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1.
We re-examine the phylogenetic relationships of the family Kneriidae using whole mitogenome sequences across all four kneriid genera including the two recently recognized species of Cromeria (C. nilotica and C. occidentalis), and we provide a timescale to discuss the evolution of the family. The resulting phylogeny supports the monophyly of the family Kneriidae and the monophyly of the genus Cromeria. The two Cromeria species exhibit large genetic divergence (18.2%) that is comparable to those between Grasseichthys gabonensis and each two Cromeria species (16.9 and 19.0%). The three paedomorphic kneriid species (C. occidentalis, C. nilotica and G. gabonensis) do not form a monophyletic group, but the alternative hypothesis in which they are monophyletic cannot be statistically rejected. Two alternative relaxed molecular-clock Bayesian analyses, differing on how we time-calibrated the phylogenetic tree using the fossil record, support a Late Jurassic or Late Cretaceous origin of the African freshwater gonorynchiforms. The early diversification of the family Kneriidae is concomitant with the reductions or loss of several morphological characters that took place in a relatively short time interval of about 12–21 million years either during the Eocene or at the end of the Late Cretaceous.  相似文献   

2.
The only previously known Mesozoic fossils of the chilopod order Geophilomorpha are two species from the Late Jurassic and Late Cretaceous, both known from single specimens that cannot be assigned with precision to a family. Four specimens from the Late Cretaceous (earliest Cenomanian) amber of Burma include three that can be identified as conspecific, described here as Kachinophilus pereirai gen. nov. sp. nov. These specimens preserve greater morphological detail in comparison with other fossil geophilomorphs: the form and fine features of the head, the maxillary complex, the trunk sternites with associated glandular pores and the ultimate pair of legs defend the assignment of the species to the extant family Geophilidae, and most probably to a derived subgroup including well‐known extant genera such as Ribautia Brölemann, 1909. Confocal laser scanning microscopy supplements examination under incident and transmitted light to document details of high taxonomic relevance in the head and the forcipular segment. The modern appearance of this species and its membership among deeply nested extant clades are consistent with molecular estimates that most of the diversity of crown‐group Geophilomorpha originated before the Late Cretaceous.  相似文献   

3.
The first dated phylogeny of the weevil subfamily Cryptorhynchinae is presented within a framework of Curculionoidea. The inferred pattern and timing of weevil family relationships are generally congruent with previous studies, but our data are the first to suggest a highly supported sister-group relationship between Attelabidae and Belidae. Our biogeographical inferences suggest that Cryptorhynchinae s.s. originated in the Late Cretaceous (c. 86 Ma) in South America. Within the ‘Acalles group’ and the ‘Cryptorhynchus group’, several independent dispersal events to the Western Palaearctic via the Nearctic occurred in the Late Cretaceous and Early Paleogene. A second southern route via Antarctica may have facilitated the colonization of Australia in the Late Cretaceous (c. 82 Ma), where a diverse Indo-Australian clade probably emerged c. 73 Ma. In the Early Eocene (c. 50–55 Ma), several clades independently dispersed from Australia to proto-New Guinea, i.e. the tribe Arachnopodini s.l., the ‘Rhynchodes group’ and the genus Trigonopterus. New Zealand was first colonized in the Late Palaeocene (c. 60 Ma). Divergence time estimations and biogeographical reconstructions indicate that the colonization of New Guinea is older than expected from current geological reconstructions of the region.  相似文献   

4.
The very common and species-rich Scleractinian genus Actinastrea (family Actinastraeidae, suborder Archeocaeniina) is revised on the basis of the type material of its type species and additional material from the type locality. A lectotype is designated for the type species. It was discovered that Jurassic to Early Cretaceous corals currently assigned to Actinastrea do not fit into the concept of this genus. These species belong to the genus Stelidioseris, which is also revised on the basis of the type of the type species, including designating a lectotype. These two genera are distinguished by various characteristics: septal external parts are swollen in Actinastrea but not in Stelidioseris, the costae are confluent in Stelidioseris but not in Actinastrea, the coenosteum is granulated in Actinastrea but narrow than in Actinastrea and only with costae in Stelidioseris. Actinastrea is restricted to the Late Cretaceous (Late Turonian—Maastrichtian), whereas Stelidioseris originates in the Jurassic and reaches into the Late Cretaceous, but is less common from the Turonian on.  相似文献   

5.
Three new taxa from Albian, Early Cretaceous assemblages in Gondwana (Australia and Antarctica) and two previously described fossils from the Late Cretaceous and Eocene of North America are attributable to the heterosporous semi-aquatic fern family Marsileaceae. They are assigned to Marsileaceaephyllum, a morphotaxon erected here for sterile remains (whole plants, and isolated leaves and leaflets) of Marsileaceae. The Gondwanan taxa, Marsileaceaephyllum lobatum and Marsileaceaephyllum spp. B-C, have either a cruciform leaflet arrangement or dichotomous and anastomosing venation characteristic of modern Marsileaceae. Two previously established taxa, Marsilea johnhallii and Marsilea sp., which represent sterile Marsileaceae, are also transferred to the new genus (now Marsileaceaephyllum johnhallii and Marsileaceaephyllum sp. A, respectively). Examination of all fossil venation patterns reveals four new venation types not present in extant taxa, suggesting that most fossil Marsileaceae (leaves) are distinct from extant genera, and are likely members of extinct lineages. This is further supported by the absence of modern megaspore types in the Early Cretaceous.  相似文献   

