-like [[cranial crest]].<ref name=benett2003/>
''Nyctosaurus'' was a mid-sized pterosaur that lived along the shores of the Niobrara Formation of the United States, which back then was within a large inland sea called the [[Western Interior Seaway]]. It has been suggested that it would have flown similar to modern-day [[soaring birds]] such as [[albatross]]es, which consisted of flying very long distances and rarely flapping.<ref name="xingetal2009"/> The species ''N. gracilis'' and ''N. nanus'' have previously been considered as species of the closely related ''[[Pteranodon]]'', back then known as ''P. gracilis'' and ''P. nanus'', due to their similarities.
==Discovery and species==
[[File:Fossil pterosaur.jpg|thumb|left|Juvenile ''N. gracilis'' specimen at the [[Field Museum]], Williston's IL P. 25026]]
The first ''Nyctosaurus'' fossils were described in 1876 by [[Othniel Charles Marsh]], based on fragmentary material, [[holotype]] YPM 1178, from the [[Smoky Hill River]] site in [[Kansas]]. Marsh referred the specimen to a species of his new genus ''Pteranodon'', as ''Pteranodon gracilis''.<ref name=marsh1876a>Marsh, O.C. (1876a). "Notice of a new sub-order of Pterosauria." ''American Journal of Science'', '''11'''(3): 507–509.</ref> Later that year, Marsh reclassified the species in its own genus, which he named ''Nyctosaurus'', derived from the Greek νύξ  (nyx, "night") and σαῦρος (sauros, "lizard").<ref name=marsh1876b>Marsh, O.C. (1876b). "Principal characters of American pterodactyls." ''American Journal of Science'', '''12''': 479–480.</ref> In 1881, Marsh incorrectly assumed the name was preoccupied and changed it into ''Nyctodactylus'', which thus is now a [[junior synonym]].<ref name=marsh1881>Marsh, O.C. (1881). "Note on American pterodactyls." ''American Journal of Science'', '''21''': 342–343.</ref> In 1902, [[Samuel Wendell Williston]] described the most complete skeleton then known (P 25026) discovered in 1901 by H. T. Martin. In 1903, Williston named a second species, ''N. leptodactylus'', but this is today considered identical to ''N. gracilis''.
[[File:Nyctosaurus gracilis skull - Pterosaurs Flight in the Age of Dinosaurs.jpg|thumb|Cast of the skull with an elongated crest]]
In 1953, Brazilian paleontologist [[Llewellyn Ivor Price]] named a partial [[humerus]], DGM 238-R found in [[Brazil]], ''N. lamegoi''; the specific name honours the [[geologist]] [[Alberto Ribeiro Lamego]]. This species has an estimated wingspan of four metres; today, it is generally considered to be a form different from ''Nyctosaurus'', but has not yet been assigned its own genus name.<ref name=benett2003/><ref name=liprice1953>{{cite journal|last=Price|first=Llewellyn Ivor|title=A presença de Pterosauria no Cretáceo Superior do Estado da Paraíba|journal=Notas Preliminares e Estudos, Divisão de Geologia e Mineralogia, Brasil|year=1953|issue=71|pages=1–10}}</ref><ref name=kellner1989>{{cite journal|last=Kellner|first=Alexander Wilhelm Armin|title=Os répteis voadores do cretáceo brasileiro|journal=Anuário do Instituto de Geociências|year=1989|volume=12|pages=86–106|doi=10.11137/1989_0_86-106 |doi-access=free}}</ref> This species is possibly from the [[Campanian]]-[[Maastrichtian]] age strata and might represent a species of ''[[Simurghia]]''.<ref name="Longrich2018"/><ref name=Pegas2024/>
In 1972, a new skeleton, FHSM VP-2148, in 1962 discovered by [[George Fryer Sternberg]], was named ''N. bonneri''; today, it is generally seen as identical to ''N. gracilis''.<ref name=benett2003/><ref name="Longrich2018"/><ref>Eberhard Frey, Ross A. Elgin, Wolfgang Stinnesbeck, José Manuel Padilla-Gutiérrez, Christina Ifrim, Samuel Giersch, and Arturo H. González-González, 2012, [http://www.scielo.org.mx/scielo.php?script=sci_arttext&pid=S1026-87742012000100009 "A new specimen of nyctosaurid pterosaur, cf. ''Muzquizopteryx'' sp. from the Late Cretaceous of northeast Mexico."] ''[[Revista Mexicana de Ciencias Geológicas]]'' '''29'''(1): 131–139</ref>
