Skip to main content Skip to main navigation menu Skip to site footer
Responsive image
Issue: Vol. 4457 No. 3: 9 Aug. 2018
Type: Article
Published: 2018-08-09
DOI: 10.11646/zootaxa.4457.3.1
Page range: 351–378
Abstract views: 263
PDF downloaded: 2

Skull anatomy and phylogenetic assessment of a large specimen of Ecteniniidae (Eucynodontia: Probainognathia) from the Upper Triassic of southern Brazil

Programa de Pós-Graduação em Biodiversidade Animal, Universidade Federal de Santa Maria, 97105-120 Santa Maria, RS, Brazil.
Programa de Pós-Graduação em Biodiversidade Animal, Universidade Federal de Santa Maria, 97105-120 Santa Maria, RS, Brazil.
2Centro de Apoio à Pesquisa Paleontológica da Quarta Colônia, Universidade Federal de Santa Maria, Rua Maximiliano Vizzotto, 598, 97230-000 São João do Polêsine, RS, Brazil.
Instituto y Museo de Ciencias Naturales, Universidad Nacional de San Juan, Av. España, 400 (norte), 5400 San Juan, Argentina.
Centro de Apoio à Pesquisa Paleontológica da Quarta Colônia, Universidade Federal de Santa Maria, Rua Maximiliano Vizzotto, 598, 97230-000 São João do Polêsine, RS, Brazil.
Candelária Sequence. Carnian. Late Triassic. Janner outcrop. Probainognathians. Phylogeny. South America Mammalia

Abstract

Ecteniniidae comprises an endemic radiation of carnivore probainognathian cynodonts from the Late Triassic of South America. Three taxa have been included in this clade: Ecteninion lunensis Martínez et al., 1996 and Diegocanis elegans Martínez et al., 2013 from Argentina, and Trucidocynodon riograndensis Oliveira et al., 2010 from Brazil. Herein, a new specimen (skull and mandible) assigned to T. riograndensis from the Carnian of the Candelária Sequence (Southern Brazil) is described. A phylogenetic analysis recovered the new specimen as the sister taxon of the holotype of T. riograndensis, and both in a trichotomy with E. lunensis and D. elegans, all supporting the monophyly of Ecteniniidae. The new specimen of T. riograndensis is almost 20% larger than its holotype. Therefore, it represents one of the largest specimens of a carnivorous probainognathian from the Late Triassic known to date and contributes to knowledge of size variation in ecteniniids.

References

  1. Abdala, F., Barberena, M.C. & Dornelles, J. (2002) A new species of the traversodontid cynodont Exaeretodon from the Santa Maria Formation (Middle/Late Triassic) of Southern Brazil. Journal of Vertebrate Paleontology, 22, 313–325.
    https://doi.org/10.1671/0272-4634(2002)022[0313:ANSOTT]2.0.CO;2

    Abdala, F. & Giannini, N.P. (2002) Chiniquodontid cynodonts: systematic and morphometric considerations. Palaeontology, 45, 1151–1170.
    https://doi.org/10.1111/1475-4983.00280

    Abdala, F. & Ribeiro, A.M. (2010) Distribution and diversity patterns of Triassic cynodonts (Therapsida, Cynodontia) in Gondwana. Palaeogeography, Palaeoclimatology, Palaeoecology, 286, 202–217.
    https://doi.org/10.1016/j.palaeo.2010.01.011

    Abràmoff, M.D., Magalhães, P.J. & Ram, S.J. (2004) Image processing with ImageJ. Biophotonics, 11, 36–43.

    Barberena, M.C. (1981) Uma nova espécie de Massetognathus (Massetognathus ochagaviae, sp. nov.) da Formação Santa Maria, Triássico do Rio Grande do Sul. Pesquisas, 14, 181–195.

    Bonaparte, J.F. (1980) El primer ictidosaurio (Reptilia—Therapsida) de América del Sur, Chaliminia musteloides, del Triásico Superior de La Rioja, República Argentina. In: 2do Congreso Argentino de Paleontología y Bioestratigrafía y 1ro Congreso Latinoamericano de Paleontología, Actas, Buenos Aires, Argentina, 1, 123–133.

    Bonaparte, J.F., Ferigolo, J. & Ribeiro, A.M. (2001) A primitive Late Triassic “ictidosaur” from Rio Grande do Sul, Brazil. Palaeontology, 44, 623–635.
    https://doi.org/10.1111/1475-4983.00194

    Bonaparte, J.F. & Migale, L.A. (2015) Protomamíferos y Mamíferos Mesozoicos de América del Sur. Museo de Ciencias Naturales Carlos Ameghino, Mercedes, 422 pp.

