Hybodontiform sharks from Middle Triassic Chang 7 Member of the Ordos Basin,Shaanxi, North China: palaeobiological and palaeoecological significances

The lacustrine ecosystem of the early Ladinian of Chang 7 Member of Yanchang Formation in the Ordos Basin (Shaanxi, North China) was proposed as the earliest known Mesozoic-type, trophically multileveled lacustrine ecosystem after the end-Permian mass extinction (EPME). However, the speculated top predator shark was a mere conjecture from coiled coprolites. Herein, thirty-one shark teeth from the organic-rich mudstones of the Chang 7 Member at the Bawangzhuang section, Tongchuan City, Shaanxi Province, North China are described in detail. Two taxa of hybodontiformes, Hybodus? youngi and Hybodus sp., are identified. Based on new material and a re-examination of original material, the previously described Hybodus youngi is substantially revised by adding several newly recognized anatomical features that include flared lateral cusplets, orthodont crown with a pulp cavity surrounded by numerous dentine tubules and a monognathic heterodonty. The results indicate that at least two different hybodont sharks, associated with Saurichthys of ca. 1 m in total length, occupied the higher trophic levels of the Chang 7 Member’s lacustrine ecosystem. The re-establishment of large predator niches encompassing diverse large predators with multiple dietary habits further supports the full recovery of the lacustrine ecosystem structure 10 Myr after the EPME.     

Shark faunas from the Late Jurassic—Early Cretaceous of northeastern Thailand

A revision of the freshwater shark fauna from the Phu Kradung Formation in NE Thailand allows the recognition of a new species of Acrodus, which represents the youngest occurrence of the genus and confirms its displacement in freshwater environments after the Toarcian. The rest of the shark fauna includes teeth of Hybodus sp., aff. Hybodus sp., hybodontid dermal denticles, Jiaodontus sp., Lonchidion sp. A, Lonchidion sp. B, Heteroptychodus cf. H. kokutensis and dorsal fin spines. The presence of Jaiodontus and of unusual hybodontid dermal denticles suggests a Jurassic age for most of the Phu Kradung Formation, whereas the presence of Heteroptychodus suggests an Early Cretaceous age for the top of the Formation. However, the age of the Phu Kradung Formation is still uncertain, with contradictory signals coming from palynology, detrital zircon thermochronology and vertebrate palaeontology. In any case, it appears that this is the oldest occurrence of the genus Heteroptychodus, and suggests a Thai origin for this genus, which may have replaced Acrodus in the Thai freshwater palaeoecosystems. Together with Acrodus, the presence of Lonchidion sp. A suggests some European affinities for the shark fauna from the Phu Kradung Formation.     

Revision and description of water boatmen from the Middle-Upper Jurassic of Northern and Northeastern China (Insecta: Hemiptera: Heteroptera: Corixidae)

Four adult and immature water boatmen from the Middle Jurassic and uppermost Middle Jurassic or lowermost Upper Jurassic Jiulongshan, Haifanggou and Daohugou formations in the northern and northeastern China are described as Yanliaocorixa chinensis (Lin, 1976), Jiulongshanocorixa genuina gen. et sp. nov., and Daohugocorixa vulcanica gen. et sp. nov., referred to the extinct subfamily Velocorixinae, and Karataviella popovi sp. nov., referred to the extant subfamily Diaprepocorinae. All the forms have previously been identified as one species, Yanliaocorixa chinensis. This species, found only in the Haifanggou Formation, is absent from the Jiulongshan Formation and other sites in China. The systematic position of corixids recorded earlier from the Mesozoic of China is reviewed and reassessed. Assemblages of dominant aquatic insects from various Jurassic nonmarine sedimentary basins in northern and northeastern China are described for the first time. They are entirely different between the Jiulongshan, Haifanggou, and Daohugou formations. The first formation is probably older than the other two.     