In 1978, Gregory Brown prepared the most complete ''Nyctosaurus'' skeleton currently known, UNSM 93000.<ref>Brown GW (1978) Preliminary report on an articulated specimen of ''Pteranodon (Nyctosaurus'') ''gracilis''. Proceedings of the Nebraska Academy of Science 88: 39.</ref>
In 1984, [[Robert Milton Schoch]] renamed ''Pteranodon nanus'' (Marsh 1881), "the dwarf", ''Nyctosaurus nanus''.<ref name=marsh1881/> The question of this species validity is currently pending further study.<ref name=benett2003>{{cite journal|author=Bennett, S.C.|year=2003|title=New crested specimens of the Late Cretaceous pterosaur ''Nyctosaurus''.|journal=Paläontologische Zeitschrift|volume=77|pages=61–75|doi=10.1007/BF03004560|bibcode=2003PalZ...77...61B |s2cid=129438441|url=https://link.springer.com/article/10.1007/BF03004560}}.</ref>
In the early 2000s, Kenneth Jenkins of [[Ellis, Kansas]] collected two specimens of ''Nyctosaurus'', which were the first to demonstrate conclusively that not only was this species crested, but that the crest in mature specimens was very large and elaborate. The specimens were purchased by a private collector in [[Austin, Texas|Austin]], [[Texas]]. Despite being in private hands rather than a museum collection, paleontologist Chris Bennett was able to study the specimens and gave them the manuscript reference numbers KJ1 and KJ2 (for Kenneth Jenkins). Bennett published a description of the specimens in 2003. Despite the unusual crests, the specimens were otherwise indistinguishable from other specimens of ''Nyctosaurus''. However, the then-currently named species were extremely similar and Bennett declined to refer them to a specific one pending further study of the differences, or lack thereof, between species of ''Nyctosaurus''.<ref name=benett2003/>
==Description==
===Size and weight===
[[File:Nyctosaurus scale mmartyniuk.png|thumb|Size of a mature, crested specimen (green) compared with a human]]
''Nyctosaurus'' was similar in anatomy to its close relative and contemporary, ''[[Pteranodon]]''. It had relatively long wings, similar in shape to modern seabirds. However, it was much smaller overall than ''Pteranodon'', with an adult wingspan of little over {{convert|2|m|ft|sp=us}}.<ref name=benett2003/> Some wingspan estimates by German paleontologist [[Peter Wellnhofer]] in 1991 however, reached a total of about {{convert|2.9|m|ft|sp=us}}, and the dubious species ''"N." lamegoi'' had a wingspan estimate of around {{convert|4|m|ft|sp=us}} according to Price back in 1953.{{sfn|Witton|2013|p=177}} It is estimated that ''N. gracillis'' had about {{convert|37.6|cm|ft|sp=us}} body length, {{convert|2.72|m|ft|sp=us}} wingspan and {{convert|1.86|kg|lb}} weight.<ref name=posture>Chatterjee, S. and Templin, R.J. (2004). ''Posture, Locomotion, and Paleoecology of Pterosaurs''. Geological Society of America, 64 pp. {{ISBN|0-8137-2376-0}}, {{ISBN|978-0-8137-2376-1}}</ref>
===Skull and beak===
Some skull specimens preserve a distinctively large crest, at least {{convert|55|cm|ft|sp=us}} tall in the older  adults, and was relatively gigantic compared to the rest of the body, while also being over three times the length of the head. The crest is composed of two long, grooved spars, one pointed upward and the other backward, arising from a common base projecting up and back from the back of the skull. The two spars were nearly equal in length, and both were nearly as long or longer than the total length of the body. The upward-pointing crest spar was at least {{convert|42|cm|ft|sp=us}} long and the backward-pointing spar was at least {{convert|32|cm|ft|sp=us}} long.<ref name=benett2003/>
