Late Triassic Research Articles

The Resting Breathing Rate of the Dinosaur Plateosaurus trossingensis via Conservation of Energy

Conservation of energy is one of the foundations of science, and in this paper, we use this principle to estimate the resting breathing rate of the dinosaur Plateosaurus trossingensis (see Fig. 1). Animals produce the energy necessary for life via chemical reactions in which biomolecules (such as glucose) react with oxygen to release CO2, H2O, and energy. The metabolism is determined from the animal’s reported mass growth curve (the mass of the animal as a function of age during its juvenile growth) using a model based on conservation of energy. The metabolism reveals the rate at which oxygen is used by the animal. The efficiency of oxygen extraction is assumed to be the same as observed in modern birds (which have a very efficient “one-way” breathing modality and are direct descendants of dinosaurs). Using the estimated concentration of oxygen in Earth’s atmosphere during the Late Triassic period yields the amount of air that P. trossingensis breathed each minute. Finally, the tidal volume (the volume of air inhaled in each breath) was used to calculate its resting breathing rate. This exercise has been used in introductory and intermediate courses on thermal physics, and the students find it empowering (and fun) to be able to gain this insight into the physiology of a dinosaur.

A Review of the Triassic Caddisflies with a Description of New Species from the Middle–Upper Triassic of Kyrgyzstan

A Review of the Triassic Caddisflies with a Description of New Species from the Middle–Upper Triassic of Kyrgyzstan

Vegetation changes and climate shift during the latest Ladinian to the early Carnian: Palynological evidence from the Yanchang Formation, Ordos Basin, China

The Middle–Late Triassic climates have attracted the attention of paleontological and geological scientists for the Carnian pluvial event in the early Late Triassic. The event is well-documented in the pelagic and epi-continental marine deposits of the Tethys, Gondwana, and Laurasia. However, inland terrestrial deposits are less frequently depicted, with high-resolution palynological biostratigraphy constraints. In this study, we report the palynological records from the YC8-1 and YC7-3 sub-members of the Yunmeng profile in the Ordos Basin, China, where the YC7-3 was dated at 236.0–234.1 Ma. Two palynological assemblages were recognized and named the Lundbladispora watangensis–Taeniaesporites combinatus assemblage and Lundbladispora communis–Discisporites granulus assemblage for the YC8-1 and YC7-3 sub-members, respectively. Their ages were determined to be the latest Ladinian and early Carnian, respectively, for their stratigraphic correlations with the global boundary stratotype section and point (GSSP) of the base of Carnian in Europe and additional co-occurring floras with condonts in the Upper Triassic of South China. The coexistence of Cyathidites minor (Couper, 1953), Dictyophyllidites harrisii (Couper, 1958), Apiculatisporis bulliensis (Helby ex De Jersey, 1972), Aratrisporites xiangxiensis (Li and Shang, 2011), Piceaepollenites omoriciformis (Bolkh.) (Xu and Zhang, 1984), Podocarpidites ornatus (Pocock, 1962), Discisporites granulus (Zhang, 1984), and Classopollis (Pflug, 1953) is equivalent to the Carnian palynostratigraphic criterion reported in the North China palynofloristic realm. Vegetational changes, especially those occurring at the boundary between Ladinian and Carnian, account for approximately 70% of ferns and over 30% of gymnosperms lost. These were discovered and attributed to the strong seasonal arid climate, indicated by the emergence of Cheirolepidiaceae and Pinuspollenites. We thus know that the climate during the latest Ladinian and early Carnian was “hot house” with seasonal aridity. In addition, three strong monsoonal pluvial pulses were signaled by the humidity index of lowland plants. The present study will enable a better understanding the Carnian pluvial event in the Late Triassic inland basin.

