2018 in paleontology

Paleontology or palaeontology is the study of prehistoric life forms on Earth through the examination of plant and animal fossils.^[1] This includes the study of body fossils, tracks (ichnites), burrows, cast-off parts, fossilised feces (coprolites), palynomorphs and chemical residues. Because humans have encountered fossils for millennia, paleontology has a long history both before and after becoming formalized as a science. This article records significant discoveries and events related to paleontology that occurred or were published in the year 2018.

Flora[edit]

Plants[edit]

Fungi[edit]

Cnidarians[edit]

Research[edit]

• New three dimensionally phosphatized microfossils of coronate scyphozoan Qinscyphus necopinus, including a new type of fossil embryo, are described from the Cambrian (Fortunian) Kuanchuanpu Formation (China) by Shao et al. (2018), who interpret their findings as indicating that Qinscyphus underwent direct development.^[11]
• A study on the morphology of the conulariid species Carinachites spinatus based on a new specimen collected from the lower Cambrian Kuanchuanpu Formation (China) is published by Han et al. (2018).^[12]
• Revision of stony corals from the Lower Cretaceous (Berriasian) Oehrli Formation (Austria and Switzerland) is published by Baron-Szabo (2018), who compares this fauna with five additional Berriasian coral faunas.^[13]

New taxa[edit]

Arthropods[edit]

Bryozoans[edit]

New taxa[edit]

Brachiopods[edit]

Research[edit]

• Studies on the ontogenetic development of early acrotretoid brachiopods based on well preserved specimens of the earliest Cambrian species Eohadrotreta zhenbaensis and Eohadrotreta? zhujiahensis from the Shuijingtuo Formation (China) are published by Zhang et al. (2018).^[37][38]
• A study on the extinction and origination of members of the order Strophomenida during the Late Ordovician mass extinction is published by Sclafani et al. (2018).^[39]
• A study on the body size of several brachiopod assemblages recorded into the extinction interval prior to the Toarcian turnover, collected from representative localities around the Iberian Massif (Spain and Portugal), is published by García Joral, Baeza-Carratalá & Goy (2018).^[40]

New taxa[edit]

Molluscs[edit]

Echinoderms[edit]

Conodonts[edit]

Research[edit]

• A study testing the proposed models of growth of conodont elements is published by Shirley et al. (2018).^[71]
• A study on the histological sections of Ordovician and Permian conodont dental elements from the Bell Canyon Formation (Texas, United States), Harding Sandstone (Colorado, United States), Ali Bashi Formation (Iran) and Canadian Arctic, examining those fossils for the presence and distribution of soft tissue biomarkers, is published by Terrill, Henderson & Anderson (2018).^[72]
• A study evaluating the δ¹⁸O variation within a species-rich conodont assemblage from the Ordovician (Floian) Factory Cove Member of the Shallow Bay Formation, Cow Head Group (western Newfoundland, Canada), as well as assessing the implications of these data for determining the paleothermometry of ancient oceans and conodont ecologic models, is published by Wheeley et al. (2018).^[73][74][75]
• A study on the body size and diversity of Carnian conodonts from South China and their implications for inferring the biotic and environmental changes during the Carnian Pluvial Event is published by Zhang et al. (2018).^[76]
• A study assessing the similarity of late Paleozoic to Triassic conodont faunas known from the Cache Creek Terrane (Canada) is published by Golding (2018).^[77]
• Reconstruction of the multi-element apparatus of the Middle Triassic conodont from British Columbia (Canada) belonging to the Neogondolella regalis group within the genus Neogondolella is presented by Golding (2018).^[78]
• Reconstruction of the number and arrangement of elements in the apparatus of Hindeodus parvus published by Zhang et al. (2017)^[79] is criticized by Agematsu, Golding & Orchard (2018);^[80] Purnell et al. (2018) defend their original conclusions.^[81]
• A cluster of icriodontid conodonts belonging to the species Caudicriodus woschmidti, providing new information on the apparatus structure of icriodontid conodonts, is described from the Lower Devonian sediments in southern Burgenland (Austria) by Suttner, Kido & Briguglio (2018).^[82]
• A study on the species belonging to the genus Neognathodus, evaluating whether previously defined morphotype groups are reliably distinct from one another, is published by Zimmerman, Johnson & Polly (2018).^[83]

New taxa[edit]

Fish[edit]

Amphibians[edit]

Reptiles[edit]

Synapsids[edit]

Non-mammalian synapsids[edit]

Research[edit]