Mesozoic Trachypachidae (Insecta: Coleoptera) from China

Abstract: Four well‐preserved beetles, attributed to Eodromeinae within Trachypachidae, are described from the Mesozoic of Inner Mongolia, China. Eodromeus robustus sp. nov., E. daohugouensis sp. nov. and Unda chifengensis sp. nov. are from the Middle Jurassic of Daohugou. The diagnostic characters for the two genera are revised, and all species of these genera are keyed. A new genus and species, Sinodromeus liutiaogouensis gen. nov., sp. nov., is described from the Lower Cretaceous Yixian Formation of Liutiaogou. The current fossil records of Trachypachidae from China are reviewed, and only five species (four described here) can be convincingly attributed to this family. The morphological disparity of Mesozoic Eodromeinae suggests that they evolved a broad spectrum of locomotory lifestyles.     

New fossil mantidflies (Insecta: Neuroptera: Mantispidae) from the Mesozoic of north‐eastern China

Abstract:  Three new genera and four new species of the extinct mantidfly subfamily Mesomantispinae (Insecta: Neuroptera: Mantispidae) are described from the Lower Cretaceous Yixian Formation of Liaoning and the Middle Jurassic Jiulongshan Formation of Inner Mongolia: Archaeodrepanicus nuddsi gen. et sp. nov., A. acutus gen. et sp. nov., Sinomesomantispa microdentata gen. et sp. nov., (Yixian Formation) and Clavifemora rotundata gen. et sp. nov. (Jiulongshan Formation). The specimens described herein represent the first Mesozoic mantidfly compression fossils to have body parts preserved, including the specialized raptorial forelegs articulated to the prothorax anteriorly, an autapomorphy of the family. These new taxa further confirm the placement of the subfamily Mesomantispinae within the family Mantispidae; however, the monophyly of Mesomantispinae has not been confirmed, and it is likely that it will prove to be paraphyletic.     

JURASSIC PALAEONTINJDS FROM KARAMAI,XINJIANG, WlTH A DISCUSSION OF PALAEONTINIDAE (HOMOPTERA:PALAEON-TINIDAE) IN CHINA*

Abstract Three new species of fossil insects described here were collected from the Lower Jurassic Badaowan Formation of Tuzigou, Karamai, Xinjiang of northwestern China and are respectively referred to three genera of Palaeontinidae. They are Fletcheriana jurassica sp. nov., Plachutella exculpta sp. nov., and Pseudocossus strenus sp. nov. Some insects of Palaeontinidae have been in discovered succession in northern China. But it should be pointed out that in classification of some of these insects, there exist many questions, which are discussed here. The geological and geographical distributions of Palaeontinidae in China are reviewed in this paper.     

Honghea xui gen. et sp. nov., the second Earliest Jurassic damsel-dragonfly (Odonata: Campterophlebiidae) from the Junggar Basin,NW China

A new campterophlebiid damsel-dragonfly, Honghea xui gen. et sp. nov., is described from the Lower Jurassic Badaowan Formation of the Junggar Basin, NW China. This is the second Chinese Campterophlebiidae recorded for the earliest Jurassic, reflecting the quick diversification and radiation of the damsel-dragonflies during this period. H. nouveau onghea gen. nov. is closely related to Chinese genera Zygokaratawia and Ctenogampsophlebia, both from the Middle Jurassic of the Daohugou Biota; but differs from these genera in having a larger wing size, RP2 slightly distal of Sn, and a narrower area between IR2 and RP3/4.     

New species of Palaeobolbomyia Kovalev and Ussatchovia Kovalev (Diptera, Brachycera, Rhagionidae) from the Callovian-Oxfordian (Jurassic) Daohugou biota of China: Biostratigraphic and paleoecologic implications

Three new species of fossil snipe flies (Insecta, Diptera, Rhagionidae) from the Daohugou Formation of Chifeng City in Nei Monggol Autonomous Region (= Inner Mongolia), northeastern China are described as Palaeobolbomyia sinica nov. sp., Ussatchovia robusta nov. sp. and Ussatchovia gracilenta nov. sp. They represent the first records of the genera Palaeobolbomyia Kovalev and Ussatchovia Kovalev in China and have implications for stratigraphic correlation of the formations in which they are found. Although the precise age of the Daohugou Formation is currently unresolved, it is most likely Callovian-Oxfordian (latest Middle Jurassic-earliest Late Jurassic) rather than early Middle Jurassic (late Aalenian-early Bajocian) or Early Cretaceous.     

