Macroelongatoolithus

<h2 id="history-of-discovery">History of discovery</h2>

"<a href="/facts/Oolithes/uc9GWCcW">Oolithes</a>" carlylensis was described in <a href="/facts/1970_in_paleontology/roRdUCGA">1970</a> by <a href="/facts/James_A._Jensen/ohjxdQkn">James Jensen</a>.<a class="footnote-ref" id="fnref:1" href="#fn:1">1</a> In <a href="/facts/1998_in_paleontology/XhXQtGoT">1998</a>, O. carlylensis was moved to a new oogenus, Boletuoolithus, which was then classified as a <a href="/facts/Spheroolithidae/dL6zoYxy">Spheroolithid</a>.<a class="footnote-ref" id="fnref:2" href="#fn:2">2</a> Macroelongatoolithus was first described in <a href="/facts/1995_in_paleontology/QdCDohak">1995</a> by Li et al., with a single oospecies: M. xixiaensis. It was classified in the oofamily Elongatoolithidae.<a class="footnote-ref" id="fnref:3" href="#fn:3">3</a> Later in the same year, Wang and Zhou described Longiteresoolithus xixiaensis, which they placed into a new oofamily, Macroelongatoolithidae. These three oospecies are now considered <a href="/facts/Synonym_(taxonomy)/BHLdox7E">synonymous</a>, and generally classified in Elongatoolithidae. Since M. carlylensis was named first, it has <a href="/facts/Principle_of_Priority/bfHpKEDK">priority</a>, but the name was corrected to M. carlylei to follow <a href="/facts/International_Code_of_Zoological_Nomenclature/Pxg8gsqf">ICZN</a> provisions.<a class="footnote-ref" id="fnref:4" href="#fn:4">4</a><a class="footnote-ref" id="fnref:5" href="#fn:5">5</a>

<h2 id="description">Description</h2>

Macroelongatoolithus eggs are most notable for their large size. They are at least 34 centimetres (13 in) long, but the largest specimens are over 60 centimetres (24 in) long.<a class="footnote-ref" id="fnref:6" href="#fn:6">6</a><a class="footnote-ref" id="fnref:7" href="#fn:7">7</a><a class="footnote-ref" id="fnref:8" href="#fn:8">8</a> They are also very elongated, usually roughly three times longer than they are wide. They are often found in large <a href="/facts/Egg_clutch/suAybckh">clutches</a> of up to 26 eggs, with the eggs forming a ring 2–3.3 metres (6.6–10.8 ft) in diameter. The shell is typically between 1.38 mm and 4.75 mm thick.<a class="footnote-ref" id="fnref:9" href="#fn:9">9</a><a class="footnote-ref" id="fnref:10" href="#fn:10">10</a><a class="footnote-ref" id="fnref:11" href="#fn:11">11</a>
Like other <a href="/facts/Elongatoolithidae/LWPxHeF6">elongatoolithids</a>, Macroelongatoolithus's eggshell is divided up into two structural layers, and the outer layer (called the continuous layer) is not divided up into distinct shell units, unlike other oofamilies. In Macroelongatoolithus, the boundary between the continuous layer and the mammillary layer (the inner layer of the eggshell, also called the cone layer) is wavy, but clearly defined. The ratio of the thickness of the two layers varies from 2:1 to 8:1.<a class="footnote-ref" id="fnref:12" href="#fn:12">12</a><a class="footnote-ref" id="fnref:13" href="#fn:13">13</a>
The surface ornamentation of the eggshells is variable, even on a single egg. It is usually lineartuberculate (nodes forming linear ridges), ramotuberculate (nodes forming irregular, meandering chains), or dispersituberculate (scattered nodes).<a class="footnote-ref" id="fnref:14" href="#fn:14">14</a><a class="footnote-ref" id="fnref:15" href="#fn:15">15</a>
Macroelongatoolithus specimens are extremely variable in size, shape, and microstructure, even in eggs laid by a single individual. For example, within a single clutch, the egg lengths can vary by several centimeters. The high amount of variability is probably due to their large size.<a class="footnote-ref" id="fnref:16" href="#fn:16">16</a>

<h2 id="classification">Classification</h2>
Macroelongatoolithus has a convoluted parataxonomic history. Several oospecies have been described, but currently they are all considered synonyms of M. carlylei. While it is occasionally classified into a separate oofamily, Macroelongatoolithidae, the general consensus is that it is a member of Elongatoolithidae.<a class="footnote-ref" id="fnref:17" href="#fn:17">17</a> Two other oospecies have also been described: M. zhangi and M. goseongensis, but both are now considered <a href="/facts/Synonym_(taxonomy)/BHLdox7E">synonymous</a> with M. carlylensis.<a class="footnote-ref" id="fnref:18" href="#fn:18">18</a> The oogenus and oospecies Megafusoolithus qiaoxiaensis is also a <a href="/facts/Junior_synonym/BHLdox7E">junior synonym</a> of Macroelongatoolithus carlylei.<a class="footnote-ref" id="fnref:19" href="#fn:19">19</a>