• A description of the postcranial material referable to the caseid species Ennatosaurus tecton is published by Romano, Brocklehurst & Fröbisch (2018).^[105]
• A study on the anatomy and phylogenetic relationships of Milosaurus mccordi is published by Brocklehurst & Fröbisch (2018).^[106]
• A skull of a juvenile specimen of Anteosaurus magnificus is described from the Permian Abrahamskraal Formation (South Africa) by Kruger, Rubidge & Abdala (2018).^[107]
• A study on the evolution of the trigeminal nerve innervation in anomodonts is published by Benoit et al. (2018).^[108]
• A study on the stable oxygen and carbon isotope compositions of dentine apatite in the teeth of twenty-eight specimens of Diictodon feliceps, and on their implications for inferring the potential role of climate in driving the late Capitanian mass extinction of terrestrial tetrapods, is published by Rey et al. (2018).^[109]
• Description of the anatomy of six new skulls of the dicynodont Abajudon kaayai from the Permian (Guadalupian) lower Madumabisa Mudstone Formation (Zambia) and a study on the phylogenetic relationships of the species is published by Olroyd, Sidor & Angielczyk (2018).^[110]
• A study on the anatomy of the bony labyrinth of the specimens of the dicynodont genus Endothiodon collected from the Permian K5 Formation (Mozambique), comparing it with the closely related genus Niassodon, is published by Araújo et al. (2018).^[111]
• A study on the taphonomic history of a monotypic bonebed composed by several individuals attributable to the dicynodont Dinodontosaurus collected in a classic Middle Triassic locality in Brazil, and on its implications for inferring possible gregarious behaviour in Dinodontosaurus, is published online by Ugalde et al. (2018).^[112]
• Redescription of the dicynodont genus Sangusaurus and a study on its feeding system and phylogenetic relationships is published by Angielczyk, Hancox & Nabavizadeh (2018).^[113]
• Partial hindlimb of a dicynodont nearing the size of Stahleckeria potens is described from the Triassic Lifua Member of the Manda Beds (Tanzania) by Kammerer, Angielczyk & Nesbitt (2018), representing the largest dicynodont postcranial element from the Manda Beds reported so far.^[114]
• Description of plant remains and palynomorphs preserved in the coprolites produced by large dicynodonts from the Triassic Chañares Formation (Argentina), and a study on their implications for inferring the diet of dicynodonts, is published by Perez Loinaze et al. (2018).^[115]
• Tetrapod tracks, probably produced by dicynodonts, are described from the Upper Triassic Vera Formation of the Los Menucos Group (Argentina) by Citton et al. (2018).^[116]
• A study on the age of putative Rhaetian dicynodont from Lipie Śląskie (Poland) is published online by Racki & Lucas (2018), who consider it more likely that this dicynodont was of Norian age.^[117]
• A study on the anatomy of the skull of Cynariops robustus is published by Bendel et al. (2018).^[118]
• A study on rates of enamel development in a range of non-mammalian cynodont species, inferred from incremental markings, is published by O'Meara, Dirks & Martinelli (2018).^[119]
• Description of the morphology of the skull of Cynosaurus suppostus and a study on the phylogenetic relationships of the species is published by van den Brandt & Abdala (2018).^[120]
• Fossils of Cynognathus crateronotus are described for the first time from the Triassic Ntawere Formation (Zambia) and Manda Beds (Tanzania) by Wynd et al. (2018).^[121]
• A study on the postcranial anatomy of a specimen of Diademodon tetragonus recovered from the Upper Omingonde Formation (Namibia) is published by Gaetano, Mocke & Abdala (2018).^[122]
• Partial skull and postcranial skeleton of a member of the species Cricodon metabolus is described from the Triassic Ntawere Formation (Zambia) by Sidor & Hopson (2018), who also study the phylogenetic relationships of members of the family Trirachodontidae.^[123]
• A study on the musculature, posture and range of motion of the forelimb of Massetognathus pascuali is published by Lai, Biewener & Pierce (2018).^[124]
• New specimen of Trucidocynodon riograndensis, almost 20% larger than the holotype specimen, is described from the Carnian of Candelária Sequence (southern Brazil) by Stefanello et al. (2018).^[125]
• Right dentary with teeth of Prozostrodon brasiliensis is described from the Late Triassic of Brazil by Pacheco et al. (2018), representing the second known specimen of this species.^[126]
• Description of the anatomy of the postcranial skeleton of Prozostrodon brasiliensis is published by Guignard, Martinelli & Soares (2018).^[127]
• A study on the limb bone histology and life histories of Prozostrodon brasiliensis, Irajatherium hernandezi, Brasilodon quadrangularis and Brasilitherium riograndensis is published by Botha-Brink, Bento Soares & Martinelli (2018).^[128]
• A study on the origin and relationships of ictidosaurian cynodonts, i.e. tritheledontids and therioherpetids, is published by Bonaparte & Crompton (2018).^[129]
• A large (comprising at least 38 individuals) clutch of well-preserved perinates of Kayentatherium wellesi, found with a presumed maternal skeleton, is described from the Lower Jurassic sediments of the Kayenta Formation (found on lands of the Navajo Nation) by Hoffman & Rowe (2018);^[130] in light of this finding, a new interpretation of earlier records of associations between adult and juvenile cynodonts is proposed by Benoit (2019).^[131]
• Cynodont teeth (representing a brasilodontid and a Riograndia-like form) found in the Triassic locality in Brazil which also yielded the fossils of Sacisaurus agudoensis are described by Marsola et al. (2018).^[132]
• A study on the evolution of the mammalian jaw is published by Lautenschlager et al. (2018), who find no evidence for a concurrent reduction in jaw-joint stress and increase in bite force in key non-mammaliaform taxa in the cynodont–mammaliaform transition.^[133]
• Tetrapod burrows, likely produced by small eucynodonts, are described from the Triassic Chañares Formation (Argentina) by Fiorelli et al. (2018).^[134]
• A study on the morphological diversity of vertebral regions in non-mammalian synapsids, and on its implication for elucidating the evolution of anatomically distinct regions of the mammalian spines, is published by Jones et al. (2018).^[135]
• A study on teeth ontogeny in wide range of extinct synapsid lineages is published by LeBlanc et al. (2018), who interpret their findings as indicating that the ligamentous tooth attachment system is not unique to crown mammals within Synapsida.^[136]