Triassic stem caecilian supports dissorophoid origin of living amphibians

Living amphibians (Lissamphibia) include frogs and salamanders (Batrachia) and the limbless worm-like caecilians (Gymnophiona). The estimated Palaeozoic era gymnophionan–batrachian molecular divergence1 suggests a major gap in the record of crown lissamphibians prior to their earliest fossil occurrences in the Triassic period2–6. Recent studies find a monophyletic Batrachia within dissorophoid temnospondyls7–10, but the absence of pre-Jurassic period caecilian fossils11,12 has made their relationships to batrachians and affinities to Palaeozoic tetrapods controversial1,8,13,14. Here we report the geologically oldest stem caecilian—a crown lissamphibian from the Late Triassic epoch of Arizona, USA—extending the caecilian record by around 35 million years. These fossils illuminate the tempo and mode of early caecilian morphological and functional evolution, demonstrating a delayed acquisition of musculoskeletal features associated with fossoriality in living caecilians, including the dual jaw closure mechanism15,16, reduced orbits17 and the tentacular organ18. The provenance of these fossils suggests a Pangaean equatorial origin for caecilians, implying that living caecilian biogeography reflects conserved aspects of caecilian function and physiology19, in combination with vicariance patterns driven by plate tectonics20. These fossils reveal a combination of features that is unique to caecilians alongside features that are shared with batrachian and dissorophoid temnospondyls, providing new and compelling evidence supporting a single origin of living amphibians within dissorophoid temnospondyls.

A new typothoracine aetosaur (Archosauria, Pseudosuchia) from the Upper Triassic of India with insights on biostratigraphy, diversification, and paleobiogeography

ABSTRACT A new typothoracine aetosaur is described based on multiple isolated and articulated left paramedian and lateral osteoderms recovered from the Upper Triassic lower Dharmaram Formation of India. The partial carapace of the new taxon is reconstructed as strongly discoidal based on the curvature of the paramedian osteoderms with the widest one positioned dorsal to the mid-dorsal trunk vertebra. Asymmetric lateral osteoderms with acute flexion are considered as precaudals with the angle of flexion decreasing posteriorly. Phylogenetic analysis recovered the new taxon as deeply nested within the clades Typothoracinae and Paratypothoracini, and a sister taxon to Kocurypelta silvestris. The autapomorphic characters involving paramedian osteoderms dorsal to the trunk vertebrae include dorsal surface ornamented by large, irregular pits surrounding the dorsal eminence and radiating ridges in other areas, straight anterior margin of the anteromedial corner of the anterior bar in dorsal view, and raised or ridged and ornamented posteromedial corner. The current study highlights the significance of the new aetosaur, and the age of the lower Dharamaram Formation is modified here as mid-Norian to Rhaetian based on global correlation with other coeval horizons. The recovery of this taxon marks the first record of Paratypothoracini from high paleolatitudes of the Gondwanan region. The study corroborates the earlier findings of a strong Laurasian faunal influx in India during the Late Triassic suggesting possible land bridges and/or conducive environmental conditions for faunal dispersal. http://zoobank.org/urn:lsid:zoobank.org:pub:FCC37C0E-107F-4B15-9460-4E802B465865

A giant phytosaur (Diapsida, Archosauria) from the Upper Triassic of India with new insights on phytosaur migration, endemism and extinction

AbstractA new Mystriosuchinae phytosaur,Colossosuchus techniensis, is described from the Upper Triassic Tiki Formation of India.Colossosuchusis diagnosed by multiple apomorphies, including a strongly downturned terminal rosette (c. 70°), closely spaced mediolateral band‐like ornamentation on dorsal surface of the nasal, dorsolaterally oriented supratemporal fenestra, ventrolaterally inclined postorbital–squamosal bars depressed below the skull table, dorsally convex parietal–squamosal bar that descends ventrolaterally below the skull roof, dome‐shaped skull in lateral view, prominent neural arch laminae and fossae, three sacral vertebrae, robust proximal end of the tibia, and fibula with high anteroposterior flaring of the distal end. The total body length of the largest individual recovered from the bonebed is estimated to be more than 8 m, suggesting thatColossosuchusis one of the largest phytosaurs known. Phylogenetic analysis nestsColossosuchusand other undescribed specimens from India within Mystriosuchinae. These form a distinct clade and represent the earliest record of endemism among Gondwanan phytosaurs. This clade is recovered as sister taxa to ((Volcanosuchus + Rutiodon) + Leptosuchomorpha), where the depressed supratemporal fenestra first appeared in the phytosaur lineage, a feature previously used to diagnose the derived leptosuchomorphs. Early‐diverging phytosaur diversification may have coincided with the final stages of the Carnian Pluvial Event with their possible migratory routes along the circum‐Tethyan coastline. The lineage continued to evolve mostly through endemic radiations and experienced an extinction event during early Norian, which marked the disappearance of most of the non‐leptosuchomorph taxa. This is attributed to post‐CPE aridification, although more study is required.