New fossil evidence of the early diversification of scarabs: Alloioscarabaeus cheni (Coleoptera: Scarabaeoidea) from the Middle Jurassic of Inner Mongolia,China

Abstract Scarabaeoidea are known from the Lower Jurassic and may have originated in the Triassic based on fossil evidence and phylogenetic research. However, the early diversification of Scarabaeoidea remains unclear due to the lack of high‐quality fossil evidence. Here we describe an exceptionally well‐preserved new fossil of Scarabaeoidea, Alloioscarabaeus cheni gen. et sp. nov from the Middle Jurassic Jiulongshan Formation of Inner Mongolia, China. Based on a morphometric analysis using 17 landmarks of the hind wing of Alloioscarabaeus and 10 scarabaeoid families, we found that Alloioscarabaeus cheni gen. et sp. nov clearly does not belong to any of the known scarabaeoid families and, consequently, is a new family, Alloioscarabaeidae fam. nov., was erected. The discovery of Alloioscarabaeus brought further evidence for the early diversification of major scarab lineages which could allow more detail in the palaeobiogeography of the Scarabaeoidea and Northeast of China which might be one of the originating places or an important radiation place during the evolution of Scarabaeoidea. Alloioscarabaeidae were very likely not good diggers and might have fed on decaying organic materials. Based on the evidence we have now, we tend to believe that most families and some subfamilies of Scarabaeoidea were present in the Jurassic period.     

Fossil coniferous wood from the Middle Jurassic of Liaoning Province, China

Silicified coniferous wood was collected from the Lanqi Formation (late Middle Jurassic in age) at Shebudaigou Village, Liaoning Province, China. Three taxa are identified, namely Pinoxylon dacotense Knowlton, Xenoxylon phyllocladoides Gothan, and Araucariopitys sp. Based on these new data, and those of other fossil plants reported previously from the same formation, we consider the climate during the deposition of the Lanqi Formation was subtropical, humid and seasonal. In this respect the Lanqi flora differs from the coeval Shimengou and Longmen floras from North China. The Longmen flora was deposited during more humid, subtropical conditions, while the Shimengou Formation indicates that the climate was warm temperate and dry. Our data would suggest that the Late Jurassic climatic pattern was initiated as early as the late Middle Jurassic.     

Snipe flies (Diptera: Rhagionidae) from the Daohugou Formation (Jurassic), Inner Mongolia,and the systematic position of related records in China

Abstract: Four new species referred to three new genera and one known genus of fossil snipe flies (Family Rhagionidae) from the Daohugou Formation of Chifeng City in Inner Mongolia, north‐eastern China, are described as Daohugorhagio elongatus gen. et sp. nov., Parachrysopilus jurassicus gen. et sp. nov., Sinorhagio sinuatus sp. nov. and Trichorhagio gregarius gen. et sp. nov. These taxa represent only a fraction of the rhagionid assemblage in the Daohugou biota. They contribute towards the high diversity and abundance of snipe flies during the latest Middle Jurassic – earliest Late Jurassic. The diagnosis of Sinorhagio K. Zhang, Yang and Ren, 2006 is revised based on the new results. Many genera and species from the Lower Cretaceous of China have been assigned to Rhagionidae. Most of these do not actually belong to this family: specifically Mesorhagiophryne incerta Hong and Wang, 1990, M. robusta Hong and Wang, 1990, Mesostratiomyia laiyangensis Hong and Wang, 1990, Stratiomyopsis robusta Hong and Wang, 1990, Longhuaia orientalis Hong, Wang and Sun, 1992, Basilorhagio venusius Ren, 1995. Pauromyia oresbia Ren, 1998 is transferred to an archisargid genus as Sharasargus oresbius (Ren, 1998) comb. nov.     

