526:
118:
1817:
588:
476:
666:
139:
401:
2211:
2194:
505:
small scales, two rows of large, round scutes with shallow keels ran along the animals sides. One row ran directly along the flank, with the other either slightly higher or lower and composed of scutes only 1/4 the size of the flank scutes. The flank row of larger scutes extended all the way to the base of the tail, and remained uniform in size across the entire row.
1837:
647:(four-limbed vertebrate) in the Yixian Formation, and probably played an important role in the aquatic food chain. Its long and highly flexible neck and small, flattened skull indicates that it captured small prey animals like fish or arthropods using a sideways-strike, similar to modern aquatic predators with flattened skulls. Unlike other choristoderans,
719:, which governs the naming of animals, mandates that the older name is valid. However, in June 2001 paleontologists Joshua Smith and Jerry Harris noted that since both were published at almost exactly the same time, a third party needed to select which name would better serve as the objective senior
516:
was described in 2023, which preserves partial scales from most areas of the body. The preserved portion of the head scales were rhomboid in shape, while those of the neck were rectangular. The webbed nature of the feet was confirmed. The integument was considered comparable to that of crocodilians.
504:
was covered mostly in small, irregularly patterned polygonal scales, though these varied across the body. The scales of the hind legs were smaller, finer and more irregular than those of the torso, while the scales of the tail were nearly square and arranged in more regular rows. In addition to the
508:
The tail itself has preserved soft tissue extending well beyond the margins of the skeleton. This, combined with the already flattened appearance of the tail vertebrae, suggests that a ridge of skin may have extended from the top and bottom of the tail creating a small fin. The feet and hands also
494:, and another (with clearer impressions) cannot be assigned to a species because part of the neck (the length of which is a key indicator of species) was destroyed when fossil dealers grafted a skull from a different specimen onto the slab. However, both specimens show nearly identical patterns of
555:
gave birth to live young and that egg shells never fully developed inside the body of the mother. However, in 2006, Ji and colleagues re-examined the holotype specimen and noted clearly defined, though thin and leathery, shells. They agreed, however, that these eggs must have developed inside the
443:
were largely similar in anatomy, both achieved a maximum adult body size of about 0.8 meters. They had small heads with numerous needle-like teeth, and extremely long tails with more than 55 vertebrae. The primary difference between the two species is the number of vertebrae in the neck.
610:
was among the most aquatically adapted choristoderans, with smoother, flatter scales than its relatives, a tall and flattened tail for swimming, a long neck and webbed feet. Because the torso was fairly inflexible and the limbs were not particularly adapted for aquatic life,
571:, described by Ji and colleagues in 2010, appeared to be pregnant, containing 18 fully developed embryos arranged in pairs. One of the rear-most embryos was positioned in a reverse, head-first position, a complication which may have killed the mother. This confirmed that
657:, which may have been a prey item, and at least one specimen preserved fish ribs as stomach contents. However, the lack of preserved stomach contents among the thousands of known specimens may indicate that they ate mainly soft-bodied prey.
692:
551:, several eggs containing embryos were preserved in and around the body. These eggs appeared to lack mineralized shells, which Ji and colleagues later interpreted as evidence that
427:, though subsequent study showed that the fossil beds it was found in might also belong to the Yixian Formation, specifically from younger rocks and a different region than
1604:
Ji, Q.; Ji, S.; Cheng, Y.; You, H.; Lu, J.; Yuan, C. (2004). "The first fossil soft-shell eggs with embryos from Late
Mesozoic Jehol Biota of western Liaoning, China".
629:. All specimens are preserved in silt characteristic of the deepest part of the lake environment, and are often preserved alongside deep-water fish and crustaceans.
2276:
1742:
Smith, J. B.; Harris, J. D. (2001). "A taxonomic problem concerning two diapsid genera from the lower Yixian
Formation of Liaoning Province, northeastern China".
716:
651:
was likely an active predator, rather than one that used a "sit and wait" ambush strategy. Its fossils are often found preserved alongside the small fish
564:
embryos. These shells were soft, and more similar to the eggs of lizards than to those of crocodiles, but nonetheless possessed a thin mineralized shell.
1418:
Ji, Q.; Ji, S.; Lü, J.; You, H.; Yuan, C. (2006). "Embryos of Early
Cretaceous Choristodera (Reptilia) from the Jehol Biota in western Liaoning, China".