A Review of the Triassic Caddisflies with a Description of New Species from the Middle–Upper Triassic of Kyrgyzstan

A review of all Triassic caddisflies is compiled and their stratigraphic and geographical distribution is discussed. New species of the caddisflies of the families Cladochoristidae: Cladochorista curta sp. nov. and Cladochoristella sola sp. nov., and Prorhyacophilidae: Prorhyacophila rara sp. nov. and P. batkenica sp. nov are described from the Dzhayloucho locality in Kyrgyzstan (Middle–Upper Triassic, Madygen Formation).

Jurassic to Lower Cretaceous tectonostratigraphy of the German Central Graben, southern North Sea

Abstract The Central Graben is a Mesozoic sedimentary basin that is significantly influenced by rift and salt tectonics. Its southern part is located in the German and Dutch sectors of the North Sea. Even though studies exist on the tectonic and stratigraphic development of the Danish and Dutch Central Graben, the German Central Graben as an important link is less investigated. We aim to fill this gap and to investigate the sedimentary development from the Latest Triassic to the Early Cretaceous, the relative influence of salt and rift tectonics on subsidence and how our results fit into the existing studies of the Danish and Dutch Central Graben. Knowledge of the development of the graben and its sedimentation is critical for any possible economic use like hydrocarbon exploitation or carbon capture and storage. Therefore, we mapped nine laterally traceable horizons on 2D and 3D reflection seismic data from the Lower Jurassic to the Lower Cretaceous within the German Central Graben and adjacent Danish Salt Dome Province as well as the northern Dutch Central Graben. These horizons include the base horizons of four tectonostratigraphic mega-sequences of the southern Central Graben adopted from the current Dutch tectonostratigraphic concept. Based on the mapping results, we constructed subsidence, thickness and erosion maps of the tectonostratigraphic mega-sequences and their subdivisions. The tectonostratigraphic mega-sequences were then correlated with well logs to determine the lithology. The results show that the structural and stratigraphic architecture of the German Central Graben was consecutively dominated by either subsidence controlled by rifting, salt tectonics or by thermal uplift and subsidence. We suggest that the German Central Graben is divided by a large strike-slip fault zone, the Mid Central Graben Transverse Zone, into a northern part that geologically rather belongs to the Danish and a southern part that rather belongs to the Dutch Central Graben. We discuss how this division and the tectonics influenced the regional lithology.

The Relationship between Fluid Evolution and Hydrocarbon Accumulation and Metallization in the Nanpanjiang-Youjiang Basin: Evidence from Calcite Petrography and Fluid Inclusions

In the process of diagenesis and burial of sedimentary basins, basin fluid activities participate in the process of hydrocarbon accumulation and metal mineralization. Understanding the evolution of basin fluid is of great significance in revealing the related hydrocarbon accumulation and mineralization. Paleo-reservoirs are closely associated with Carlin-type gold deposits in the Nanpanjiang-Youjiang Basin, South China. Calcite, the fluid activity product, is closely related to bitumen and gold-bearing pyrite. By integrating petrographic, cathode luminescence, and fluid inclusion analysis, as well as the relevant chronological results of predecessors, this paper attempts to establish the relationship between fluid evolution, hydrocarbon accumulation, and gold mineralization. Two types of calcite (black/gray and white) developed in the Banqi-Yata-Laizishan area, the Nanpanjiang-Youjiang Basin. Black/gray calcite is symbiotic with bitumen and features dark red colors in cathode luminescence. Many hydrocarbon inclusions developed along with fluid inclusion analysis at low homogenization temperatures (65.7~173.1 °C). Combining the previously reported U-Pb ages (~250–230 Ma) of this kind of calcite with some geochemistry data on the associated reservoir and gold deposit, this calcite records the consecutive hydrocarbon accumulation and Carlin-type gold mineralization from the Late Permian to the Late Triassic periods controlled by Indosinian tectonic movement. The white calcite featuring bright red in cathodoluminescence is symbiotic with gold-bearing pyrite and realgar, and the associated fluid inclusions have high homogenization temperatures (128.2~299.9 °C). Combined with regional tectonic background and isotopic chronology (~140–106 Ma), it seems to record the early Cretaceous Carlin-type gold mineralization controlled by the subduction of the paleo-Pacific plate in the late Yanshanian period.

