A new small baurioid therocephalian from the Lower Triassic Jiucaiyuan Formation, Xinjiang, China
Received date: 2024-04-04
Online published: 2024-07-26
Several therocephalian species, mainly represented by cranial material from the late Permian, have been reported from China in recent years. Here we describe a tiny new baurioid therocephalian, Jiucaiyuangnathus confusus gen. et sp. nov., from the Jiucaiyuan Formation, Xinjiang, China. The new taxon is represented by a partial snout with occluded partial lower jaw and two postcranial skeletons. Although juvenile in stage, the new species is diagnosed by the following features: round pit in middle of lateral surface of maxilla; lacrimal contact nasal; fossa for dentary tooth on the posterior end of the premaxilla, lateral to the anterior choana; two small vertical triangular ridges extending dorsally and ventrally on the vomerine anterior portion, and bordering a thin vomerine foramen laterally; anterior projection of the lateral part of the frontal on the nasal; symphyseal region of the dentary projected anteriorly; 5 upper premaxillary teeth, upper and lower canines absent, diastema between the last premaxillary upper incisor and first maxillary tooth present, no diastema separating anterior from posterior dentition in the mandible, 10 maxillary teeth and 12 dentary teeth, posterior postcanine expands mesiodistally, having a main large cusps and tiny anterior and posterior accessory cusps in line; neural arches of the atlas fused by the neural spine, neural spine of the axis projected posteriorly, procoracoid foramen lies between procoracoid and scapula. Features of the dentition resembles those of the small baurioid Ericiolacerta parva from South Africa and Silphedosuchus orenburgensis from Russia. The specimens provide the rare opportunity to know in detail the postcranial skeleton of baurioids.
LIU Jun , Fernando ABDALA . A new small baurioid therocephalian from the Lower Triassic Jiucaiyuan Formation, Xinjiang, China[J]. Vertebrata Palasiatica, 2024 , 62(3) : 201 -224 . DOI: 10.19615/j.cnki.2096-9899.240726
[1] | Abdala F, Rubidge B S, Van den Heever J A, 2008. The oldest therocephalians (Therapsida, Eutheriodontia) and the early diversification of Therapsida. Palaeontology, 51: 1011-1024 |
[2] | Angielczyk K D, Liu J, Sidor C A et al., 2022. The stratigraphic and geographic occurrences of Permo-Triassic tetrapods in the Bogda Mountains, NW China - implications of a new cyclostratigraphic framework and Bayesian age model. J Afr Earth Sci, 195: 104655, https://doi.org/10.1016/j.jafrearsci.2022.104655 |
[3] | Benoit J, Manger P R, Rubidge B S, 2016. Palaeoneurological clues to the evolution of defining mammalian soft tissue traits. Sci Rep, 6: 25604, 10.1038/srep25604 |
[4] | Boonstra L D, 1954. A scaloposaurid from the Tapinocephalus -Zone. Ann Mag Nat Hist, 7: 153-157 |
[5] | Botha-Brink J, Modesto S P, 2007. A mixed-age classed ‘pelycosaur’ aggregation from South Africa: earliest evidence of parental care in amniotes? Proc R Soc B, 274: 2829-2834 |
[6] | Botha-Brink J, Modesto S P, 2011. A new skeleton of the therocephalian synapsid Olivierosuchus parringtoni from the Lower Triassic South African Karoo Basin. Palaeontology, 54: 591-606 |
[7] | Brink A S, 1950. Notes on a second specimen of Homodontosaurus kitchingi . South Afr J Sci, 47: 118-119 |
[8] | Broom R, 1901. On Ictidosuchus primaevus. Trans S Afr Philos Soc, 11: 177-184, 10.1080/21560382.1900.9525964 |
[9] | Broom R, 1911. On some new South African Permian reptiles. Proc Zool Soc Lond, 81: 1073-1082 |
[10] | Broom R, 1938. On a nearly complete therocephalian skeleton. Ann Trans Mus, 19: 257-261 |
[11] | Broom R, 1940. On some new genera and species of fossil reptiles from the Karroo beds of Graaff-Reinet. Ann Trans Mus, 20: 157-192 |
[12] | Broom R, 1948a. The skeleton of a very small therocephalian. Ann Trans Mus, 21: 39-41 |
[13] | Broom R, 1948b. New fossil reptile genera from the Bernard Price collection. Ann Trans Mus, 21: 187-194 |
[14] | Colbert E H, Kitching J W, 1981. Scaloposaurian reptiles from the Triassic of Antarctica. Am Mus Novit, 709: 1-22 |