The jaws of ''Nyctosaurus'' were long and extremely pointed. The jaw tips were thin and needle sharp, and are often broken off in fossil specimens, giving the appearance that one jaw is longer than the other, though in life they were probably equal in length.<ref name=benett2003/>
===Wings===
[[File:The Osteology of the Reptiles p299 Fig-190.png|thumb|Diagram of the skeleton of ''Nyctosaurus'' depicted without a crest]]
''Nyctosaurus'' had wings very similar in built to those of its relative ''Pteranodon'', which have a high [[aspect ratio (aeronautics)|aspect ratio]] and low [[wing loading]]s. The wing structure generally resembles that of the modern-day albatross, and therefore also flew like it. Unlike the related ''Pteranodon'' however, ''Nyctosaurus'' was much smaller in size, and had a relatively shorter wingspan, though still large compared to earlier pterosaurs.{{sfn|Witton|2013|p=177}}<ref name=benett2003/>
===Forelimbs===
Like the closely related ''Pteranodon'', ''Nyctosaurus'' also had relatively long forelimbs compared to other earlier genera. Most of the tendons of the upper arm and forearm were mineralized within, this is a unique feature only seen in nyctosaurids, another of which was the related ''[[Muzquizopteryx]]''. Another distinctive feature seen in ''Nyctosaurus'' was that it only had three [[phalanges]] instead of four, as seen in other [[pterodactyloid]]s, this trait is rarely seen in other pterosaurs, and perhaps may have been an [[autapomorphy]] only found in ''Nyctosaurus''.{{sfn|Witton|2013|p=179}}
''Nyctosaurus'' had unusually elongated [[metacarpal]]s which measured about 2.5 times the length of its [[humerus]]. Proportions such as these can only be seen in two other groups of pterosaurs: the [[pteranodontids]] and the [[azhdarchids]]. Another feature that ''Nyctosaurus'' had in common with ''Pteranodon'' was its wing fingers, which occupied about 55 percent of the whole wing.{{sfn|Witton|2013|p=179}}
Studies on ''Nyctosaurus'' anatomy have concluded that the first, second and third metacarpals have lost contact with the [[carpus]], similar to pteranodontids, but unlike them, ''Nyctosaurus'', and possibly other nyctosaurids, had also lost the corresponding digits except the "flight" digit.{{sfn|Witton|2013|p=179}} As a result, it was likely to have impaired its movement on the ground, leading scientists to conjecture that it spent almost all of its time on the wing and rarely landed. In particular, the lack of claws with which to grip surfaces would have made climbing or clinging to cliffs and tree trunks impossible for ''Nyctosaurus''.<ref name=benett2003/>
===Hindlimbs===
Contrary to its elongated forelimbs, ''Nyctosaurus'' had proportionally short hindlimbs compared to the overall body size. Analyses show that ''Nyctosaurus'' had the shortest hindlimbs of any pterosaur genera, in terms of hindlimb-to-body ratio, at only around 16 percent the size of its wing.{{sfn|Witton|2013|p=179}}
==Classification==
[[File:Nyctosaurus mmartyniuk.jpg|thumb|upright|Drawing of ''Nyctosaurus'' in a quadrupedal walking position]]
Below is a [[cladogram]] following Brian Andres and Timothy Myers in 2013, showing the phylogenetic placement of this genus within the clade [[Pteranodontia]]. Two species of ''Nyctosaurus'' (''N. gracilis'' and ''"N." lamegoi'') were included in the analysis, and were placed within the family [[Nyctosauridae]], sister taxa to ''Muzquizopteryx''.<ref name=LoneStarPterosaurs>{{Cite journal | last1 = Andres | first1 = B. | last2 = Myers | first2 = T. S. | doi = 10.1017/S1755691013000303 | title = Lone Star Pterosaurs | journal = Earth and Environmental Science Transactions of the Royal Society of Edinburgh | pages = 383–398 | year = 2013 | volume = 103 | issue = 3–4 | s2cid = 84617119 }}</ref>