Mummified Dicroidium (Umkomasiales) leaves and reproductive organs from the Upper Triassic of South Australia

Mummified Dicroidium (Umkomasiales) leaves and reproductive organs from the Upper Triassic of South Australia

Evolution and driving mechanisms of water circulation during the late Paleozoic to early Mesozoic

<p indent="0mm">Water circulation plays a crucial role in the Earth’s systems, linking the atmosphere, hydrosphere, lithosphere, and biosphere. During the Paleozoic-Mesozoic transition, climatic and environmental conditions turned into crises, caused by a sudden and serious global warming, accompanied by the largest known extinction event of all time. Several studies have been conducted to discover the causes of this notable climate change. Nevertheless, the evolution of water circulation processes during the Paleozoic-Mesozoic transition is still unclear. Several lithologic indicators present in paleoclimate records have been described over the last few decades. Based on these data, we defined climate zones and calculated their area values using Thiessen polygons and Geographic Information System technology to visualize climate evolution during the Paleozoic-Mesozoic transition. Results of a few of the climate simulations showed changes in precipitation and the amplitudes of the inter-tropical convergence zone (ITCZ) seasonal migration. The results showed several changes in water circulation during the late Paleozoic to early Mesozoic. (1) The climate zones reconstructed by sedimentary and paleontological records showed a remarkable arid expansion. The distribution area of evaporites began to expand in the Middle to Late Permian and reached a peak in the Early Triassic, returned to Middle-Late Permian levels in the Middle Triassic, and thereafter continued to narrow during the Late Triassic to Early Jurassic. (2) Global precipitation was higher during the Late Carboniferous and Early Jurassic and lower in the Middle to Late Permian and Early Triassic. Such a “V” shape represents considerable swing. (3) The assembly of Pangea might have led to “giant land surface winds” in Pangaea and “trans-equatorial winds” in the Tethys region, resulting in a global “megamonsoon”. (4) Seasonal movements of the ITCZ were located at lower latitudes from the Silurian to Carboniferous and from the Jurassic to the present, while reaching higher latitudes with large seasonal oscillations during the Permian-Triassic. Depending on the timing of events, these major changes in water circulation coincided with the assembly of Pangaea, the Variscan or Hercynian orogeny, the end of the late Paleozoic ice age, major carbon emissions, and global warming. These factors are closely related to the changes in atmospheric and water circulation during the Paleozoic-Mesozoic transition. The assembly of Pangea redistributed water storage and altered atmospheric circulation and the “megamonsoon”, while the elevation reduction of mountains traversing middle Pangea weakened the resistance of north and south winds. These factors promoted the evolution of a “megamonsoon” with strong seasonal swings of the ITCZ, which led to the expansion of arid zones and reduced precipitation during the Middle and Late Permian. Meanwhile, large carbon emissions and dramatic global warming altered the energy transition within global systems, which influenced atmospheric circulation. In addition, transformations of global plant clades affected the carbon budget and altered water circulation. In summary, strong fluctuations in water circulation were present during the Paleozoic-Mesozoic transition, especially as observed through climate zones, precipitation and runoff, the “monsoon”, and ITCZ. These crucial processes reflect the interaction between the lithosphere, atmosphere, hydrosphere, and biosphere. However, we have limited knowledge of the complete process of water circulation because geological records and climate simulations are extremely imprecise for the Paleozoic-Mesozoic transition. Future research could focus on other water circulation processes, such as the evolution of underground water, reserves, and fluxes of lakes, rather than only precipitation and “monsoons”. Moreover, the upgrade and extension of big data platforms and a larger number of climate simulations should be considered in future studies.