<h2 id="paleobiology">Paleobiology</h2>

While they were once considered to be the eggs of large <a href="/facts/Tyrannosaurids/6Dm2ljv7">tyrannosaurids</a> (like <a href="/facts/Tarbosaurus/6thHRwdJ">Tarbosaurus</a>) on the basis of their huge size,<a class="footnote-ref" id="fnref:20" href="#fn:20">20</a> egg shape and microstructural evidence suggests they are eggs of gigantic <a href="/facts/Oviraptorosaur/C6puS7KW">oviraptorosaurs</a> (like <a href="/facts/Beibeilong/NdwBWTTk">Beibeilong</a> or <a href="/facts/Gigantoraptor/nGoVWf7R">Gigantoraptor</a>).<a class="footnote-ref" id="fnref:21" href="#fn:21">21</a> Macroelongatoolithus eggs closely resemble those of <a href="/facts/Oviraptorids/lhJLvvTb">oviraptorids</a> (<a href="/facts/Elongatoolithidae/LWPxHeF6">Elongatoolithidae</a>),<a class="footnote-ref" id="fnref:22" href="#fn:22">22</a> which are largely known for their brooding adult-nest associations, <a href="/facts/Embryo/9QHnLVLN">embryonic</a> remains, and unique nests.<a class="footnote-ref" id="fnref:23" href="#fn:23">23</a> In 2017 the caenagnathid Beibeilong was described, based on an embryonic specimen (named "Baby Louie") associated with 6 to 8 Macroelongatoolithus eggs and partial nest. The discovery of Beibeilong further concludes that the oogenus Macroelongatoolithus was laid by large oviraptorosaurs, in this case caenagnathids.<a class="footnote-ref" id="fnref:24" href="#fn:24">24</a>
The gas conductance of the eggshells indicate that Macroelongatoolithus nests were buried in vegetation or sediments. Like other elongatoolithids, Macroelongatoolithus eggs are laid in pairs because the parents had two functional <a href="/facts/Oviduct/JRHneIPq">oviducts</a> and thus laid two eggs simultaneously. The nests have unusually large volume of eggs compared to the body size of the parents, which could mean that multiple females would contribute to a single nest. Association of other oviraptorids with their eggs suggests extensive parental care was typical for elongatoolithids.<a class="footnote-ref" id="fnref:25" href="#fn:25">25</a>

 
In 2018, Kohei Tanaka and team examined the <a href="/facts/Egg_clutches/suAybckh">egg clutches</a> of numerous oviraptorosaur specimens, including egg clutches of Macroelongatoolithus, in order to correlate the <a href="/facts/Nest/7tq5lt4V">nest</a> configuration and body size to <a href="/facts/Egg_incubation/E6sRJBSn">incubation behaviour</a>. Their results showed that eggshell porosity indicates that the <a href="/facts/Egg/KyMSx9v4">eggs</a> of almost certainly all oviraptorosaurs were exposed in the nest without an external covering. Though most oviraptorosaur nests have eggs arranged in a circular fashion, the morphology of the nest is different in smaller and larger species in that the center of the nest is highly reduced in the former species, and becomes significantly larger in the latter species. This nest configuration suggest that whereas smallest oviraptorosaurs probably sat directly on the eggs, a large, Gigantoraptor-sized animal likely sat on the area devoid of eggs. Tanaka and colleagues pointed out that this adaption was beneficial to avoid egg-crushing and could have allowed some body-contact during incubation in these giant oviraptorosaurs.<a class="footnote-ref" id="fnref:26" href="#fn:26">26</a>