New taxa[edit]

Mammals[edit]

Other animals[edit]

Research[edit]

• A review and synthesis of studies on the timing and environmental context of landmark events in early animal evolution is published by Sperling & Stockey (2018).^[147]
• A study on the phylogenetic relationships of the rangeomorphs, dickinsoniomorphs and erniettomorphs as indicated by what is known of the ontogeny of the rangeomorph Charnia masoni, dickinsoniomorph Dickinsonia costata and erniettomorph Pteridinium simplex is published by Dunn, Liu & Donoghue (2018), who consider at least the rangeomorphs and dickinsoniomorphs to be metazoans.^[148]
• A study on the phylogenetic relationships of the rangeomorphs is published by Dececchi et al. (2018).^[149]
• A study on the size distribution and morphological features of a population of juvenile specimens of Dickinsonia costata from the Crisp Gorge fossil locality in the Flinders Ranges (Australia) is published by Reid, García-Bellido & Gehling (2018).^[150]
• A study on the phylogenetic relationships of Dickinsonia based on data from lipid biomarkers extracted from organically preserved Ediacaran macrofossils is published by Bobrovskiy et al. (2018), who interpret their findings as indicating that Dickinsonia was an animal.^[151]
• A study on the anatomy and phylogenetic relationships of Stromatoveris, based on data from new specimens from the Chengjiang Konservat-Lagerstätte (China), is published by Hoyal Cuthill & Han (2018), who interpret Stromatoveris as a member of early animal group Petalonamae that also included Arborea, Pambikalbae, rangeomorphs, dickinsoniomorphs and erniettomorphs.^[152]
• The first reliable occurrence of abundant penetrative trace fossils, providing trace fossil evidence for Precambrian bilaterians with complex behavioural patterns, is reported from the latest Ediacaran of western Mongolia by Oji et al. (2018).^[153]
• Trace fossils produced by Ediacaran animals which burrowed within sediment are described from the shallow-marine deposits of the Urusis Formation (Nama Group, Namibia) by Buatois et al. (2018), who name a new ichnotaxon Parapsammichnites pretzeliformis.^[154]
• New trace fossils from the Ediacaran Shibantan Member of the upper Dengying Formation (China), including burrows and possible trackways which were probably made by millimeter-sized animals with bilateral appendages, are described by Chen et al. (2018).^[155]
• An aggregation of members of the genus Parvancorina, providing evidence of two size-clusters and bimodal orientation in this taxon, is described from the Ediacara Conservation Park (Australia) by Coutts et al. (2018).^[156]
• New, three-dimensional specimens of Charniodiscus arboreus (Arborea arborea), allowing for a detailed reinterpretation of its functional morphology and taxonomy, are described from the Ediacara Member, Rawnsley Quartzite of South Australia by Laflamme, Gehling & Droser (2018).^[157]
• 3D reconstructions of Cloudina aggregates are presented by Mehra & Maloof (2018).^[158]
• A study on Namacalathus and Cloudina skeletons from the Ediacaran Omkyk Member of the Nama Group (Namibia) is published by Pruss et al. (2018), who interpret their findings as indicating that both organisms originally produced aragonitic skeletons, which later underwent diagenetic conversion to calcite.^[159]
• A study on the substrate growth dynamics, mode of biomineralization and possible affinities of Namapoikia rietoogensis is published by Wood & Penny (2018).^[160]
• A review of evidence for existence of swimming animals during the Neoproterozoic is published by Gold (2018).^[161]
• A study on the age of the Cambrian Chengjiang biota (China) is published by Yang et al. (2018).^[162]
• Description of coprolites from the Cambrian (Drumian) Rockslide Formation (Mackenzie Mountains, Canada) produced by an unknown predator, and a study on their implications for reconstructing the Cambrian food web, is published by Kimmig & Pratt (2018).^[163]
• A study on the nature and biological affinity of the Cambrian taxon Archaeooides is published by Yin et al. (2018), who interpret the fossils of Archaeooides as embryonic remains of animals.^[164]