    Broom, R. (1905) Preliminary notice of some new fossil reptiles collected by Mr. Alfred Brown at Aliwal North, South Africa. Records of the Albany Museum, 1, 269–275.

    Broom, R. (1937) A further contribution to our knowledge of the fossil reptiles of the Karroo. Proceedings of the Zoological Society of London, 107, 299–318.
    https://doi.org/10.1111/j.1469-7998.1937.tb00011.x

    Cabreira, S.F., Schultz, C.L., Bittencourt, J.S., Soares, M.B., Fortier, D.C., Silva, L.R. & Langer, M.C. (2011) New stem-sauropodomorph (Dinosauria, Saurischia) from the Triassic of Brazil. Naturwissenschaften, 98, 1035–1040.
    https://doi.org/10.1007/s00114-011-0858-0

    Ezcurra, M.D., Fiorelli, L.E., Martinelli, A.G., Rocher, S.M., von Baczko, B., Ezpeleta, M., Taborda, J.R.A., Hechenleitner, E.M., Trotteyn, M.J. & Desojo, J.B. (2017) Deep faunistic turnovers preceded the rise of dinosaurs in southwestern Pangaea. Nature Ecology & Evolution, 1, 1–1477.

    Fonseca, M.M. (1999) Caracterização faciológica das Formações Santa Maria (Membro Alemoa) e Caturrita: Interpretação da tipologia de sistemas fluviais. Unpublished M.S. Thesis, Universidade Federal do Rio Grande do Sul, Porto Alegre, 203 pp.

    Fourie, S. (1963) Tooth replacement in the gomphodont cynodont, Diademodon. South African Journal of Science, 59, 211–213.

    Goloboff, P.A., Farris, J.S. & Nixon, K.C. (2008) TNT, a free program for phylogenetic analysis. Cladistics, 24, 774–786.
    https://doi.org/10.1111/j.1096-0031.2008.00217.x

    Hilleniuws, J. (2000) Septomaxilla of nonmammalian synapsids: soft tissue correlates and a new functional interpretation. Journal of Morphology, 245, 29–50.
    https://doi.org/10.1002/1097-4687(200007)245:1<29::AID-JMOR3>3.0.CO;2-B

    Hopson, J.A. (1990) Cladistic analysis of therapsid relationships. Journal of Vertebrate Paleontology, 10, 1–28.

    Hopson, J.A. & Kitching, J.W. (2001) A probainognathian cynodont from South Africa and the phylogeny of nonmammalian cynodonts. Bulletin of the Museum of Comparative Zoology, 156, 5–35.

    Horn, B.L.D., Melo, T.M., Schultz, C.L., Philipp, R.P., Kloss, H.P. & Goldberg, K. (2014) A new third-order sequence stratigraphic framework applied to the Triassic of the Paraná Basin, Rio Grande do Sul, Brazil, based on structural, stratigraphic and paleontological data. Journal of South American Earth Sciences, 55, 123–132.
    https://doi.org/10.1016/j.jsames.2014.07.007

    Huene, F.F. von (1936) Die Fossilien Reptilien des Südamerikanischen Gondwanalands. C.H. Beck’sche Verlag, Münich, 332 pp.

    Huxley, T.H. (1859) Postscript to: On the sandstones of Morayshire (Elgin & c.) containing reptile remains, and their relations to the Old Red Sandstone of that country. Quarterly Journal of the Geological Society of London, 15, 138–152.

    Kemp, T.S. (1982) Mammal-like Reptiles and the Origin of Mammals. Academic Press, London, 363 pp.

    Langer, M.C., Ramezani, J. & Da Rosa, Á.A. (2018) U-Pb age constraints on dinosaur rise from south Brazil. Gondwana Research, 57, 133–140.
    https://doi.org/10.1016/j.gr.2018.01.005

    Langer, M.C., Ribeiro, A.M., Schultz, C.L. & Ferigolo, J. (2007) The continental Tetrapod bearing Triassic of South Brazil. Bulletin of the New Mexico Museum of Natural History and Science, 41, 201–218.