[15] | Fourie H, Rubidge B S, 2007. The postcranial skeletal anatomy of the therocephalian Regisaurus (Therapsida: Regisauridae) and its utilization for biostratigraphic correlation. Palaeont Afr, 42: 1-16 |
[16] | Gigliotti A, Pusch L, Kammerer C F et al., 2023. Craniomandibular anatomy of the akidnognathid therocephalian Olivierosuchus parringtoni from the Early Triassic of South Africa. Palaeont Afr, 56: 142-170 |
[17] | Goloboff P A, Catalano S, 2016. TNT, version 1.5, with a full implementation of phylogenetic morphometrics. Cladistics, 32: 221-238, doi: 10.1111/cla.12160 |
[18] | Hillenius W J, 2000. Septomaxilla of nonmammalian synapsids: soft-tissue correlates and a new functional interpretation. J Morphol, 245: 29-50 |
[19] | Hopson J A, Barghusen H R, 1986. An analysis of therapsid relationships. In: HottonN III, MacLeanP D, RothJ J et al. eds. The Ecology and Biology of Mammal-like Reptiles. Washington D C: Smithsonian Institution Press. 83-106 |
[20] | Hou L H, 1979. On a new theriodont from Inner Mongolia. Vert PalAsiat, 17: 121-130 |
[21] | Huttenlocker A K, Abdala F, 2015. Revision of the first therocephalian, Theriognathus Owen (Therapsida: Whaitsiidae), and implications for cranial ontogeny and allometry in nonmammaliaform eutheriodonts. J Paleontol, 89: 645-664 |
[22] | Huttenlocker A K, Sidor C A, 2016. The first karenitid (Therapsida, Therocephalia) from the upper Permian of Gondwana and the biogeography of Permo-Triassic therocephalians. J Vert Paleont, 36: e1111897, 10.1080/02724634.2016.1111897 |
[23] | Huttenlocker A K, Botha J, Browning C et al., 2022. A Gulliver Scaloposaurus (Therapsida, Therocephalia) from the Katberg Formation of South Africa and its implication for Lilliput assemblages during the Early Triassic recovery. J Afr Earth Sci, 196, 10.1016/j.jafrearsci.2022.104720 |
[24] | Ivakhnenko M F, 2011. Permian and Triassic Therocephals (Eutherapsida) of Eastern Europe. Paleontol J, 45: 981-1144, 10.1134/s0031030111090012 |
[25] | Jasinoski S C, Abdala F, 2017. Aggregations and parental care in the Early Triassic basal cynodonts Galesaurus planiceps and Thrinaxodon liorhinus . PeerJ, 5: e2875, 10.7717/peerj.2875 |
[26] | Kemp T S, 1978. Stance and gait in the hindlimb of a therocephalian mammal-like reptile. J Zool, 186: 143-161 |
[27] | Kemp T S, 1979. The primitive cynodont Procynosuchus : functional anatomy of the skull and relationships. Philos Trans R Soc Lond B, 285: 73-122 |
[28] | Kemp T S, 1986. The skeleton of a baurioid therocephalian therapsid from the Lower Triassic ( Lystrosaurus Zone) of South Africa. J Vert Paleont, 6: 215-232 |
[29] | Koh T P, 1940. Santaisaurus yuani gen. et sp. nov., ein neues Reptil aus der unteren Trias von China. Bull Geol Surv China, 20: 73-92 |
[30] | Li Y H, 1984. On a new scaloposaurid from Inner Mongolia. Vert PalAsiat, 22: 21-28 |
[31] | Liu J, 2020. New chroniosuchian materials from Xinjiang, China. Vert PalAsiat, 58: 283-292 |
[32] | Liu J, Abdala F, 2017a. Therocephalian (Therapsida) and chroniosuchian (Reptiliomorpha) from the Permo-Triassic transitional Guodikeng Formation of the Dalongkou Section, Jimsar, Xinjiang, China. Vert PalAsiat, 55: 24-40 |
[33] | Liu J, Abdala F, 2017b. The tetrapod fauna of the upper Permian Naobaogou Formation of China: 1. Shiguaignathus wangi gen. et sp. nov., the first akidnognathid therocephalian from China. PeerJ, 5: e4150, 10.7717/peerj.4150 |
[34] | Liu J, Abdala F, 2019. The tetrapod fauna of the upper Permian Naobaogou Formation of China: 3. Jiufengia jiai gen. et sp. nov., a large akidnognathid therocephalian. PeerJ, 7: e6463, 10.7717/peerj.6463 |
[35] | Liu J, Abdala F, 2020. The tetrapod fauna of the upper Permian Naobaogou Formation of China: 5. Caodeyao liuyufengi gen. et sp. nov., a new peculiar therocephalian. PeerJ, 8: e9160, 10.7717/peerj.9160 |
[36] | Liu J, Abdala F, 2022. The emblematic South African therocephalian Euchambersia in China: a new link in the dispersal of late Permian vertebrates across Pangea. Biol Lett, 18: 20220222, 10.1098/rsbl.2022.0222 |
[37] | Liu J, Abdala F, 2023. Late Permian terrestrial faunal connections invigorated: the first whaitsioid therocephalian from China. Palaeont Afr, 56: 111-117 |