<h2 id="paleoecology">Paleoecology</h2>
<h3>Distribution</h3>
Macroelongatoolithus eggs have been found in the <a href="/facts/United_States/P0sCdLe5">United States</a>, <a href="/facts/China/lTjIXY5p">China</a>, and <a href="/facts/South_Korea/pCobAaVw">South Korea</a>, ranging in age from <a href="/facts/Early_Cretaceous/5uWEJGYC">Early Cretaceous</a> to <a href="/facts/Maastrichtian/xRBafamu">Maastrichtian</a>.<a class="footnote-ref" id="fnref:27" href="#fn:27">27</a> More specifically, it is known in North America from the <a href="/facts/Cedar_Mountain_Formation/WggxTbUy">Cedar Mountain</a>, <a href="/facts/Dakota_Formation/h6mJJruP">Dakota</a>, <a href="/facts/Kelvin_Formation/t3mTDzRC">Kelvin</a>, and <a href="/facts/Naturita_Formation/EnXtsqFN">Naturita Formations</a> of <a href="/facts/Utah/te7zUyBX">Utah</a>,<a class="footnote-ref" id="fnref:28" href="#fn:28">28</a><a class="footnote-ref" id="fnref:29" href="#fn:29">29</a> the <a href="/facts/Wayan_Formation/Qzg36Pj9">Wayan Formation</a> of <a href="/facts/Idaho/68ELs9Um">Idaho</a>, the <a href="/facts/Blackleaf_Formation/NGy2oT60">Blackleaf Formation</a> of <a href="/facts/Montana/jPFKMuK5">Montana</a>, the <a href="/facts/Thomas_Fork_Formation/Mq1WvaGK">Thomas Fork Formation</a> of Wyoming,<a class="footnote-ref" id="fnref:30" href="#fn:30">30</a> and the <a href="/facts/Willow_Tank_Formation/FAGXjswR">Willow Tank Formation</a> of <a href="/facts/Nevada/HNWhCrQv">Nevada</a>.<a class="footnote-ref" id="fnref:31" href="#fn:31">31</a> In China, it is known from the <a href="/facts/Liangtoutang_Formation/K9DVB2Av">Liangtoutang</a> and Chichengshan Formations in <a href="/facts/Tiantai_County/keBvDtQv">Tiantai County</a>, <a href="/facts/Zhejiang_Province/TQtpFHdJ">Zhejiang Province</a>,<a class="footnote-ref" id="fnref:32" href="#fn:32">32</a><a class="footnote-ref" id="fnref:33" href="#fn:33">33</a> from the <a href="/facts/Gaogou_Formation/5CqLUrH2">Gaogou</a>, <a href="/facts/Sigou_Formation/S7RT6A0G">Sigou</a>, <a href="/facts/Majiacun_Formation/pCbJHkB3">Majiacun</a>, and <a href="/facts/Zoumagang_Formation/vFf769n0">Zoumagang Formations</a> in <a href="/facts/Henan_Province/jCKtYLXv">Henan Province</a>, <a href="/facts/China/lTjIXY5p">China</a>.<a class="footnote-ref" id="fnref:34" href="#fn:34">34</a><a class="footnote-ref" id="fnref:35" href="#fn:35">35</a><a class="footnote-ref" id="fnref:36" href="#fn:36">36</a> It is known in South Korea from the Goseong Formation near <a href="/facts/Tongyeong/X8apgXr2">Tongyeong</a> and from Aphae-do in Shinan-gun, Jeollanam-do Province.<a class="footnote-ref" id="fnref:37" href="#fn:37">37</a><a class="footnote-ref" id="fnref:38" href="#fn:38">38</a>
The presence of Macroelongatoolithus in the United States indicates that there was likely a giant oviraptorosaur present during the <a href="/facts/Late_Cretaceous/pcHa4fBg">Late Cretaceous</a> in <a href="/facts/North_America/djNjCQIl">North America</a>. Also, the fact that they have been found in both <a href="/facts/Asia/4IToYrrQ">Asia</a> and North America is evidence of an <a href="/facts/Albian/faHcmHDC">Albian</a>-<a href="/facts/Cenomanian/atR50Pe7">Cenomanian</a> interchange of fauna between the two continents.<a class="footnote-ref" id="fnref:39" href="#fn:39">39</a><a class="footnote-ref" id="fnref:40" href="#fn:40">40</a><a class="footnote-ref" id="fnref:41" href="#fn:41">41</a>

<h2 id="see-also">See also</h2>
<ul>
<li>Dinosaurs portal</li></ul>
<ul><li><a href="/facts/List_of_dinosaur_oogenera/nH5XHNRS">List of dinosaur oogenera</a></li>
<li><a href="/facts/Elephant_bird/sF8rFpao">Elephant bird</a>, the avian dinosaur that laid the largest egg.</li></ul>

<h2 id="external-links">External links</h2>
<ul><li> Media related to Macroelongatoolithus at Wikimedia Commons</li>
<li> Data related to Macroelongatoolithus at Wikispecies</li></ul>