Latest Triassic (Sevatian–Rhaetian) reef carbonates from the Northern Calcareous Alps (Austria), their mollusc dwellers, and their fate at the end-Triassic extinction event

A reef-associated mollusc fauna (gastropods and bivalves) and its facies context are described from latest Triassic (Sevatian–Rhaetian) reef carbonates of Austria (Rötelwand reef at Gaissau and Gosaukamm near Hallstatt). The studied carbonates from the Rötelwand reef consist of mollusc-rich rudstones, partly boundstones, which contain branched corals (Cycliphyllia and Retiophylia, Pinacophyllum), whereas coralline sponges are absent. The rich foraminiferid fauna that is associated with the reef builders consists of 11 genera; eight of these genera became extinct until the end of the Rhaetian. Associated with small patch reefs was a rich mollusc fauna with 19 gastropod species and 8 epifaunal bivalve species. The gastropod fauna is dominated by Microschiza rhaetica, Trochotoma praecursor, and the large growing Purpuroidea moosleitneri. Six gastropod species are new to science: Angulomphalus senowbarii sp. nov., Stuorella zapfei sp. nov., Hologyra callosa sp. nov., Microschiza rhaetica sp. nov., Angularia corallina sp. nov., and Purpuroidea moosleitneri sp. nov. Four Triassic gastropod species are placed in other genera (new combinations): Tylotrochus diversicostatus Wolff, 1967 and Eucycloscala epitoniformis Nützel and Senowbari-Daryan, 1999 are placed in Sadkia, Praelittorina sepkoskii Nützel and Erwin, 2004 in Microschiza, and Purpuroidea? minioi Leonardi, 1935 in Angularia Koken, 1892. Reversal of precedence is proposed for Angularia Koken, 1892 (Gastropoda) and Angularia Busk, 1881 (Bryozoa) under ICZN Art. 23.9. Although reefs suffered a catastrophic decline at the end of the Triassic, most of the studied reef-associated bivalve and gastropod genera survived into the Jurassic, indicating a considerable ecological plasticity of these groups. Only 12 out of 47 reef-associated mollusc genera became extinct (25.5%). This observation is at variance with earlier suggestions that taxa that were associated with reefs and carbonate substrata had a significantly higher extinction risk than level-bottom dwellers. However, extinction at the species level appears more severe; only three bivalve species but no gastropod species recorded in this fauna have records from the Jurassic.

Grouping behavior in a Triassic marine apex predator

Marine tetrapods occupy important roles in modern marine ecosystems and often gather in large aggregations driven by patchy prey distribution,1,2 social or reproductive behaviors,3,4 or oceanographic factors.5 Here, we show that similar grouping behaviors evolved in an early marine tetrapod lineage, documented by dozens of specimens of the giant ichthyosaur Shonisaurus in the Luning Formation in West Union Canyon, Nevada, USA.6,7 A concentration of at least seven skeletons closely preserved on a single bedding plane received the bulk of previous attention. However, many more specimens are preserved across ∼106 square meters and ∼200 stratigraphic meters of outcrop representing an estimated >105-6 years. Unlike other marine-tetrapod-rich deposits, this assemblage is essentially monotaxic; other vertebrate fossils are exceptionally scarce. Large individuals are disproportionately abundant, with the exception of multiple neonatal or embryonic specimens, indicating an unusual demographic composition apparently lacking intermediate-sized juveniles or subadults. Combined with geological evidence, our data suggest that dense aggregations of Shonisaurus inhabited this moderately deep, low-diversity, tropical marine environment for millennia during the latest Carnian Stage of the Late Triassic Period (237-227 Ma). Thus, philopatric grouping behavior in marine tetrapods, potentially linked to reproductive activity, has an antiquity of at least 230 million years.