[38] | Liu J, Yang W, 2022. A gorgonopsian from the Wuttonggou Formation (Changhsingian, Permian) of Turpan Basin. Xinjiang, China. Palaeoworld, 31(3): 383-388 |
[39] | Liu J, Li J L, Cheng Z W, 2002. The Lystrosaurus fossils from Xinjiang and their bearing on the terrestrial Permian-Triassic boundary. Vert PalAsiat, 40: 267-275 |
[40] | Mendrez C H, 1973. Révision du genre Homodontosaurus Broom 1949 et problème de la survivance des Pélycosaures au Permien supérieur en Afrique australe. C R Acad Sci Paris, 276: 1821-1822 |
[41] | Mendrez C H, 1975. Principales variations du palais chez les thérocéphales Sud-Africains (Pristerosauria et Scaloposauria) au cours du Permien Supérieur et du Trias Inférieur. Colloque Int CNRS, 218: 379-408 |
[42] | Mendrez-Carroll C H, 1979. Nouvelle étude du crâne du type de Scaloposaurus constrictus Owen, 1876, spécimen jeune, Therocephalia, Scaloposauria, Scaloposauridae, de la zone à Cistecephalus (Permian supérieur) d'Afrique australe. Bull Mus Natl Hist Nat C, 3: 155-201 |
[43] | Meng Q, Liu J, Varricchio D J et al., 2004. Parental care in an ornithischian dinosaur. Nature, 431: 145-146, 10.1038/431145a |
[44] | Pusch L C, Kammerer C F, Fr?bisch J, 2024. The origin and evolution of Cynodontia (Synapsida, Therapsida): reassessment of the phylogeny and systematics of the earliest members of this clade using 3D-imaging technologies. Anat Rec, 307: 1634-1730, https://doi.org/10.1002/ar.25394 |
[45] | Sigogneau D, 1963. Note sur une nouvelle espece de Scaloposauridae. Palaeont Afr, 8: 13-37 |
[46] | Sigurdsen T, Huttenlocker A K, Modesto S P et al., 2012. Reassessment of the morphology and paleobiology of the therocephalian Tetracynodon darti (Therapsida), and the phylogenetic relationships of Baurioidea. J Vert Paleont, 32: 1113-1134, 10.1080/02724634.2012.688693 |
[47] | Sun A L, 1963. The Chinese kannemeyerids. Palaeont Sin, New Ser C, 17: 1-109 |
[48] | Sun A L, 1991. A review of Chinese therocephalian reptiles. Vert PalAsiat, 29: 85-94 |
[49] | Sun A L, Hou L H, 1981. Hazhenia , a new genus of Scaloposauria. Acta Palaeont Sin, 20(4): 297-310 |
[50] | Tatarinov L P, 2004. The postcranial skeleton of the Late Permian scaloposaurian Karenites ornamentatus (Reptilia, Theriodontia) from the Kirov Region. Paleontol J, 38: 548-555 |
[51] | van den Heever J A, 1994. The cranial anatomy of the early Therocephalia (Amniota: Therapsida). Ann Univ Stellenbosch, 1994: 1-59 |
[52] | Watson D M S, 1931. On the skeleton of a bauriamorph reptile. Proc Zool Soc Lond, 1931: 1163-1205 |
[53] | Yang W, Wan M, Crowley J L et al., 2021. Paleoenvironmental and paleoclimatic evolution and cyclo- and chrono-stratigraphy of upper permian-Lower Triassic fluvial-lacustrine deposits in Bogda Mountains, NW China - implications for diachronous plant evolution across the Permian-Triassic boundary. Earth Sci Rev, 222: 103741, https://doi.org/10.1016/j.earscirev.2021.103741 |
[54] | Young C C, 1936. On a new Chasmatosaurus from Sinkiang. Bull Geol Surv China, 15: 291-320 |
[55] | Young C C, 1939. Additional Dicynodontia remains from Sinkiang. Bull Geol Surv China, 19: 111-139 |
[56] | Young C C, 1952. On a new therocephalian from Sinkiang, China. Acta Sci Sin, 2: 152-165 |
[57] | Young C C, 1961. On a new cynodont from N.W. Shansi. Vert PalAsiat, 1961(2): 109-113 |
[58] | Young C C, 1963. Additional remains of Chasmatosaurus yuani Young from Sinkiang, China. Vert PalAsiat, 7: 215-222 |
[59] | Young C C, 1973a. The discovery of Prolacertilia in Jimusar, Sinkiang. Vert PalAsiat, 11: 46-48 |
[60] | Young C C, 1973b. Note on the labyrinthodont from the Lystrosaurus Zone in Jimusar, Sinkiang. Vert PalAsiat, 11: 50-51 |
[61] | Young C C, 1974. A new genus of Traversodontidae in Jiyuan, Henan. Vert PalAsiat, 12: 203-211 |
[62] | Yuan P L, Young C C, 1934a. On the discovery of a new dicynodon in Sinkiang. Bull Geol Surv China, 13: 563-573 |
[63] | Yuan P L, Young C C, 1934b. On the occurrence of Lystrosaurus in Sinkiang. Bull Geol Surv China, 13: 575-580 |
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