560:), but were likely expelled from the body when the mother died. Hou and colleagues (2010) also described several eggs with flexible shells, containing
2263:
727:
as the senior synonym because the manuscript for its description had apparently been submitted (though not published) earlier. They therefore made
1878:
615:
probably swam using mainly its tall, flattened tail. The chest was barrel-shaped and made up of thick, heavy rib bones which would have helped
602:
species were aquatic, a lifestyle reflected by their long necks and tails and relatively small limbs. Superficially, they resembled miniature
1575:"A new specimen of the Early Cretaceous long-necked choristodere Hyphalosaurus from Liaoning, China with exceptionally-preserved integument"
2330:
2350:
126:
2340:
699:. Each team described the taxon and published their results independently in January 1999, giving the animal two different names:
696:
419:
specimens are known from the Yixian
Formation, including entire growth series from embryos in eggs to fully grown adults.
411:
fossils are relatively widespread in the Jehol beds, which represent a series of freshwater lakes. Several specimens of
138:
1683:
Ji, Qiang; Wu, Xiao-chun; Cheng, Yen-nien (2010-02-24). "Cretaceous choristoderan reptiles gave birth to live young".
1871:
1382:
from the Lower
Cretaceous Jiufotang Formation of western Liaoning, China and its paleobiogeographic significance"
1755:
1841:
673:
2193:
525:
633:
is also conspicuously absent from the aquatic sediments of the
Jiufotang Formation, which preserved a more
2231:
1769:
Dong, Liping; Matsumoto, Ryoko; Kusuhashi, Nao; Wang, Yuanqing; Wang, Yuan; Evans, Susan E. (2020-08-02).
2345:
2335:
2302:
2214:
1864:
400:
1770:
1692:
715:
were mirror images of one another and in fact represented different halves of the same specimen. The
117:
1960:
1822:
424:
377:
587:
1798:
1724:
1574:
720:
299:
133:
2307:
475:
665:
2289:
2281:
2105:
1790:
1716:
1708:
1665:
1647:
1555:
1537:
1493:
1475:
1224:
381:
2294:
1847:
2068:
1782:
1751:
1700:
1655:
1639:
1586:
1545:
1529:
1483:
1467:
1393:
373:
365:
30:
2160:
2123:
1626:
Hou, Lian-Hai; Li, Pi-Peng; Ksepka, Daniel T.; Gao, Ke-Qin; Norell, Mark A. (2010-04-22).
1520:
875:
495:
206:
1771:"A new choristodere (Reptilia: Choristodera) from an Aptian–Albian coal deposit in China"
1696:
1573:
Wang, Miaoyan; Xing, Lida; Niu, Kecheng; Liang, Qingqing; Evans, Susan E. (April 2023).
606:, though this resemblance arose convergently and does not reflect a close relationship.
2098:
2050:
1660:
1627:
1550:
1515:
1488:
1451:
1089:
836:
556:
mother which would later have given live birth (a reproductive method sometimes called
334:
455:
In 2007, the UK Royal
Society announced that it had discovered a two-headed fossil of
2324:
2167:
2132:
2112:
2091:
2036:
1802:
1471:
1147:
1074:
1003:
952:
854:
749:
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68:
2153:
2139:
2023:
1998:
1972:
1887:
1728:
889:
345:
232:
193:
1786:
1590:
2057:
2043:
811:
768:
490:
have been described with clear impressions of the skin. One specimen represents
464:
460:
392:
specimens representing all growth stages in scientific and private collections.
388:. They are among the best-known animals from the Jehol Biota, with thousands of
43:
2146:
1945:
1923:
1812:
1704:
1398:
1377:
764:
603:
576:
540:
have been recovered from the Yixian
Formation, dating 122 million years ago.
349:
331:
88:
53:
2254:
1794:
1712:
1651:
1628:"Implications of flexible-shelled eggs in a Cretaceous choristoderan reptile"
1541:
1479:
653:
579:, the only known Mesozoic fresh-water reptiles to give birth to live young.
353:
150:
93:
37:
1720:
1669:
1643:
1559:
1533:
1497:
463:
that such a reptile has been found fossilized and the oldest known case of
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2248:
2174:
1917:
1911:
922:
680:
644:
544:
170:
83:
78:
63:
58:
48:
2268:
2084:
1929:
1280:
784:
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688:
360:
age), about 123-120 million years ago. The genus contains two species,
341:
337:
255:
180:
98:
73:
1456:(Diapsida: Choristodera) from the Lower Cretaceous of Liaoning, China"
1905:
776:
772:
389:
357:
160:
2225:
1514:
Buffetaut, Eric; Li, Jianjun; Tong, Haiyan; Zhang, He (2007-02-22).