<h2 id="references">References</h2>

<ol>
<li id="fn:1">Jensen J. 1970. Fossil eggs in the lower cretaceous of Utah. Brigham Young University research studies. Geology Series. Geology Studies 17: 51-65. <a href="#fnref:1" class="footnote-back-ref">↩</a></li>
<li id="fn:2">Bray, E. S. 1998. Dinosaur eggshell Boletuoolithus carlylensis, oogen. nov. from the Lower Cretaceous Cedar Mountain Formation of Utah; pp. 221–223 in S. G. Lucas, J. I. Kirkland, and J. W. Estep
(eds.), Lower and Middle Cretaceous Terrestrial Ecosystems. New Mexico Museum of Natural History and Science Bulletin No. 14. <a href="#fnref:2" class="footnote-back-ref">↩</a></li>
<li id="fn:3">Li Y, Yin Z, Liu Y. (1995) "The discovery of a new genus of dinosaur egg from Xixia, Henan, China." Journal of Wuhan Institute of Chemical Technology 17(1): 38-41. (In Chinese) <a href="#fnref:3" class="footnote-back-ref">↩</a></li>
<li id="fn:4">Simon, D. J. (2014). "Giant Dinosaur (theropod) Eggs of the Oogenus Macroelongatoolithus (Elongatoolithidae) from Southeastern Idaho: Taxonomic, Paleobiogeographic, and Reproductive Implications" (PDF). Doctoral Dissertation, Montana State University. Bozeman. Archived (PDF) from the original on 11 August 2021. <a href="https://scholarworks.montana.edu/xmlui/bitstream/handle/1/8693/SimonD0814.pdf" target="_blank">https://scholarworks.montana.edu/xmlui/bitstream/handle/1/8693/SimonD0814.pdf</a> <a href="#fnref:4" class="footnote-back-ref">↩</a></li>
<li id="fn:5">Zelenitsky DK, Carpenter K, Currie PJ. (2000) "First record of Elongatoolithid theropod eggshell from North America: the Asian oogenus Macroelongatoolithus from the lower Cretaceous of Utah." Journal of Vertebrate Paleontology 20(1): 130-138. <a href="/wiki/Journal_of_Vertebrate_Paleontology" target="_blank">/wiki/Journal_of_Vertebrate_Paleontology</a> <a href="#fnref:5" class="footnote-back-ref">↩</a></li>
<li id="fn:6">Carpenter, K. 1999. Eggs, Nests, and Baby Dinosaurs: A Look at Dinosaur Reproduction (Life of the Past). Indiana University Press, Bloomington, Indiana. <a href="#fnref:6" class="footnote-back-ref">↩</a></li>
<li id="fn:7">Simon, D. J. (2014). "Giant Dinosaur (theropod) Eggs of the Oogenus Macroelongatoolithus (Elongatoolithidae) from Southeastern Idaho: Taxonomic, Paleobiogeographic, and Reproductive Implications" (PDF). Doctoral Dissertation, Montana State University. Bozeman. Archived (PDF) from the original on 11 August 2021. <a href="https://scholarworks.montana.edu/xmlui/bitstream/handle/1/8693/SimonD0814.pdf" target="_blank">https://scholarworks.montana.edu/xmlui/bitstream/handle/1/8693/SimonD0814.pdf</a> <a href="#fnref:7" class="footnote-back-ref">↩</a></li>
<li id="fn:8">Pu, H.; Zelenitsky, D. K.; Lü, J.; Currie, P. J.; Carpenter, K.; Xu, L.; Koppelhus, E. B.; Jia, S.; Xiao, L.; Chuang, H.; Li, T.; Kundrát, M.; Shen, C. (2017). "Perinate and eggs of a giant caenagnathid dinosaur from the Late Cretaceous of central China". Nature Communications. 8 (14952): 14952. Bibcode:2017NatCo...814952P. doi:10.1038/ncomms14952. PMC 5477524. PMID 28486442. <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5477524" target="_blank">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5477524</a> <a href="#fnref:8" class="footnote-back-ref">↩</a></li>
<li id="fn:9">Simon, D. J. (2014). "Giant Dinosaur (theropod) Eggs of the Oogenus Macroelongatoolithus (Elongatoolithidae) from Southeastern Idaho: Taxonomic, Paleobiogeographic, and Reproductive Implications" (PDF). Doctoral Dissertation, Montana State University. Bozeman. Archived (PDF) from the original on 11 August 2021. <a href="https://scholarworks.montana.edu/xmlui/bitstream/handle/1/8693/SimonD0814.pdf" target="_blank">https://scholarworks.montana.edu/xmlui/bitstream/handle/1/8693/SimonD0814.pdf</a> <a href="#fnref:9" class="footnote-back-ref">↩</a></li>
<li id="fn:10">Zelenitsky DK, Carpenter K, Currie PJ. (2000) "First record of Elongatoolithid theropod eggshell from North America: the Asian oogenus Macroelongatoolithus from the lower Cretaceous of Utah." Journal of Vertebrate Paleontology 20(1): 130-138. <a href="/wiki/Journal_of_Vertebrate_Paleontology" target="_blank">/wiki/Journal_of_Vertebrate_Paleontology</a> <a href="#fnref:10" class="footnote-back-ref">↩</a></li>