湖北秭归盆地中侏罗世泄滩组孢粉组合

本文记录了鄂西秭归盆地东缘泄滩组上部21个属36个种的孢粉植物群,其中包括3个新种,讨论了主要属种组合特征和地层延限,根据中侏罗世孢粉植物群组合在国内外的对比,提出泄滩组上部Cyathidites minor-Classopollis-Callialasporites组合的时代属于中侏罗世,这个组合以桫椤科,掌鳞杉科植物的繁盛,和出现大量Cal-lialasporites母体植物为特点,暗示泄滩组上部形成于炎热而干旱的气候环境。     

Two new species of Paramesosciophilodes (Diptera,Nematocera, Mesosciophilidae) from the Middle Jurassic of China

Two new species, Paramesosciophilodes bellus sp. n. and Paramesosciophilodes rarissima sp. n., from the Jiulongshan Formation at Daohugou Village, Inner Mongolia, China, are described in the extinct family Mesosciophilidae. Altogether seven genera with 21 species of mesosciophilids have been described from the Jurassic of Siberia and Kazakhstan, the Lower Cretaceous of Transbaikalia, and the Middle Jurassic of Inner Mongolia. An emended generic diagnosis of Paramesosciophilodes and a list of known taxa of mesosciophilids are provided.     

Sunosuchus (Archosauria, Crocodyliformes) from the Toutunhe Formation (Middle Jurassic) of the Southern Junggar Basin (Xinjiang, NW-China)

A new specimen of the widespread Middle Jurassic to Lower Cretaceous Asian gonipholidid crocodilian genus Sunosuchus is described on the basis of a partial skeleton from the Upper Toutunhe Formation (Middle Jurassic, ?Bathonian-Callovian) of Liuhonggou, SW of Urumqi, Xinjiang Uygur Autonomous Region, People’s Republic of China. The specimen is represented by a partial mandible, teeth, vertebrae, limb and girdle bones and osteoderms. It can be distinguished from other nominal species of the genus by a unique combination of characters: slightly heterodontous dentition, strongly sculptured posteroventral part of the mandible, short fenestra mandibularis, convex dorsal surface of the retroarticular process, keeled cervical vertebral centra and ventral osteoderms with a distinctive sculpture of wide pits and narrow ridges. The heterodontous dentition is a potential autapomorphy of this form. The new specimen is closest in morphology to material described recently from the Callovian of Kirghisia as Sunosuchus sp. It represents the second Middle Jurassic record of the genus, the first crocodile from the Toutunhe Formation, the first substantial crocodile find from the Mesozoic of the Southern Junggar Basin, and the first Middle Jurassic record of Sunosuchus from China. This extends both the paleobiogeographical distribution of the genus in Asia and its stratigraphic distribution in China considerably.     

The first find of chrysomelids (Insecta: Coleopetra: Chrysomeloidea) from Callovian-Oxfordian Daohugou biota of China

Tarsomegamerus mesozoicus nov. gen., nov. sp., an almost complete specimen of leaf beetle from the Callovian-Oxfordian of Daohugou Formation in Inner Mongolia, China is described. Tarsomegamerus mesozoicus is assigned to the Protoscelinae (Chrysomelidae, Coleoptera). This new leaf beetle represents the first record of chrysomeloids from Mesozoic of China and it extends the geographical distribution of Protoscelinae from central Asia into eastern Asia. This find provides new fossil material for studying the origin and evolution of Chrysomeloidea and by making a stratigraphic correlation of the correlative non-marine sedimentary rocks. Although the age of the Daohugou Formation is debatable it is most likely Callovian-Oxfordian (latest Middle Jurassic-earliest Late Jurassic) rather than early Middle Jurassic (late Aalenian-early Bajocian) or Early Cretaceous.     