780:
760:
664:
634:
586:
524:
474:
399:
385:
327:
1632:
Proceedings of the Royal
Society of London B: Biological Sciences
759:, from the Early Cretaceous of Japan. The choristoderes were a
626:
2229:
1898:
1860:
1856:
723:. Smith and Harris took the opportunity to do so, selecting
1756:
10.1671/0272-4634(2001)021[0389:ATPCTD]2.0.CO;2
790:
Phylogeny from the analysis of Dong and colleagues (2020):
693:
Institute of
Vertebrate Paleontology and Paleoanthropology
753:. Its closest relative was the similarly built species,
1445:
1443:
1441:
1439:
1437:
1435:
1433:
280:
264:
239:
2238:
2122:
2067:
2022:
1971:
1944:
1516:"A two-headed reptile from the Cretaceous of China"
431:. However, a 2024 study confirmed the presence of
687:were given to different groups of researchers in
625:appears to have exclusively inhabited deep-water
1420:Journal of the Paleontological Society of Korea
536:Numerous embryonic and/or newborn specimens of
1376:Zhang, L.-J.; Ji, S.-A.; Zhang, H.-C. (2024).
1872:
1621:
1619:
8:
1450:Gao, Ke-Qin; Ksepka, Daniel T. (June 2008).
1413:
1411:
1409:
16:Genus of extinct freshwater aquatic reptiles
1509:
1507:
1371:
1369:
2226:
2028:
2019:
2015:
1950:
1941:
1895:
1879:
1865:
1857:
783:. The choristoderes became extinct by the
763:of aquatic reptiles that survived the end-
116:
20:
1659:
1549:
1487:
1397:
423:was originally reported from the younger
741:is related to the large, crocodile-like
1365:
1452:"Osteology and taxonomic revision of
7:
1775:Journal of Systematic Palaeontology
1257:
1216:
1154:
1142:
1096:
1066:
1010:
959:
881:
871:
828:
803:
793:
125:Fossil specimen, on display at the
1744:Journal of Vertebrate Paleontology
512:A third specimen, attributable to
326:(meaning "submerged lizard") is a
127:National Museum of Natural Science
14:
707:. It was quickly recognized that
2210:
2209:
2192:
1835:
1815:
1472:10.1111/j.1469-7580.2008.00907.x
679:The slab and counterslab of the
137:
1378:"Discovery of the choristodere
697:Beijing Natural History Museum
575:and other choristoderans were
435:from the Jiufotang Formation.
348:. They lived during the early
1:
1852:with two heads has been found
1787:10.1080/14772019.2020.1749147
1591:10.1016/j.cretres.2022.105451
747:and the smaller, lizard-like
705:Sinohydrosaurus lingyuanensis
448:had 19 neck vertebrae, while
1380:Hyphalosaurus baitaigouensis
509:appear to have been webbed.
2331:Cretaceous reptiles of Asia
1848:A fossil unborn or newborn
1265:Hyphalosaurus lingyuanensis
701:Hyphalosaurus lingyuanensis
637:, shallow-water ecosystem.
567:Another fossil specimen of
244:Hyphalosaurus lingyuanensis
2367:
2351:Prehistoric reptile genera
1386:Journal of Palaeogeography
661:Classification and species
249:Gao, Tang & Wang, 1999
2205:
2190:
2031:
2018:
2014:
1995:
1953:
1940:
1894:
1705:10.1007/s00114-010-0654-2
1399:10.1016/j.jop.2024.05.003
1277:
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672:fossils displayed in the
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298:
261:
254:
238:
231:
226:Gao, Tang & Wang 1999
134:Scientific classification
132:
124:
115:
23:
2341:Cretaceous choristoderes
1606:Acta Geoscientica Sinica
674:Hong Kong Science Museum
404:Size compared to a human
312:Li, Zhang & Li, 1999
907:Ikechosaurus sunailinae
695:and the other from the
396:Description and biology
1644:10.1098/rspb.2009.2035
1534:10.1098/rsbl.2006.0580
767:extinction along with
676:
595:
533:
483:
405:
2303:Paleobiology Database
668:
643:is the most abundant
590:
528:
486:Several specimens of
478:
403:
1844:at Wikimedia Commons
731:a junior synonym of
1823:Paleontology portal
1697:2010NW.....97..423J
1685:Naturwissenschaften
1638:(1685): 1235–1239.