• Zumberge et al. (2018) report a new fossil sterane biomarker, possessing a rare hydrocarbon skeleton that is uniquely found within extant demosponge taxa, from late Neoproterozoic–Cambrian sedimentary rocks and oils, and interpret this finding as indicating that demosponges, and hence multicellular animals, were prominent in some late Neoproterozoic marine environments at least extending back to the Cryogenian period.^[165]
• Diverse, abundant sponge fossils from the Ordovician–Silurian boundary interval are reported from seven localities in South China by Botting et al. (2018), who produce a model for the distribution and preservation of the sponge fauna.^[166]
• A study on the phylogenetic relationships of extant and fossil demosponges is published by Schuster et al. (2018).^[167]
• An assemblage of animal fossils, including the oldest known pterobranchs, preserved in the form of small carbonaceous fossils is described from the Cambrian Buen Formation (Greenland) by Slater et al. (2018).^[168]
• Description of new morphological features of the Cambrian mobergellan Discinella micans is published by Skovsted & Topper (2018).^[169]
• A study on the interrelationships between the eldonioid Pararotadiscus guizhouensis and associated fossil taxa from the Kaili Biota is published by Zhao et al. (2018).^[170]
• A study on the slab with a dense aggregation of members of the species Banffia constricta recovered from the Cambrian Burgess Shale (Canada) and its implications for life habits of the animal is published by Chambers & Brandt (2018).^[171]
• A study on the morphology and phylogenetic affinities of Yuyuanozoon magnificissimi, based on new specimens, is published by Li et al. (2018).^[172]
• A study on the fossil record of early Paleozoic graptoloids and on the factors influencing rates of diversification within this group is published by Foote et al. (2018).^[173]
• A study on the impact of the long-period astronomical cycles (Milankovitch "grand cycles") associated with Earth's orbital eccentricity and obliquity on the variance in species turnover probability (extinction probability plus speciation probability) in Early Paleozoic graptoloids is published by Crampton et al. (2018).^[174]
• A redescription of the species Malongitubus kuangshanensis from the Cambrian Chengjiang Lagerstätte (China) is published by Hu et al. (2018), who interpret this taxon as a pterobranch.^[175]
• A study on the morphology of the palaeoscolecid worm Palaeoscolex from the Lower Ordovician Fezouata Lagerstätte (Morocco), using computed microtomography and providing new information on the internal anatomy of this animal, is published by Kouraiss et al. (2018).^[176]
• The first occurrence of the tommotiid species Paterimitra pyramidalis from the Xinji Formation (China) is reported by Pan et al. (2018).^[177]
• A study on the temporal distribution of lophotrochozoan skeletal species from the upper Ediacaran to the basal Miaolingian of the Siberian Platform, and on its implications for understanding the evolutionary dynamics of the Cambrian explosion, is published by Zhuravlev & Wood (2018).^[178]
• Eggs of ascaridoid nematodes found in crocodyliform coprolites are described from the Upper Cretaceous Bauru Group (Brazil) by Cardia et al. (2018).^[179]
• A study reinterpreting the putative Cambrian lobopodian Mureropodia apae as a partial isolated appendage of a member of the genus Caryosyntrips, published by Pates & Daley (2017)^[180] is criticized by Gámez Vintaned & Zhuravlev (2018);^[181] Pates, Daley & Ortega-Hernández (2018) defend their original conclusions.^[182]
• A study on the early evolution of stem and crown-arthropods as indicated by Ediacaran and Cambrian body and trace fossils is published by Daley et al. (2018).^[183]
• A study on the evolution of ecdysozoan vision, focusing on the evolution of arthropod multi-opsin vision, as indicated by molecular data and data from fossil record, is published by Fleming et al. (2018).^[184]
• A juvenile specimen of Lyrarapax unguispinus, providing new information on the frontal appendages and feeding mode in this taxon, is described from the Cambrian Chiungchussu Formation (China) by Liu et al. (2018).^[185]