A Triassic tritrophic triad documents an early food-web cascade

Endophytic oviposition behavior, the insertion of eggs into plant tissues, represents a sophisticated reproductive strategy of insects.1 This process is accomplished by employing a specialized egg-laying device, the ovipositor, that effectively protects eggs through plant tissue concealment.2,3 Endophytic oviposition behavior is currently common in many lineages of several major, extant insect orders, principally Odonata (dragonflies and damselflies), Orthoptera (katydids and grasshoppers), Hemiptera (cicadas, aphids, scale insects, whiteflies, leafhoppers, and bugs), Coleoptera (beetles), Lepidoptera (moths), and Hymenoptera (sawflies).3,4 Based on the occurrences of egg insertion damage and associated scar tissue expressed in fossil plant stems and leaves, endophytic ovipositional behavior is presumed to have emerged as early as the Early Pennsylvanian Period.5 However, for impression fossils, egg morphology and surrounding scar tissue can be difficult to discern on plants, often resulting in ovipositional damage that may be assigned to exophytic (eggs laid on plant surfaces) or to endophytic behavior.6,7,8,9 This ambiguity is due to the spatial relationships and histological mingling of ovipositional damage and enveloping scars with adjoining plant-host tissues. Here, we describe body fossils of insect eggs within ginkgophyte leaves from the Upper Triassic of China. Feeding damage from an egg-predatory insect commonly occurs on these eggs, as some eggs bear up to several feeding punctures. We provide exceptional body-fossil evidence for resource use of a host plant by an ovipositing insect and unravel the earliest-known tritrophic cascade of a host plant, an ovipositing insect, and an egg-predatory insect.

Provenance of the Mesozoic Succession of Franz Josef Land (North‐Eastern Barents Sea): Paleogeographic and Tectonic Implications for the High Arctic

AbstractStudy of the Mesozoic succession of Franz Josef Land (FJL) has shed new insights on the stratigraphy and geological history of the neighboring portion of the Arctic. Based on the composition of pebbles and cobbles from Lower Jurassic conglomerates, we suggest that the pre‐Mesozoic stratigraphy of the NE Barents Sea comprises Cambrian metasandstones intruded by Late Paleozoic granites and overlain by Carboniferous–Permian sedimentary deposits. U‐Pb and ZHe ages of detrital zircons from Uppermost Triassic–Lower Cretaceous strata of FJL reveal Precambrian to Early Mesozoic grains. The most abundant Late Paleozoic detrital zircon population suggests the existence of the same in age magmatic events in the provenance area. ZHe ages show Late Triassic (ca. 225 Ma) exhumation of the provenance area. Moreover, the youngest grains of detrital zircons are Middle‐Late Triassic in age pointing that significant uplift of provenance coincides with magmatic activity. Based on these data, we suggest that the provenance area for Triassic–Lower Cretaceous strata of FJL was characterized by a similar geological composition, as well as magmatic and tectonic history, to the Taimyr fold‐and‐thrust belt and Kara terrane. A comparison of detrital zircon data from coeval strata elsewhere in the Arctic realm suggests that this eastern provenance area was actively sourcing sediments right across the Barents Sea Basin, and possibly as far as the Sverdrup basin, during the Latest Triassic–Jurassic. The period of Late Triassic uplift represented a significant tectonic event across the north‐eastern Barents Sea, and likely initiated an increase in sediment supply and a reorganization of pre‐existing sediment transport pathways.

New species of permochoristids (Insecta, Mecoptera) from the late Middle Triassic Tongchuan entomofauna in Shaanxi Province, northwestern China

ABSTRACT Permochoristidae is one of the most diverse mecopteran families in the fossil record, but only a few species have been previously described from China. Herein, we describe and illustrate two new permochoristid species, Mesochorista tongchuanensis sp. nov. and Agetopanorpa sinica sp. nov., from the late Middle Triassic of Yanchang Formation in Shaanxi Province. Mesochorista conjunctiva comb. n. is proposed for Qingochorista conjunctiva. Mesochorista tongchuanensis sp. nov. and Agetopanorpa sinica sp. nov. represent the sparse record of Mesochorista and Agetopanorpa in China, respectively. The new discovery adds to our knowledge of their distribution and palaeodiversity during the Triassic. urn:lsid:zoobank.org:pub:DA7ACCFF-D76E-492D-BB1B-37AC1CA5D264

First representative of the odonatan superfamily Triassolestoidea (Odonatoptera: Parazygoptera) from the Upper Triassic of the Korean Peninsula