    Liparini, A., Oliveira, T.V., Pretto, F.A., Soares, M.B. & Schultz, C.L. (2013) The lower jaw and dentition of the traversodontid Exaeretodon riograndensis Abdala, Barberena & Dornelles, from the Brazilian Triassic (Santa Maria 2 Sequence, Hyperodapedon Assemblage Zone). Alcheringa, 37, 1–23.
    https://doi.org/10.1080/03115518.2013.752607

    Liu, J. & Olsen, P.E. (2010) The phylogenetic relationships of Eucynodontia (Amniota, Synapsida). Journal of Mammalian Evolution, 17, 151–176.
    https://doi.org/10.1007/s10914-010-9136-8

    Liu, J., Soares, M.B. & Reichel, M. (2008) Massetognathus (Cynodontia, Traversodontidae) from the Santa Maria Formation of Brazil. Revista Brasileira de Paleontologia, 11, 27–36.
    https://doi.org/10.4072/rbp.2008.1.03

    Marsicano, C.A., Irmis, R.B., Mancuso, A.C., Mundil, R. & Chemale, F. (2016) The precise temporal calibration of dinosaur origins. Proceedings of the National Academy of Sciences, 113, 509–513.
    https://doi.org/10.1073/pnas.1512541112

    Martinelli, A.G., Fuente, M. & Abdala, F. (2009) Diademodon tetragonus Seeley, 1894 (Therapsida: Cynodontia) in the Triassic of South America and its biostratigraphic implications. Journal of Vertebrate Paleontology, 29, 852–862.
    https://doi.org/10.1671/039.029.0315

    Martinelli, A.G., Kammerer, C.F., Melo, T.P., Neto, V.D.P., Ribeiro, A.M., Da-Rosa, Á.A., Schultz, C.L. & Soares, M.B. (2017) The African cynodont Aleodon (Cynodontia, Probainognathia) in the Triassic of southern Brazil and its biostratigraphic significance. Plos One, 12 (6), e0177948.
    https://doi.org/10.1371/journal.pone.0177948

    Martinelli, A.G. & Rougier, G.W. (2007) On Chaliminia musteloides (Eucynodontia: Tritheledontidae) from the Late Triassic of Argentina, and a phylogeny of Ictidosauria. Journal of Vertebrate Paleontology, 27, 442–460.
    https://doi.org/10.1671/0272-4634(2007)27[442:OCMETF]2.0.CO;2

    Martinelli, A.G. & Soares, M.B. (2016) Evolution of South American cynodonts. Contribuciones Científicas del Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”, 6, 183–197.

    Martinelli, A.G., Soares, M.B., Rodrigues, P. & Schultz, C.L. (2016a) The oldest ictidosaur cynodont (Therapsida) from the late Carnian of southern Brazil and its implication in probainognathian evolution. In: X Simpósio Brasileiro de Paleontologia de Vertebrados, Rio de Janeiro. Boletim de resumos, 2016, pp. 1–111.

    Martinelli, A.G., Soares, M.B. & Schwanke, C. (2016b) Two new cynodonts (Therapsida) from the Middle-Early Late Triassic of Brazil and comments on South American probainognathians. Plos One, 11 (10), e0162945.
    https://doi.org/10.1371/journal.pone.0162945

    Martínez, R.N., Fernandez, E. & Alcober, O.A. (2011) A new advanced eucynodont (Synapsida, Cynodontia) from the Carnian-Norian Ischigualasto Formation, northwestern Argentina. Ameghiniana, 48, 1–109.

    Martínez, R.N., Fernandez, E. & Alcober, O.A. (2013) A new nonmammaliaform eucynodont from the Carnian-Norian Ischigualasto Formation, northwestern Argentina. Revista Brasileira de Paleontologia, 16, 61–76.
    https://doi.org/10.4072/rbp.2013.1.05

    Martínez, R.N. & Forster, C.A. (1996) The skull of Probelesodon sanjuanensis, sp. nov., from the Late Triassic Ischigualasto Formation of Argentina. Journal of Vertebrate Paleontology, 16, 285–291.

    https://doi.org/10.1080/02724634.1996.10011315

    Martínez, R.N., May, C.L. & Forster, C.A. (1996) A new carnivorous cynodonts from the Ischigualasto Formation (Late Triassic, Argentina), with comment on eucynodont phylogeny. Journal of Vertebrate Paleontology, 16, 271–284.

    https://doi.org/10.1080/02724634.1996.10011314

    Müller, R.T., Araújo-Junior, H.I., Aires, A.S.S., Roberto-da-Silva, L. & Dias-da-Silva, S. (2015) Biogenic control on the origin of a vertebrate monotypic accumulation from the Late Triassic of Southern Brazil. Geobios, 48, 331–340.

    https://doi.org/10.1016/j.geobios.2015.05.001

    Müller, R.T., Langer, M.C., Aires, A. & Dias-da-Silva, S. (2014) New dinosauriform (Ornithodira, Dinosauromorpha) record from the Late Triassic of Southern Brazil. Paleontological Research, 18, 118–121.
    https://doi.org/10.2517/2014PR012