<li id="fn:11">Simon, D. J.; Varricchio, D. J.; Jin, X.; Robinson, S. F. (2019). "Microstructural overlap of Macroelongatoolithus eggs from Asia and North America expands the occurrence of colossal oviraptorosaurs". Journal of Vertebrate Paleontology. 38 (6): e1553046. doi:10.1080/02724634.2018.1553046. S2CID 191155027. <a href="/wiki/Doi_(identifier)" target="_blank">/wiki/Doi_(identifier)</a> <a href="#fnref:11" class="footnote-back-ref">↩</a></li>
<li id="fn:12">Simon, D. J. (2014). "Giant Dinosaur (theropod) Eggs of the Oogenus Macroelongatoolithus (Elongatoolithidae) from Southeastern Idaho: Taxonomic, Paleobiogeographic, and Reproductive Implications" (PDF). Doctoral Dissertation, Montana State University. Bozeman. Archived (PDF) from the original on 11 August 2021. <a href="https://scholarworks.montana.edu/xmlui/bitstream/handle/1/8693/SimonD0814.pdf" target="_blank">https://scholarworks.montana.edu/xmlui/bitstream/handle/1/8693/SimonD0814.pdf</a> <a href="#fnref:12" class="footnote-back-ref">↩</a></li>
<li id="fn:13">Simon, D. J.; Varricchio, D. J.; Jin, X.; Robinson, S. F. (2019). "Microstructural overlap of Macroelongatoolithus eggs from Asia and North America expands the occurrence of colossal oviraptorosaurs". Journal of Vertebrate Paleontology. 38 (6): e1553046. doi:10.1080/02724634.2018.1553046. S2CID 191155027. <a href="/wiki/Doi_(identifier)" target="_blank">/wiki/Doi_(identifier)</a> <a href="#fnref:13" class="footnote-back-ref">↩</a></li>
<li id="fn:14">Simon, D. J. (2014). "Giant Dinosaur (theropod) Eggs of the Oogenus Macroelongatoolithus (Elongatoolithidae) from Southeastern Idaho: Taxonomic, Paleobiogeographic, and Reproductive Implications" (PDF). Doctoral Dissertation, Montana State University. Bozeman. Archived (PDF) from the original on 11 August 2021. <a href="https://scholarworks.montana.edu/xmlui/bitstream/handle/1/8693/SimonD0814.pdf" target="_blank">https://scholarworks.montana.edu/xmlui/bitstream/handle/1/8693/SimonD0814.pdf</a> <a href="#fnref:14" class="footnote-back-ref">↩</a></li>
<li id="fn:15">Simon, D. J.; Varricchio, D. J.; Jin, X.; Robinson, S. F. (2019). "Microstructural overlap of Macroelongatoolithus eggs from Asia and North America expands the occurrence of colossal oviraptorosaurs". Journal of Vertebrate Paleontology. 38 (6): e1553046. doi:10.1080/02724634.2018.1553046. S2CID 191155027. <a href="/wiki/Doi_(identifier)" target="_blank">/wiki/Doi_(identifier)</a> <a href="#fnref:15" class="footnote-back-ref">↩</a></li>
<li id="fn:16">Zelenitsky DK, Carpenter K, Currie PJ. (2000) "First record of Elongatoolithid theropod eggshell from North America: the Asian oogenus Macroelongatoolithus from the lower Cretaceous of Utah." Journal of Vertebrate Paleontology 20(1): 130-138. <a href="/wiki/Journal_of_Vertebrate_Paleontology" target="_blank">/wiki/Journal_of_Vertebrate_Paleontology</a> <a href="#fnref:16" class="footnote-back-ref">↩</a></li>
<li id="fn:17">Simon, D. J. (2014). "Giant Dinosaur (theropod) Eggs of the Oogenus Macroelongatoolithus (Elongatoolithidae) from Southeastern Idaho: Taxonomic, Paleobiogeographic, and Reproductive Implications" (PDF). Doctoral Dissertation, Montana State University. Bozeman. Archived (PDF) from the original on 11 August 2021. <a href="https://scholarworks.montana.edu/xmlui/bitstream/handle/1/8693/SimonD0814.pdf" target="_blank">https://scholarworks.montana.edu/xmlui/bitstream/handle/1/8693/SimonD0814.pdf</a> <a href="#fnref:17" class="footnote-back-ref">↩</a></li>
<li id="fn:18">Simon, D. J. (2014). "Giant Dinosaur (theropod) Eggs of the Oogenus Macroelongatoolithus (Elongatoolithidae) from Southeastern Idaho: Taxonomic, Paleobiogeographic, and Reproductive Implications" (PDF). Doctoral Dissertation, Montana State University. Bozeman. Archived (PDF) from the original on 11 August 2021. <a href="https://scholarworks.montana.edu/xmlui/bitstream/handle/1/8693/SimonD0814.pdf" target="_blank">https://scholarworks.montana.edu/xmlui/bitstream/handle/1/8693/SimonD0814.pdf</a> <a href="#fnref:18" class="footnote-back-ref">↩</a></li>