Koreatriassothemis elongatus gen. et sp. nov. is the first representative of the odonatan superfamily Triassolestoidea described from the Upper Triassic of the Republic of Korea. Despite close similarities with the genera Pseudotriassothemis and Triassoneura, exact affinities within Triassolestoidea remain uncertain, thus discoveries of more complete triassolestoid fossils are required to resolve relationships. The identification of K. elongatus gen. et sp. nov. shows that Odonatoptera and Triassolestoidea diversity was high during the Late Triassic and is currently underestimated. A ‘Samarura-like’ odonatopteran nymph is also identified from the same Upper Triassic outcrop, and may be referable to K. elongatus gen. et sp. nov. André Nel [anel@mnhn.fr], Institut de Systématique, Évolution, Biodiversité (ISYEB), Muséum national d’Histoire naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles, CP50, 57 rue Cuvier, F-75005 Paris, France; Gi-Soo Nam [nks33@naver.com] Gongju National University of Education, Gongju, Chungcheongnam-do 32553, Republic of Korea; Corentin Jouault [jouaultc0@gmail.com], Institut de Systématique, Évolution, Biodiversité (ISYEB), Muséum national d’Histoire naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles, CP50, 57 rue Cuvier, F-75005 Paris, France, and Université des Rennes, CNRS, Géosciences Rennes, UMR 6118, F-35000, Rennes, France, and CNRS, UMR 5554 Institut des Sciences de l’Évolution de Montpellier, Place Eugène Bataillon, F-34095, Montpellier, France.

The first Geinitziidae (Polyneoptera: Reculida) from the Upper Triassic Amisan Formation of South Korea

Shurabia taewani sp. nov., is the first representative of the reculid family Geinitziidae described from the Upper Triassic of South Korea. The preservation of numerous wing venation characters on this new fossil allows for its placement in the genus Geinitzia and a deep comparison with other genera of Geinitziidae. This discovery suggests that the insect paleofauna of the Amisan Formation is rich and needs to be further investigated. Shurabia taewani sp. nov. differs from the other species currently included in the genus, inter alia, because its vein ScP ends near wing mid-length, its fork of M is at the same level as the fork of R, its RP has five branches, its MA four branches, its MP two branches, and its vein m-cua ‘M5′ originates from the stem of M and ends into CuA.

A new genus of Ipsviciidae (Hemiptera, Cicadomorpha) with a tegminal strigil from the Triassic of Madygen

The family Ipsviciidae, originally described from the Upper Triassic of Australia and considered an offshoot of the Scytinopteridae (Tillyard, 1919), was later variously assigned to Heteroptera, Coleorrhyncha, Fulgoroidea, or Cicadomorpha (Cercopoidea or its own superfamily) by different authors (see Lambkin, 2020). Shcherbakov (1984) placed Ipsviciidae in the Scytinopteroidea and demonstrated that this superfamily is ancestral to Heteroptera (Shcherbakov, 1996). The family comprises several genera known from the Triassic and Lower Jurassic of Australia and Eurasia (Lambkin, 2020). A peculiar monotypic genus of Ipsviciidae with a strigil (stridulatory area) on the underside of the tegmen is described below from the Middle to Upper Triassic (Ladinian–Carnian) of the Madygen Lagerstätte, Central Asia. Such a strigil indicates that the new species possessed a stridulatory device of the forewing-hindleg type, similar to those occurring in the extinct Dysmorphoptilidae (Evans, 1961) and some extant true bugs (see Discussion). Dysmorphoptilids and the new ipsviciid genus may have used these devices to produce alarm signals.

The first Dysmorphoptilidae (Hemiptera: Cicadomorpha) from the Upper Triassic of South Korea

Summary Tennentsia koreana n. sp. is the first representative of the family Dysmorphoptilidae described from the Upper Triassic of South Korea. This discovery extends the distribution of the genus Tennentsia in Asia and suggests that it was broadly distributed during the Triassic. Tennentsia koreana n. sp. differs from the other species currently included in the genus Tennentsia, inter alia, because of its tegmen not (or only slightly) emarginate at CuA, RA1 with a weak anterior branch, RA2 not strongly anteriorly curved, with two well-defined branches, strigil in basal part of costal space with coarse punctation.