{{clade| style=font-size:85%;line-height:85%
|label1=&nbsp;[[Pteranodontia]]&nbsp;
|1={{clade
|label1=&nbsp;[[Nyctosauridae]]&nbsp;
|1={{clade
|1=''[[Muzquizopteryx coahuilensis]]''
|2='''''"Nyctosaurus" lamegoi'''''
|3='''''Nyctosaurus gracilis'''''}}
|2={{clade
|1=''[[Alamodactylus byrdi]]''
|label2=&nbsp;[[Pteranodontoidea]]&nbsp;
|2={{clade
|1={{clade
|1=''[[Pteranodon longiceps]]''
|2=''[[Pteranodon sternbergi]]''}}
|2={{clade
|label1=&nbsp;[[Istiodactylidae]]&nbsp;
|1={{clade
|1=''[[Longchengpterus zhaoi]]''
|2={{clade
|1=''[[Nurhachius ignaciobritoi]]''
|2={{clade
|1=''[[Liaoxipterus brachyognathus]]''
|2={{clade
|1=''[[Istiodactylus latidens]]''
|2=''[[Istiodactylus sinensis]]''}} }} }} }}
|2={{clade
|1=''[[Lonchodectes compressirostris]]''
|2={{clade
|1=''[[Aetodactylus halli]]''
|2={{clade
|1=''[[Cearadactylus atrox]]''
|2={{clade
|1=''[[Brasileodactylus araripensis]]''
|2={{clade
|1=''[[Ludodactylus sibbicki]]''
|2=[[Ornithocheirae]]
}} }} }} }} }} }} }} }} }} }}
In 2018, a topology by Nicholas Longrich and colleagues had made the clade [[Pteranodontoidea]] the more inclusive group, while Pteranodontia was restricted to only pteranodontids and nyctosaurids. In this analysis, three species of ''Nyctosaurus'' were included: ''"N." lamegoi'', ''N. nanus'' and ''N. gracilis''; all three of which were placed as derived members of the Nyctosauridae.<ref name=kryptodrakon>{{Cite journal | doi = 10.1016/j.cub.2014.03.030| title = The Earliest Pterodactyloid and the Origin of the Group| journal = Current Biology| year = 2014| last1 = Andres | first1 = B. | last2 = Clark | first2 = J. | last3 = Xu | first3 = X. | pmid=24768054 | volume=24 | issue = 9| pages=1011–6| doi-access = free | bibcode = 2014CBio...24.1011A}}</ref><ref name="Longrich2018">{{cite journal|last1=Longrich|first1=Nicholas R.|last2=Martill|first2=David M.|last3=Andres|first3=Brian|last4=Penny|first4=David|title=Late Maastrichtian pterosaurs from North Africa and mass extinction of Pterosauria at the Cretaceous-Paleogene boundary|journal=PLOS Biology|date=2018|volume=16|issue=3|pages=e2001663|doi=10.1371/journal.pbio.2001663|pmid=29534059|pmc=5849296 |doi-access=free }}</ref>
{{clade| style=font-size:90%;line-height:85%
|label1=&nbsp;[[Pteranodontoidea]]&nbsp;
|1={{clade
|1=[[Ornithocheiromorpha]]
|label2=&nbsp;[[Pteranodontia]]&nbsp;
|2={{clade
|1={{clade
|label1=[[Pteranodontidae]]
|1={{clade
|1={{clade
|1=''[[Pteranodon sternbergi]]''
|2=''[[Pteranodon longiceps]]'' }}
|2=''[[Tethydraco regalis]]'' }} }}
|label2=[[Nyctosauridae]]
|2={{clade
|1=''[[Alamodactylus byrdi]]''
|2=''[[Volgadraco bogolubovi]]''
|3={{clade
|1=''[[Cretornis hlavaci]]''
|2={{clade
|1={{clade
|1=''[[Alcione elainus]]''
|2=''[[Simurghia robusta]]'' }}
|2={{clade
|1=''[[Muzquizopteryx coahuilensis]]''
|2={{clade
|1={{clade
|1=''[[Barbaridactylus grandis]]''
|2='''''Nyctosaurus lamegoi''''' }}
|2={{clade
|1='''''Nyctosaurus nanus'''''
|2='''''Nyctosaurus gracilis'''''
}} }} }} }} }} }} }} }} }}
In 2024, ''"N." lamegoi'' was included as a species of ''[[Simurghia]]'' based on phylogenetic analysis.<ref name=Pegas2024>{{Cite journal |last1=Pêgas |first1=Rodrigo V. |date=2024-06-10 |title=A taxonomic note on the tapejarid pterosaurs from the Pterosaur Graveyard site (Caiuá Group, ?Early Cretaceous of Southern Brazil): evidence for the presence of two species |journal=[[Historical Biology]] |language=en |pages=1–22 |url=https://www.researchgate.net/publication/381306918 |doi=10.1080/08912963.2024.2355664 |issn=0891-2963}}</ref>
==Paleobiology==
===Life history===
[[File:Nyctosaurus DB.jpg|thumb|upright|Artist's impression of a crested specimen]]