1579:Cretaceous Research
1062:"Allochoristodera"
591:Fossil specimen of
461:first recorded time
425:Jiufotang Formation
378:Jiufotang Formation
340:, belonging to the
1460:Journal of Anatomy
677:
596:
534:
484:
406:
2318:
2317:
2290:Open Tree of Life
2232:Taxon identifiers
2223:
2222:
2201:
2200:
2188:
2187:
2184:
2183:
2106:Khurendukhosaurus
2010:
2009:
2006:
2005:
1991:
1990:
1840:Media related to
1781:(15): 1223–1242.
1356:
1355:
1347:
1346:
1338:
1337:
1329:
1328:
1320:
1319:
1311:
1310:
1302:
1301:
1293:
1292:
1225:Khurendukhosaurus
1203:
1202:
1129:
1128:
1052:
1051:
1043:
1042:
992:
991:
940:Tchoiria klauseni
670:H. baitaigouensis
593:H. baitaigouensis
569:H. baitaigouensis
562:H. baitaigouensis
549:H. baitaigouensis
514:H. lingyuanensis,
450:H. baitaigouensis
441:H. baitaigouensis
433:H. baitaigouensis
421:H. baitaigouensis
417:H. baitaigouensis
415:and thousands of
382:Liaoning Province
370:H. baitaigouensis
319:
318:
313:
292:
284:H. baitaigouensis
276:
227:
2358:
2311:
2310:
2298:
2297:
2285:
2284:
2272:
2271:
2259:
2258:
2257:
2227:
2213:
2212:
2196:
2069:Allochoristodera
2029:
2020:
2016:
1951:
1942:
1935:
1934:
1896:
1881:
1874:
1867:
1858:
1839:
1825:
1820:
1819:
1818:
1807:
1806:
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1759:
1739:
1733:
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1680:
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1623:
1614:
1613:
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1217:
1155:
1143:
1097:
1067:
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960:
882:
872:
829:
804:
794:
685:H. lingyuanensis
619:stay submerged.
531:H. lingyuanensis
492:H. lingyuanensis
481:H. lingyuanensis
457:H. lingyuanensis
446:H. lingyuanensis
437:H. lingyuanensis
429:H. lingyuanensis
413:H. lingyuanensis
366:Yixian Formation
362:H. lingyuanensis
311:
286:
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270:
268:H. lingyuanensis
266:
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225:
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142:
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120:
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40:
31:Early Cretaceous
29:Temporal range:
21:
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2219:
2197:
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2161:Mengshanosaurus
2124:Neochoristodera
2118:
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2002:
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1521:Biology Letters
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1303:
1294:
1204:
1162:L. inexpectatus
1130:
1053:
1044:
993:
876:Neochoristodera
729:Sinohydrosaurus
709:Sinohydrosaurus
691:, one from the
663:
585:
523:
479:Restoration of
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309:Sinohydrosaurus
277:
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2157:
2150:
2143:
2136:
2128:
2126:
2120:
2119:
2117:
2116:
2109:
2102:
2099:Philydrosaurus
2095:
2088:
2081:
2073:
2071:
2065:
2064:
2062:
2061:
2054:
2051:Heishanosaurus
2047:
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2011:
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1830:External links
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1761:
1750:(1): 389–391.
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1691:(4): 423–428.
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1466:(6): 747–768.