• A study evaluating likely swimming efficiency and maneuverability of Anomalocaris canadensis is published by Sheppard, Rival & Caron (2018).^[186]
• Cambrian animal Pahvantia hastata from the Wheeler Shale (Utah, United States), originally classified as a possible arthropod,^[187] is reinterpreted as a suspension-feeding radiodont by Lerosey-Aubril & Pates (2018).^[188]
• The presence of metameric midgut diverticulae is reported for the first time in the stem-arthropod Fuxianhuia protensa by Ortega-Hernández et al. (2018), who interpret their finding as indicative of a predatory or scavenging ecology of fuxianhuiids.^[189]
• Liu et al. (2018) reinterpret putative remains of the nervous and cardiovascular systems in numerous articulated individuals of Fuxianhuia protensa as more likely to be microbial biofilms that developed following decomposition of the intestine, muscle and other connective tissues.^[190]
• A study on the post-embryonic development of Fuxianhuia protensa is published by Fu et al. (2018).^[191]
• Redescription of the fuxianhuiid Liangwangshania biloba is published by Chen et al. (2018).^[192]
• New specimens of the stem-arthropod species Kerygmachela kierkegaardi, providing new information on the anatomy of this species and on the ancestral condition of the panarthropod brain, are described from the Cambrian Stage 3 of the Buen Formation (Sirius Passet, Greenland) by Park et al. (2018).^[193]
• Fossils of spindle- or conotubular-shaped animals of uncertain phylogenetic placement are described from the Ordovician Martinsburg Formation (Pennsylvania, United States) by Meyer et al. (2018).^[194]
• Evidence of macrofauna living at depths of up to 8 metres below the seabed is reported from the Permian Fort Brown Formation (Karoo Basin, South Africa) by Cobain et al. (2018).^[195]
• A study on the morphology of the hyolithid Paramicrocornus zhenbaensis from the lower Cambrian Shuijingtuo Formation (China) is published by Zhang, Skovsted & Zhang (2018), who report that this species lacked helens, and also report the oldest known hyolith muscle scars preserved on the opercula of this species.^[196]
• A study on the feeding strategies and locomotion of Cambrian hyolithids, based on specimens preserved in coprolites from the Chengjiang biota and associated with a Tuzoia carcass from the Balang Fauna (China), is published by Sun et al. (2018).^[197]
• Digestive tract of a specimen of the hyolith species Circotheca johnstrupi from the Cambrian Læså Formation (Bornholm, Denmark) is described by Berg-Madsen, Valent & Ebbestad (2018).^[198]
• The oldest stromatoporoid–bryozoan reefs reported so far are described from the middle Ordovician Duwibong Formation (South Korea) by Hong et al. (2018).^[199]
• Small bioconstructions formed solely by microconchid tube worms, representing the stratigraphically oldest exclusively metazoan bioconstructions from the earliest Triassic (mid-Induan) strata in East Greenland, are reported by Zatoń et al. (2018).^[200]
• The oldest known evidence of trematode parasitism of bivalves in the form of igloo-shaped traces found on shells of the freshwater bivalve Sphaerium is reported from the Upper Cretaceous Judith River Formation (Montana, United States) by Rogers et al. (2018).^[201]
• A study on the predatory drill holes in Late Cretaceous and Paleogene molluscan and serpulid worm prey from Seymour Island (Antarctica) and their implications for inferring the effects of the Cretaceous–Paleogene extinction event on predator-prey dynamics at this site is published by Harper, Crame & Sogot (2018).^[202]
• A study on burrows from Lower–Middle Triassic successions in South China assigned to the ichnotaxon Rhizocorallium, and on their implications for inferring the course of biotic recovery following the Permian–Triassic extinction event, is published by Feng et al. (2018).^[203]
• A study evaluating how different species of fossil and extant free-living cupuladriid bryozoans responded to the environmental changes in the Southwest Caribbean over the last 6 million years is published by O'Dea et al. (2018).^[204]

New taxa[edit]