''Nyctosaurus'', like its relative ''Pteranodon'', appears to have grown very rapidly after hatching. Fully adult specimens are no larger than some immature specimens such as P 25026 (pictured below), indicating that ''Nyctosaurus'' went from hatching to adult size (with wingspans of {{convert|2|m|ft|sp=us}} or more) in under a year. Some sub-adult specimens have been preserved with their skulls in nearly pristine condition, and lack any trace of a head crest, indicating that the distinctively large crest only began to develop after the first year of life. The crest may have continued to grow more elaborate as the animal aged, though no studies have examined the age of the fully adult, large-crested specimens. These individuals may have been 5 or even 10 years old at the time of their deaths.<ref name=benett2003/>
===Crest function===
[[File:Nyctosaurus.png|thumb|left|upright|Skeletal reconstruction of a crested specimen]]
Only five relatively complete ''Nyctosaurus'' skulls have been found. Of those, one is juvenile and does not possess a crest (specimen FMNH P 25026), and two are more mature and may show signs of having had a crest but are too badly crushed to say for sure (FHSM 2148 and CM 11422). Two specimens (KJ1 and KJ2) described in 2003, however, preserved an enormous double-pronged crest.<ref name=benett2003/>
A few scientists had initially hypothesized that this crest, which resembles an enormous [[antler]], may have supported a skin "headsail" used for stability in flight. While there is no fossil evidence for such a sail, studies have shown that a membranous attachment to the bony crest would have imparted aerodynamic advantages.<ref name="xingetal2009">{{cite journal|author=Xing, L. |author2=Wu, J. |author3=Lu, Y. |author4=Lu, J. |author5=Ji, Q. |year=2009|title=Aerodynamic characteristics of the crest with membrane attachment on Cretaceous pterodactyloid ''Nyctosaurus''.|journal=Acta Geologica Sinica|volume=83|issue=1|pages=25–32|doi=10.1111/j.1755-6724.2009.00003.x|bibcode=2009AcGlS..83...25X |s2cid=129700882 |url=https://www.researchgate.net/publication/229502318}}</ref> However, in the actual description of the fossils, paleontologist Christopher Bennett argued against the possibility of a membrane or soft tissue extension to the crest. Bennett noted that the edges of each prong were smooth and rounded, and showed no evidence for any soft-tissue attachment points. He also compared ''Nyctosaurus'' with large-crested [[tapejarids]], which do preserve soft tissue extensions supported by prongs, and showed that, in those species, the attachment points were obvious, with jagged edges where the transition from bone to soft tissue occurred. Bennett concluded that the crest was most likely used solely for display, citing similar structures in modern animals.<ref name=benett2003/> The 2009 study by Xing and colleagues testing the aerodynamics of the giant crest with a "headsail" also tested the aerodynamics of the same crest with no sail, and found that it added no significant negative factors, so a crest with no headsail would not have hindered normal flight.<ref name="xingetal2009"/> It is more likely that the crest acted mainly for display, and that any aerodynamic effects it may have had were secondary. Bennett also argued that the crest was probably not a sexually dimorphic character, as in most crested pterosaurs, including the related ''Pteranodon'', both sexes are crested and it is only the size and shape of the crest that differs. The apparently non-crested ''Nyctosaurus'' specimens therefore probably came from sub-adults.<ref name=benett2003/>
===Wing loading and speed===
Researchers [[Sankar Chatterjee]] and R.J. Templin used estimates based on complete ''Nyctosaurus'' specimens to determine weight and total wing area, and to calculate its total wing loading. They also estimated its total available flight power based on estimated musculature. Using these calculations, they estimated the cruising speed of ''Nyctosaurus gracilis'' as 9.6 meters/second (34.5 kilometers/hour or 21.4 miles/hour).<ref name=posture/>