<li id="fn:19">Simon, D. J. (2014). "Giant Dinosaur (theropod) Eggs of the Oogenus Macroelongatoolithus (Elongatoolithidae) from Southeastern Idaho: Taxonomic, Paleobiogeographic, and Reproductive Implications" (PDF). Doctoral Dissertation, Montana State University. Bozeman. Archived (PDF) from the original on 11 August 2021. <a href="https://scholarworks.montana.edu/xmlui/bitstream/handle/1/8693/SimonD0814.pdf" target="_blank">https://scholarworks.montana.edu/xmlui/bitstream/handle/1/8693/SimonD0814.pdf</a> <a href="#fnref:19" class="footnote-back-ref">↩</a></li>
<li id="fn:20">Qian, M. P., Jiang, Y., Jiang, Y. G., Zhang, Y. J., Chen, R., Li, L. M., and Xing, G. F. (2008). "New evidence on fossil eggs of Cretaceous Tyrannosaurs in eastern China." Jiangsu Geology, 32: 86-97. <a href="#fnref:20" class="footnote-back-ref">↩</a></li>
<li id="fn:21">Pu, H.; Zelenitsky, D. K.; Lü, J.; Currie, P. J.; Carpenter, K.; Xu, L.; Koppelhus, E. B.; Jia, S.; Xiao, L.; Chuang, H.; Li, T.; Kundrát, M.; Shen, C. (2017). "Perinate and eggs of a giant caenagnathid dinosaur from the Late Cretaceous of central China". Nature Communications. 8 (14952): 14952. Bibcode:2017NatCo...814952P. doi:10.1038/ncomms14952. PMC 5477524. PMID 28486442. <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5477524" target="_blank">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5477524</a> <a href="#fnref:21" class="footnote-back-ref">↩</a></li>
<li id="fn:22">Grellet-Tinner, G., Chiappe, L., Norell, M., and Bottjer, D. (2006). "Dinosaur eggs and nesting behaviors: a paleobiological investigation." Palaeogeography, Palaeoclimatology, Palaeoecology, 232(2): 294-321. <a href="https://www.researchgate.net/profile/Mark_Norell/publication/222646157_Dinosaur_eggs_and_nesting_behaviors_A_paleobiological_investigation/links/02bfe511a934b8a9c9000000.pdf" target="_blank">https://www.researchgate.net/profile/Mark_Norell/publication/222646157_Dinosaur_eggs_and_nesting_behaviors_A_paleobiological_investigation/links/02bfe511a934b8a9c9000000.pdf</a> <a href="#fnref:22" class="footnote-back-ref">↩</a></li>
<li id="fn:23">Simon, D. J. (2014). "Giant Dinosaur (theropod) Eggs of the Oogenus Macroelongatoolithus (Elongatoolithidae) from Southeastern Idaho: Taxonomic, Paleobiogeographic, and Reproductive Implications" (PDF). Doctoral Dissertation, Montana State University. Bozeman. Archived (PDF) from the original on 11 August 2021. <a href="https://scholarworks.montana.edu/xmlui/bitstream/handle/1/8693/SimonD0814.pdf" target="_blank">https://scholarworks.montana.edu/xmlui/bitstream/handle/1/8693/SimonD0814.pdf</a> <a href="#fnref:23" class="footnote-back-ref">↩</a></li>
<li id="fn:24">Pu, H.; Zelenitsky, D. K.; Lü, J.; Currie, P. J.; Carpenter, K.; Xu, L.; Koppelhus, E. B.; Jia, S.; Xiao, L.; Chuang, H.; Li, T.; Kundrát, M.; Shen, C. (2017). "Perinate and eggs of a giant caenagnathid dinosaur from the Late Cretaceous of central China". Nature Communications. 8 (14952): 14952. Bibcode:2017NatCo...814952P. doi:10.1038/ncomms14952. PMC 5477524. PMID 28486442. <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5477524" target="_blank">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5477524</a> <a href="#fnref:24" class="footnote-back-ref">↩</a></li>
<li id="fn:25">Simon, D. J. (2014). "Giant Dinosaur (theropod) Eggs of the Oogenus Macroelongatoolithus (Elongatoolithidae) from Southeastern Idaho: Taxonomic, Paleobiogeographic, and Reproductive Implications" (PDF). Doctoral Dissertation, Montana State University. Bozeman. Archived (PDF) from the original on 11 August 2021. <a href="https://scholarworks.montana.edu/xmlui/bitstream/handle/1/8693/SimonD0814.pdf" target="_blank">https://scholarworks.montana.edu/xmlui/bitstream/handle/1/8693/SimonD0814.pdf</a> <a href="#fnref:25" class="footnote-back-ref">↩</a></li>