Quantitative studies of some Jurassic belemnite assemblages

Belemnite deposits were studied in the Jurassic of Britain and the Bathonian-Callovian of the Aar Massif. Special attention was given to a Middle Callovian Belemnopsis concentration at Brora in Sutherland. Studies of guard size, ontogeny, abundance and orientation suggest that these Belemnopsis had seasonal fluctuations in growth, a low mortality rate compared to living coleoids and were probably deposited in local concentrations, by hybodont sharks. Cylindroteuthis abundance is a better guide to the sedimentation rate, than Belemnopsis.     

New hymenopteran insects (Insecta: Vespida) from the lower or middle Jurassic of India

Hymenopterans Xyelula alexandri Rasnitsyn, sp. nov. (Sepulcidae) and Kotaphialtites frankmortoni Rasnitsyn, gen. et sp. nov. (Ephialtitidae) are described from the Lower or Middle Jurassic Kota Formation, Andhra Pradesh, India. These finds prove a considerable similarity between the Gondwanan and Laurasian hymenopteran faunas during the Jurassic, as well as during the Triassic and Cretaceous.     

中国西北地区下侏罗统三工河组原沫蝉科(昆虫纲:半翅目)一新属种*

本文根据一枚产自中国新疆维吾尔自治区下侏罗统三工河组的昆虫化石标本建立1新属新种——秉氏巨沫蝉(Magnicercopis pingi Zhang, Chen et Zhang, gen. et sp. nov.), 归入已灭绝的半翅目原沫蝉科。本新属的衍征包括: MP脉3分支, 存在横脉im, MP脉分支处于CuA脉分支处的基侧。本文对新属种与中国侏罗纪的原沫蝉科类群, 尤其是Longucercopis xinjiangensis Zhang, Chen et Zhang, 2022进行了详细的翅脉对比: M. pingi盖翅长约为L. xinjiangensis的两倍、MP脉3分支(后者2分支)、MP脉首次分支处位于CuA脉分支处基侧(后者位于CuA脉分支处端侧)、M. pingi具横脉im (后者未见im脉)。这一发现不仅提高了对原沫蝉科多样性的认识, 也丰富了该科的翅脉信息。     

New hybodont shark assemblage from the Early Cretaceous of the Basque-Cantabrian Basin

Hybodont remains from the Early Cretaceous of the Basque-Cantabrian Basin (Cantabric Range) in the North of Spain are described for the first time. This assemblage represents a highly diversified shark fauna adapted to different feeding habits. Isolated remains of six hybodont genera, namely Hybodus, Egertonodus, Planohybodus, Lonchidion, Parvodus, and Lissodus, have been recovered and described from the freshwater Vega de Pas Formation in the locality of Vega de Pas (Cantabria, Northern Spain). Most of these taxa are known from the English Wealden, making the shark fauna of the Vega de Pas 1 site the most similar assemblage to English Wealden shark fauna among any other site known in Europe.     

New Insects (Insecta: Trichoptera,Reculida, Eoblattida) from the Mesozoic of Asia

New caddisflies, reculid and eoblattid insects from the Mesozoic of Asia are described. Caddisflies of the families Philopotamidae (Mesoviatrix paradoxa gen. et sp. nov. and Kempia piotri gen. et sp. nov.) and Polycentropodidae (Polylongevus eskovi gen. et sp. nov.) from the Upper Jurassic–Lower Cretaceous of the Kempendyai locality in Yakutia are described. A short review and comparison of fossil members in these families are provided. New Gryllones insects, Shurabia tanga sp. nov., Sauk batkenicus gen. et sp. nov. from the Sauk Tan’ga locality (Lower Jurassic of Kyrgyzstan), Say kirgizicus gen. et sp. nov. from the Shurab III locality (Reculida: Geinitziidae; Lower or Middle Jurassic of Kyrgyzstan) Griphopteron iya sp. nov. (Eoblattida: Blattogryllidae) from Iya locality (Middle Jurassic of Russia) are described.