==Paleoecology==
[[File:Cretaceous seaway.png|thumb|Map of [[North America]] during the mid-[[Cretaceous]] period, illustrating the [[Western Interior Seaway]] (middle to upper left) and other nearby seaways]]
All known ''Nyctosaurus'' fossils come from the Smoky Hill Chalk of [[Kansas]], part of the [[Niobrara Formation]]. Specifically, they are found only within a narrow zone characterized by the abundance of [[ammonite]] fossils belonging to the species ''[[Spinaptychus sternbergi]]''. These limestone deposits were laid down during a [[marine regression]] of the [[Western Interior Seaway]] that lasted between 85 and 84.5 million years ago. Therefore, ''Nyctosaurus'' was a relatively short-lived species, unlike its relative ''Pteranodon'', which is found throughout almost all of the Niobrara layers into the overlying [[Pierre Shale Formation]], and existed between 88 and 80.5 million years ago.<ref name=carpenter2003>Carpenter, K. (2003). "Vertebrate Biostratigraphy of the Smoky Hill Chalk (Niobrara Formation) and the Sharon Springs Member (Pierre Shale)." ''High-Resolution Approaches in Stratigraphic Paleontology'', '''21''': 421–437. {{doi|10.1007/978-1-4020-9053-0}}</ref>
The ecosystem preserved in this zone was unique in its abundance of vertebrate life. ''Nyctosaurus'' shared the sky with the bird ''[[Ichthyornis]]'' and with ''Pteranodon longiceps'', though the second Niobrara ''Pteranodon'' species, ''P. sternbergi'', had disappeared from the fossil record by this point. In the waters of the [[Western Interior Seaway]] below swam [[mosasaur]]s such as ''[[Clidastes]]'', ''[[Ectenosaurus]]'', ''[[Eonatator]]'', ''[[Halisaurus]]'', ''[[Platecarpus]]'' and ''[[Tylosaurus]]'', several remains of the [[plesiosaur]]s ''[[Dolichorhynchops]]'' and ''[[Polycotylus]]'', [[cephalopod]]s like ''[[Baculites]]'' and ''[[Tusoteuthis]]'', and the sea turtles such as ''[[Ctenochelys]]'' and ''[[Toxochelys]]'' were also found. Flightless diving birds such as ''[[Parahesperornis]]'' were also known from the fossil site, and a wide variety of fish including swordfish-like ''[[Protosphyraena]]'', as well as the predatory fishes ''[[Pachyrhizodus]]'', ''[[Xiphactinus]]'', ''[[Ichthyodectes]]'', ''[[Gillicus]]'', ''[[Leptecodon]]'', ''[[Enchodus]]'' and ''[[Cimolichthys]]'', the [[filter feeding]] ''[[Bonnerichthys]]'', the [[dorsal fin]]ned ''[[Bananogmius]]'', and the [[cartilaginous fish]]es ''[[Cretolamna]]'', ''[[Ptychodus]]'', ''[[Rhinobatos]]'' and ''[[Squalicorax]]'' were also found within the formation.<ref name=carpenter2003/> Several [[dinosaur]] genera were found along with ''Nyctosaurus'' remains, these included the [[nodosaurid]]s ''[[Hierosaurus]]'' and ''[[Niobrarasaurus]]'', as well as the [[hadrosaur]] ''[[Claosaurus]]''.<ref>K. Carpenter, D. W. Dilkes, and D. B. Weishampel. 1995. The dinosaurs of the Niobrara Chalk Formation (Upper Cretaceous, Kansas). Journal of Vertebrate Paleontology 15(2):275–297</ref>
==See also==
* [[List of pterosaur genera]]
* [[Timeline of pterosaur research]]
==References==
{{Reflist}}
==Further reading==
*{{cite book|last=Witton|first=Mark|title=Pterosaurs: Natural History, Evolution, Anatomy|publisher=Princeton University Press|year=2013|isbn=978-0-691-15061-1}}
==External links==
* [https://web.archive.org/web/20070322195214/http://www.pterosaur.co.uk/species/UCP/UCP.htm Nyctosauridae (scroll down)] in The Pterosaur Database
{{Pterosauria|P.}}
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[[Category:Pteranodontians]]
[[Category:Late Cretaceous pterosaurs of North America]]
[[Category:Taxa named by Othniel Charles Marsh]]
[[Category:Fossil taxa described in 1876]]