<li id="fn:26">Tanaka, K.; Zelenitsky, D. K.; Lü, J.; DeBuhr, C. L.; Yi, L.; Jia, S.; Ding, F.; Xia, M.; Liu, D.; Shen, C.; Chen, R. (2018). "Incubation behaviours of oviraptorosaur dinosaurs in relation to body size". Biology Letters. 14 (5): 20180135. doi:10.1098/rsbl.2018.0135. PMC 6012691. PMID 29769301. <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6012691" target="_blank">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6012691</a> <a href="#fnref:26" class="footnote-back-ref">↩</a></li>
<li id="fn:27">Simon, D. J. (2014). "Giant Dinosaur (theropod) Eggs of the Oogenus Macroelongatoolithus (Elongatoolithidae) from Southeastern Idaho: Taxonomic, Paleobiogeographic, and Reproductive Implications" (PDF). Doctoral Dissertation, Montana State University. Bozeman. Archived (PDF) from the original on 11 August 2021. <a href="https://scholarworks.montana.edu/xmlui/bitstream/handle/1/8693/SimonD0814.pdf" target="_blank">https://scholarworks.montana.edu/xmlui/bitstream/handle/1/8693/SimonD0814.pdf</a> <a href="#fnref:27" class="footnote-back-ref">↩</a></li>
<li id="fn:28">Zelenitsky DK, Carpenter K, Currie PJ. (2000) "First record of Elongatoolithid theropod eggshell from North America: the Asian oogenus Macroelongatoolithus from the lower Cretaceous of Utah." Journal of Vertebrate Paleontology 20(1): 130-138. <a href="/wiki/Journal_of_Vertebrate_Paleontology" target="_blank">/wiki/Journal_of_Vertebrate_Paleontology</a> <a href="#fnref:28" class="footnote-back-ref">↩</a></li>
<li id="fn:29">Hedge, Joshua; Tucker, Ryan T.; Makovicky, Peter J.; Zanno, Lindsay E. (2025-02-26). "Fossil eggshell diversity of the Mussentuchit Member, Cedar Mountain Formation, Utah". PLOS ONE. 20 (2) e0314689. doi:10.1371/journal.pone.0314689. PMC 11864547. PMID 40009577. <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11864547" target="_blank">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11864547</a> <a href="#fnref:29" class="footnote-back-ref">↩</a></li>
<li id="fn:30">Simon, D. J. (2014). "Giant Dinosaur (theropod) Eggs of the Oogenus Macroelongatoolithus (Elongatoolithidae) from Southeastern Idaho: Taxonomic, Paleobiogeographic, and Reproductive Implications" (PDF). Doctoral Dissertation, Montana State University. Bozeman. Archived (PDF) from the original on 11 August 2021. <a href="https://scholarworks.montana.edu/xmlui/bitstream/handle/1/8693/SimonD0814.pdf" target="_blank">https://scholarworks.montana.edu/xmlui/bitstream/handle/1/8693/SimonD0814.pdf</a> <a href="#fnref:30" class="footnote-back-ref">↩</a></li>
<li id="fn:31">Bonde, Varricchio and Jackson, Loope, Shirk, Joshua W., Frankie D. and David J., David B., and Aubrey M. (January 2008). "Dinosaurs and dunes! Sedimentology and paleontology of the Mesozoic in the Valley of Fire State Park". GSA Field Guide 11: Field Guide to Plutons, Volcanoes, Faults, Reefs, Dinosaurs, and Possible Glaciation in Selected Areas of Arizona, California, and Nevada. Vol. 11. pp. 249–262. doi:10.1130/2008.fld011(11). ISBN 978-0-8137-0011-3.{{cite book}}: CS1 maint: multiple names: authors list (link) <a href="978-0-8137-0011-3" target="_blank">978-0-8137-0011-3</a> <a href="#fnref:31" class="footnote-back-ref">↩</a></li>
<li id="fn:32">X. Jin, Y. Azuma, F. D. Jackson and D. J. Varricchio. (2007) "Giant dinosaur eggs from the Tiantai basin, Zhejiang province, China." Canadian Journal of Earth Sciences 44:81-88. <a href="/wiki/Canadian_Journal_of_Earth_Sciences" target="_blank">/wiki/Canadian_Journal_of_Earth_Sciences</a> <a href="#fnref:32" class="footnote-back-ref">↩</a></li>
<li id="fn:33">Wang Qiang, Zhao Zikui, Wang Xiaolin, Jiang Yangen, and Zhang Shukang. (2010) "A New Oogenus Of Macroelongatoolithid Eggs From The Upper Cretaceous Chichengshan Formation Of The Tiantai Basin, Zhejiang Province And A Revision Of The Macroelongatoolithids" Acta Paleontologica Sinica 49(1)：73-86. <a href="/w/index.php?title=Acta_Paleontologica_Sinica&action=edit&redlink=1" target="_blank">/w/index.php?title=Acta_Paleontologica_Sinica&action=edit&redlink=1</a> <a href="#fnref:33" class="footnote-back-ref">↩</a></li>