    Müller, R.T., Langer, M.C., Cabreira, S.F. & Dias-da-Silva, S. (2016) The femoral anatomy of Pampadromaeus barberenai based on a new specimen from the Upper Triassic of Brazil. Historical Biology, 28, 656–665.
    https://doi.org/10.1080/08912963.2015.1004329

    Müller, R.T., Langer, M.C., Pacheco, C.P. & Dias-da-Silva, S. (2017) The role of ontogeny on character polarization in early dinosaurs: a new specimen from the Late Triassic of Southern Brazil and its implications. Historical Biology, 2017, 1–12.
    https://doi.org/10.1080/08912963.2017.1395421

    Oliveira, T.V. & Schultz, C.L. (2007) La predominancia de Exaeretodon Cabrera 1943 en una sección Triásica de Brasil y su probable correlación con el mismo evento en la porción mediana superior de la Formación Ischigualasto (Triásico de Argentina). In: 23rd Jornadas Argentinas de Paleontología de Vertebrados, Programa de Comunicaciones Científicas y Libro de Resumenes. Trelew, Argentina, pp. 1–9.

    Oliveira, T.V., Schultz, C.L. & Soares, M.B. (2007) O esqueleto pós-craniano de Exaeretodon riograndensis Abdala et al. (Cynodontia, Traversodontidae), Triássico do Brasil. Revista Brasileira de Paleontologia, 10, 79–94.
    https://doi.org/10.4072/rbp.2007.2.02

    Oliveira, T.V., Soares, M.B. & Schultz, C.L. (2010) Trucidocynodon riograndensis gen. nov. et sp. nov. (Eucynodontia), a new cynodont from the Brazilian Upper Triassic (Santa Maria Formation). Zootaxa, 2382, 1–71.

    Owen, R. (1861) Palaeontology, or a Systematic Summary of Extinct Animals and their Geological Relationships. Adam and Black, Edinburgh, 463 pp.

    Pretto, F.A., Langer, M.C. & Schultz, C.L. (2015) New dinosaur remains from the Late Triassic of Southern Brazil (Candelária Sequence, Hyperodapedon Assemblage Zone). Alcheringa, 39, 1–10.
    https://doi.org/10.1080/03115518.2015.994114

    Pretto, F.A., Langer, M.C. & Schultz, C.L. (2018) A new dinosaur (Saurischia: Sauropodomorpha) from the Late Triassic of Brazil provides insights on the evolution of sauropodomorph body plan. Zoological Journal of the Linnean Society. [published online]
    https://doi.org/10.1093/zoolinnean/zly028

    Romer, A.S. (1970) The Chañares (Argentina) Triassic reptile fauna. VI. A chiniquodontid cynodont with incipient squamosal-dentary jaw articulation. Breviora, 344, 1–18.

    Schultz, C.L., Scherer, C.M.S. & Barberena, M.C. (2000) Biostratigraphy of Southern Brazilian Middle-Upper Triassic. Revista Brasileira de Geociências, 30, 495–498.
    https://doi.org/10.25249/0375-7536.2000303495498

    Seeley, H.G. (1894) Researches on the structure, organization, and classification of the fossil Reptilia. Part IX, Section 3. On Diademodon. Philosophical Transactions of the Royal Society of London, 185, 1029–1041.
    https://doi.org/10.1098/rstb.1894.0023

    Sidor, C.A. (2003) The naris and palate of Lycaenodon longiceps (Therapsida: Biarmosuchia), with comments on their early evolution in the Therapsida. Journal of Paleontology, 77, 977–984.

    Soares, M.B., Schultz, C.L. & Horn, B.L.D. (2011) New information on Riograndia guaibensis Bonaparte, Ferigolo & Ribeiro, 2001 (Eucynodontia, Tritheledontidae) from the Late Triassic of Southern Brazil: anatomical and biostratigraphic implications. Anais da Academia Brasileira de Ciências, 83, 329–354.
    https://doi.org/10.1590/S0001-37652011000100021

    Zerfass, H., Lavina, E.L., Schultz, C.L., Garcia, A.J.V., Faccini, U.F. & Chemale, F. JR. (2003) Sequence stratigraphy of continental Triassic strata of Southernmost Brazil: a contribution to Southwestern Gondwana palaeogeography and palaeoclimate. Sedimentary Geology, 161, 85–105.
    https://doi.org/10.1016/S0037-0738(02)00397-4

    Zerfass, H., Sander, A. & Flores, A.E. (2007) Agudo, Folha SH.22-V.C.V, escala 1:100.000, Rio Grande do Sul. Serviço Geológico do Brasil (CPRM), Brasília, 97 pp.