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1090:Philydrosaurus
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982:C. albertensis
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837:Heishanosaurus
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659:
584:
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372:from both the
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294:
293:
278:
259:
258:
252:
251:
248:
236:
235:
229:
228:
214:
210:
209:
201:
197:
196:
188:
184:
183:
178:
174:
173:
168:
164:
163:
158:
154:
153:
148:
144:
143:
130:
129:
122:
121:
113:
112:
104:
103:
102:
97:
92:
87:
82:
77:
72:
67:
62:
57:
52:
47:
42:
41:
28:
15:
13:
10:
9:
6:
4:
3:
2:
2363:
2352:
2349:
2347:
2344:
2342:
2339:
2337:
2334:
2332:
2329:
2328:
2326:
2309:
2304:
2300:
2296:
2291:
2287:
2283:
2278:
2274:
2270:
2265:
2261:
2256:
2250:
2246:
2245:
2243:
2241:
2240:Hyphalosaurus
2237:
2233:
2228:
2216:
2208:
2207:
2204:
2195:
2177:
2176:
2172:
2170:
2169:
2168:Simoedosaurus
2165:
2163:
2162:
2158:
2156:
2155:
2151:
2149:
2148:
2144:
2142:
2141:
2137:
2135:
2134:
2133:Champsosaurus
2130:
2129:
2127:
2125:
2121:
2115:
2114:
2113:Lazarussuchus
2110:
2108:
2107:
2103:
2101:
2100:
2096:
2094:
2093:
2092:Monjurosuchus
2089:
2087:
2086:
2082:
2080:
2079:
2078:Hyphalosaurus
2075:
2074:
2072:
2070:
2066:
2060:
2059:
2055:
2053:
2052:
2048:
2046:
2045:
2041:
2039:
2038:
2037:Coeruleodraco
2034:
2033:
2030:
2027:
2025:
2021:
2017:
2013:
2001:
2000:
1994:
1981:
1980:
1979:
1978:
1976:
1974:
1970:
1962:
1958:
1957:
1956:
1955:
1952:
1949:
1947:
1943:
1939:
1931:
1927:
1925:
1921:
1919:
1915:
1913:
1909:
1907:
1903:
1902:
1897:
1893:
1889:
1882:
1877:
1875:
1870:
1868:
1863:
1862:
1859:
1853:
1851:
1850:Hyphalosaurus
1846:
1843:
1842:Hyphalosaurus
1838:
1834:
1833:
1829:
1824:
1813:
1804:
1800:
1796:
1792:
1788:
1784:
1780:
1776:
1772:
1765:
1762:
1757:
1753:
1749:
1745:
1738:
1735:
1730:
1726:
1722:
1718:
1714:
1710:
1706:
1702:
1698:
1694:
1690:
1686:
1679:
1676:
1671:
1667:
1662:
1657:
1653:
1649:
1645:
1641:
1637:
1633:
1629:
1622:
1620:
1616:
1611:
1607:
1600:
1597:
1592:
1588:
1584:
1580:
1576:
1569:
1566:
1561:
1557:
1552:
1547:
1543:
1539:
1535:
1531:
1527:
1523:
1522:
1517:
1510:
1508:
1504:
1499:
1495:
1490:
1485:
1481:
1477:
1473:
1469:
1465:
1461:
1457:
1455:
1454:Hyphalosaurus
1446:
1444:
1442:
1440:
1438:
1436:
1434:
1430:
1426:(1): 111–118.
1425:
1421:
1414:
1412:
1410:
1406:
1400:
1395:
1391:
1387:
1383:
1381:
1372:
1370:
1366:
1359:
1352:
1351:
1343:
1342:
1334:
1333:
1325:
1324:
1316:
1315:
1307:
1306:
1298:
1297:
1289:
1288:
1285:
1284:
1282:
1275:
1274:
1271:
1270:
1267:
1266:
1260:
1259:
1253:
1252:
1249:
1248:
1245:
1243:
1242:Hyphalosaurus
1237:
1236:
1233:
1232:
1229:
1228:
1226:
1219:
1218:
1212:
1211:
1208:
1207:
1199:
1198:
1195:
1194:
1188:
1187:
1184:
1183:
1180:
1178:
1177:Lazarussuchus
1172:
1171:
1168:
1167:
1164:
1163:
1157:
1156:
1150:
1149:
1148:Lazarussuchus
1145:
1144:
1138:
1137:
1134:
1133:
1125:
1124:
1121:
1120:
1114:
1113:
1110:
1109:
1106:
1105:
1099:
1098:
1092:
1091:
1087:
1086:
1083:
1082:
1079:
1078:
1076:
1075:Monjurosuchus
1069:
1068:
1061:
1060:
1057:
1056:
1048:
1047:
1039:
1038:
1035:
1034:
1033:S. dakotensis
1028:
1027:
1024:
1023:
1020:
1019:
1013:
1012:
1006:
1005:
1004:Simoedosaurus
1001:
1000:
997:
996:
988:
987:
984:
983:
977:
976:
973:
972:
969:
968:
962:
961:
955:
954:
953:Champsosaurus
950:
949:
946:
945:
942:
941:
935:
934:
931:
930:
927:
926:
924:
917:
916:
913:
912:
909:
908:
902:
901:
898:
897:
894:
893:
892:pijiagouensis
891:
884:
883:
877:
874:
873:
867:
866:
863:
862:
859:
858:
856:
855:Coeruleodraco
849:
848:
845:
844:
841:
840:
838:
831:
830:
824:
823:
820:
819:
816:
814:
813:
806:
805:
799:
796:
795:
791:
788:
786:
782:
778:
774:
770:
766:
762:
758:
757:
752:
751:
750:Monjurosuchus
746:
745:
744:Champsosaurus
740:
739:Hyphalosaurus
736:
734:
733:Hyphalosaurus
730:
726:
725:Hyphalosaurus
722:
718:
714:
713:Hyphalosaurus
710:
706:
702:
698:
694:
690:
686:
682:
675:
671:
667:
660:
658:
656:
655:
650:
649:Hyphalosaurus
646:
642:
641:Hyphalosaurus
638:
636:
632:
631:Hyphalosaurus
628:
624:
623:Hyphalosaurus
620:
618:
617:Hyphalosaurus
614:
613:Hyphalosaurus
609:
608:Hyphalosaurus
605:
601:
600:Hyphalosaurus
594:
589:
582:
580:
578:
574:
573:Hyphalosaurus
570:
565:
563:
559:
558:ovoviviparity
554:
553:Hyphalosaurus
550:
546:
541:
539:
538:Hyphalosaurus
532:
527:
520:
518:
515:
510:
506:
503:
502:Hyphalosaurus
499:
497:
493:
489:
488:Hyphalosaurus
482:
477:
470:
468:
466:
462:
458:
453:
451:
447:
442:
438:
434:
430:
426:
422:
418:
414:
410:
409:Hyphalosaurus
402:
395:
393:
391:
387:
383:
379:
375:
371:
367:
363:
359:
355:
352:period (late
351:
347:
343:
339:
336:
333:
329:
325:
324:
323:Hyphalosaurus
310:
307:
306:
304:
301:
297:
290:
285:
279:
274:
269:
263:
262:
260:
257:
253:
246:
245:
237:
234:
230:
223:
222:
221:Hyphalosaurus
215:
212:
211:
208:
202:
199:
198:
195:
189:
186:
185:
182:
179:
176:
175:
172:
169:
166:
165:
162:
159:
156:
155:
152:
149:
146:
145:
140:
135:
131:
128:
123:
119:
114:
100:
95:
90:
85:
80:
75:
70:
65:
60:
55:
50:
45:
39:
36:123–120
32:
26:
25:Hyphalosaurus
22:
19:
2346:Yixian fauna
2336:Choristodera
2239:
2173:
2166:
2159:
2154:Liaoxisaurus
2152:
2145:
2140:Ikechosaurus
2138:
2131:
2111:
2104:
2097:
2090:
2083:
2077:
2076:
2056:
2049:
2042:
2035:
2024:Choristodera
1999:Choristodera
1997:
1973:Choristodera
1916:Superclass:
1888:Choristodera
1849:
1778:
1774:
1764:
1747:
1743:
1737:
1688:
1684:
1678:
1635:
1631:
1609:
1605:
1599:
1582:
1578:
1568:
1528:(1): 80–81.
1525:
1519:
1463:
1459:
1453:
1423:
1419:
1389:
1385:
1379:
1279:
1278:
1264:
1263:
1241:
1240:
1223:
1222:
1192:
1191:
1176:
1175:
1161:
1160:
1146:
1119:P. proseilus
1118:
1117:
1104:P. proseilus
1103:
1102:
1088:
1073:
1072:
1032:
1031:
1017:
1016:
1002:
981:
980:
966:
965:
951:
939:
938:
921:
920:
906:
905:
890:Ikechosaurus
888:
887:
853:
852:
835:
834:
810:
809:
798:Choristodera
797:
789:
769:crocodilians
756:Shokawa ikoi
754:
748:
742:
738:
737:
732:
728:
724:
712:
708:
704:
700:
684:
683:specimen of
678:
669:
652:
648:
640:
639:
630:
622:
621:
616:
612:
607:
599:
597:
592:
572:
568:
566:
561:
552:
548:
547:specimen of
542:
537:
535:
530:
521:Reproduction
513:
511:
507:
501:
500:
491:
487:
485:
480:
456:
454:
449:
445:
440:
436:
432:
428:
420:
416:
412:
408:
407:
369:
361:
346:Choristodera
322:
321:
320:
308:
288:
283:
272:
267:
243:
242:
233:Type species
220:
219:
194:Choristodera
24:
18:
2058:Irenosaurus
2044:Cteniogenys
1018:S. lemoinei
812:Cteniogenys
604:plesiosaurs
465:polycephaly
2325:Categories
2147:Kosmodraco
1982:see below↓
1961:Sauropsida
1946:Sauropsida
1928:Subclass:
1924:Sauropsida
1612:: 275–285.