<li id="fn:34">Simon, D. J. (2014). "Giant Dinosaur (theropod) Eggs of the Oogenus Macroelongatoolithus (Elongatoolithidae) from Southeastern Idaho: Taxonomic, Paleobiogeographic, and Reproductive Implications" (PDF). Doctoral Dissertation, Montana State University. Bozeman. Archived (PDF) from the original on 11 August 2021. <a href="https://scholarworks.montana.edu/xmlui/bitstream/handle/1/8693/SimonD0814.pdf" target="_blank">https://scholarworks.montana.edu/xmlui/bitstream/handle/1/8693/SimonD0814.pdf</a> <a href="#fnref:34" class="footnote-back-ref">↩</a></li>
<li id="fn:35">Grellet-Tinner, G., Chiappe, L., Norell, M., and Bottjer, D. (2006). "Dinosaur eggs and nesting behaviors: a paleobiological investigation." Palaeogeography, Palaeoclimatology, Palaeoecology, 232(2): 294-321. <a href="https://www.researchgate.net/profile/Mark_Norell/publication/222646157_Dinosaur_eggs_and_nesting_behaviors_A_paleobiological_investigation/links/02bfe511a934b8a9c9000000.pdf" target="_blank">https://www.researchgate.net/profile/Mark_Norell/publication/222646157_Dinosaur_eggs_and_nesting_behaviors_A_paleobiological_investigation/links/02bfe511a934b8a9c9000000.pdf</a> <a href="#fnref:35" class="footnote-back-ref">↩</a></li>
<li id="fn:36">Li, G., Chen, P., Wang, D., & Batten, D. J. (2009). "The spinicaudatan Tylestheria and biostratigraphic significance for the age of dinosaur eggs in the Upper Cretaceous Majiacun Formation, Xixia Basin, Henan Province, China." Cretaceous Research, 30(2): 477-482. <a href="https://www.researchgate.net/profile/David_Batten/publication/248573303_The_spinicaudatan_Tylestheria_and_biostratigraphic_significance_for_the_age_of_dinosaur_eggs_in_the_Upper_Cretaceous_Majiacun_Formation_Xixia_Basin_Henan_Province_China/links/5435254f0cf2dc341daf8068.pdf" target="_blank">https://www.researchgate.net/profile/David_Batten/publication/248573303_The_spinicaudatan_Tylestheria_and_biostratigraphic_significance_for_the_age_of_dinosaur_eggs_in_the_Upper_Cretaceous_Majiacun_Formation_Xixia_Basin_Henan_Province_China/links/5435254f0cf2dc341daf8068.pdf</a> <a href="#fnref:36" class="footnote-back-ref">↩</a></li>
<li id="fn:37">Kim, J. Y., Yang, S. Y., Choi, H. I., Seo, S. J., & Kim, K. S. (2011). Dinosaur eggs from the Cretaceous Goseong formation of Tongyeong City, southern coast of Korea. Journal of the Paleontological Society of Korea 27(1): 13-26. <a href="#fnref:37" class="footnote-back-ref">↩</a></li>
<li id="fn:38">Huh, M., Kim, B. S., Woo, Y., Simon, D. J., Paik, I. S., & Kim, H. J. (2014). First record of a complete giant theropod egg clutch from Upper Cretaceous deposits, South Korea. Historical Biology, 26(2), 218–228. https://doi.org/10.1080/08912963.2014.894998 <a href="https://doi.org/10.1080/08912963.2014.894998" target="_blank">https://doi.org/10.1080/08912963.2014.894998</a> <a href="#fnref:38" class="footnote-back-ref">↩</a></li>
<li id="fn:39">Zelenitsky DK, Carpenter K, Currie PJ. (2000) "First record of Elongatoolithid theropod eggshell from North America: the Asian oogenus Macroelongatoolithus from the lower Cretaceous of Utah." Journal of Vertebrate Paleontology 20(1): 130-138. <a href="/wiki/Journal_of_Vertebrate_Paleontology" target="_blank">/wiki/Journal_of_Vertebrate_Paleontology</a> <a href="#fnref:39" class="footnote-back-ref">↩</a></li>
<li id="fn:40">Simon, D. J. (2014). "Giant Dinosaur (theropod) Eggs of the Oogenus Macroelongatoolithus (Elongatoolithidae) from Southeastern Idaho: Taxonomic, Paleobiogeographic, and Reproductive Implications" (PDF). Doctoral Dissertation, Montana State University. Bozeman. Archived (PDF) from the original on 11 August 2021. <a href="https://scholarworks.montana.edu/xmlui/bitstream/handle/1/8693/SimonD0814.pdf" target="_blank">https://scholarworks.montana.edu/xmlui/bitstream/handle/1/8693/SimonD0814.pdf</a> <a href="#fnref:40" class="footnote-back-ref">↩</a></li>
<li id="fn:41">Simon, D. J.; Varricchio, D. J.; Jin, X.; Robinson, S. F. (2019). "Microstructural overlap of Macroelongatoolithus eggs from Asia and North America expands the occurrence of colossal oviraptorosaurs". Journal of Vertebrate Paleontology. 38 (6): e1553046. doi:10.1080/02724634.2018.1553046. S2CID 191155027. <a href="/wiki/Doi_(identifier)" target="_blank">/wiki/Doi_(identifier)</a> <a href="#fnref:41" class="footnote-back-ref">↩</a></li>
</ol>

Macroelongatoolithus open-in-new

Macroelongatoolithus