1585:: 105451.
1360:References
1193:L. dvoraki
857:jurassicus
765:Cretaceous
577:viviparous
350:Cretaceous
332:freshwater
1918:Tetrapoda
1904:Kingdom:
1803:219047160
1795:1477-2019
1713:0028-1042
1652:0962-8452
1542:1744-9561
1480:0021-8782
1077:splendens
654:Lycoptera
529:Juvenile
364:from the
356:to early
354:Barremian
157:Kingdom:
151:Eukaryota
2249:Wikidata
2215:Category
2175:Tchoiria
1930:Diapsida
1912:Chordata
1910:Phylum:
1906:Animalia
1721:20179895
1670:20018793
1560:17443971
1498:18510504
967:C. gigas
923:Tchoiria
839:pygmaeus
681:holotype
645:tetrapod
545:holotype
452:had 26.
338:reptiles
300:Synonyms
200:Family:
181:Reptilia
171:Chordata
167:Phylum:
161:Animalia
147:Domain:
2295:4128910
2282:1409324
2269:4823712
2255:Q135218
2085:Shokawa
1922:Class:
1729:8719805
1693:Bibcode
1661:2842823
1551:2373827
1489:2423398
1281:Shokawa
925:namsari
785:Miocene
777:lizards
773:turtles
721:synonym
689:Beijing
583:Ecology
543:In the
342:extinct
335:aquatic
256:Species
213:Genus:
187:Order:
177:Class:
105:↓
2308:104045
1801:
1793:
1727:
1719:
1711:
1668:
1658:
1650:
1558:
1548:
1540:
1496:
1486:
1478:
1227:orlovi
781:snakes
635:swampy
496:scales
459:, the
390:fossil
374:Yixian
358:Aptian
344:order
291:, 2004
289:et al.
275:, 1999
273:et al.
2277:IRMNG
1799:S2CID
1725:S2CID
761:clade
627:lakes
598:Both
386:China
328:genus
2264:GBIF
1959:see
1791:ISSN
1717:PMID
1709:ISSN
1666:PMID
1648:ISSN
1556:PMID
1538:ISSN
1494:PMID
1476:ISSN
1283:ikoi
1244:sp.
1179:sp.
815:sp.
779:and
717:ICZN
711:and
703:and
471:Skin
439:and
376:and
368:and
271:Gao
44:PreꞒ
1783:doi
1752:doi
1701:doi
1656:PMC
1640:doi
1636:277
1587:doi
1583:144
1546:PMC
1530:doi
1484:PMC
1468:doi
1464:212
1394:doi
380:of
330:of
287:Ji
2327::
2305::
2292::
2279::
2266::
2251::
1797:.
1789:.
1779:18
1777:.
1773:.
1748:21
1746:.
1723:.
1715:.
1707:.
1699:.
1689:97
1687:.
1664:.
1654:.
1646:.
1634:.
1630:.
1618:^
1610:25
1608:.
1581:.
1577:.
1554:.
1544:.
1536:.
1524:.
1518:.
1506:^
1492:.
1482:.
1474:.
1462:.
1458:.
1432:^
1424:22
1422:.
1408:^
1390:13
1388:.
1384:.
1368:^
787:.
775:,
771:,
735:.
498:.
467:.
384:,
94:Pg
38:Ma
33:,
1880:e
1873:t
1866:v
1805:.
1785::
1758:.
1754::
1731:.
1703::
1695::
1672:.
1642::
1593:.
1589::
1562:.
1532::
1526:3
1500:.
1470::
1402:.
1396::
281:†
265:†
240:†
217:†
204:†
191:†
99:N
89:K
84:J
79:T
74:P
69:C
64:D
59:S
54:O
49:Ꞓ
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