6.
Yo  Khand 《Hydrobiologia》2000,419(1):119-124
The Cretaceous and Tertiary development of Mongolian non-marine ostracod faunas is reviewed. During the Late Cretaceous and Early Palaeogene, representatives of the Cypridoidea were widespread and common, Cytheroidea less so and the Darwinuloidea comparatively rare. The evolutionary history of the subfamily Talicyprideinae is considered, with reference to the genera Talicypridea, Altanicypris, Khandiaand Bogdocypris. It is suggested that the extinct Talicyprideinae were related to the mid-Cretaceous to Recent subfamily Cypridinae (e.g. the genus Cypris), both belonging to the family Cyprididae. It is shown that early representatives of the Cyprididae, one of the most diverse non-marine cypridoidean families today, were present from Early Cretaceous onwards (e.g. Lycopterocypris, Mongolocypris), alongside the dominant Cretaceous cypridoideans, the Cyprideidae (e.g. Cypridea), which became extinct in the Palaeogene.  相似文献   

7.
The Normapolles complex, characterised by its oblate and triaperturate pollen, constitutes an important and diverse element of many Late Cretaceous and Early Cainozoic floras of the Northern Hemisphere. Based on the dispersed pollen record alone it has been difficult to assess systematic affinities, but relationships with Fagales have been proposed. Over the past twenty years several exquisitely preserved Late Cretaceous reproductive structures with Normapolles type pollen in situ have been described. In this study we provide a summary and new information of these floral structures. Further, a new genus, Dahlgrenianthus, is described from the Late Cretaceous of southern Sweden. The genus includes the type species Dahlgrenianthus suecicus, a number of reproductive structures referred to Dahlgrenianthus sp., and Dahlgrenianthus trigonus (Knobloch et Mai) comb. nov. from the Maastrichtian flora of Walbeck, Germany. Dahlgrenianthus comprises small flowers with pentamerous perianth and androecium and a tricarpellate gynoecium. It is distinguished from all other Normapolles floral structures in its hypogynous floral organisation. All Normapolles floral structures described so far are thought to be related to various members of the core Fagales, but the group is obviously not monophyletic. The stratigraphic range of the Normapolles taxa and other fagalean fossils strongly suggests that all major fagalean lineages were present by the Cenomanian or earlier.  相似文献   

8.
A series of cranial remains as well as a few postcranial elements attributed to the basal eusuchian Allodaposuchus precedens are described from Velaux‐La Bastide Neuve, a Late Cretaceous continental locality in southern France. Four skulls of different size represent an ontogenetic series and permit an evaluation of the morphological variability in this species. On this basis, recent proposals that different species of Allodaposuchus inhabited the European archipelago are questioned and A. precedens is recognized from other Late Cretaceous deposits of France and Romania. A dentary bone is described for the first time in A. precedens and provides a basis to reconsider the validity of two taxa, Ischyrochampsa meridionalis and Musturzabalsuchus buffetauti, which are interpreted as possible junior synonyms of Allodaposuchus. These results allow the diversity of Late Cretaceous eusuchians from Europe to be refined and recognize a basal stock known as the Hylaeochampsidae sharing an absence of external mandibular fenestrae. Within this family, Allodaposuchus occupies a basal position relative to Acynodon, Iharkutosuchus and Hylaeochampsa. © 2015 The Linnean Society of London  相似文献   

9.
A second basal hadrosauroid dinosaur, Zuoyunlong huangi gen. et sp. nov., is reported from the early Late Cretaceous Zhumapu Formation in Zuoyun County, Shanxi Province, northern China. Zuoyunlong preserves a partial right ilium and ischium and is unique in having a very short postacetabular process 50% as long as the iliac central plate. Our cladistic analysis recovers Zuoyunlong as the most basal Late Cretaceous hadrosauroid, with a sister taxon relationship with Probactrosaurus from the late Early Cretaceous of Inner Mongolia. Including Zuoyunlong, four Cenomanian basal hadrosauroids have been recorded, and the two taxa in North America (Eolambia and Protohadros) represent the earliest known hadrosauroids outside of Asia. In the light of the proposed phylogenetic topology and biogeographic data, the discovery of Zuoyunlong indicates that the first dispersal of hadrosauroids from Asia to North America probably happened around the boundary between the Early and Late Cretaceous.  相似文献   

10.
The problematic lizard family Changjiangosauridae, representatives of which inhabited Asia in the Early Paleogene, is discussed. Six new species of this group, including Acrodontopsis robustus gen. et sp. nov., Agamimus gracilis gen. et sp. nov., Graminisaurus interruptus gen. et sp. nov., Khaichinsaurus reshetovi gen. et sp. nov., Lavatisaurus elegans gen. et sp. nov., and Lentisaurus giganteus gen. et sp. nov., from the Middle Eocene of the Khaichin Uul 2 locality (southern Gobi, Mongolia) are described. It is shown that Changjiangosauridae are probably related to the Late Cretaceous Isodontosauridae and recent Uromastycidae; independent development of a number of dental features in different lineages of Acrodonta (Iguania) is corroborated.  相似文献   

11.
Abstract: The sauropod dinosaur ‘Bothriospondylus’, originally named on the basis of Late Jurassic remains from England, is demonstrated to be invalid, and the characters used to diagnose it are shown to be obsolescent features which are widespread throughout Sauropoda. Material referred to this genus spans a temporal range from the Middle Jurassic until the early Late Cretaceous and has been described from five different countries, across three continents. These remains represent a wide array of sauropod groups, comprising non‐neosauropod eusauropods, a macronarian, titanosauriforms (including at least one definite brachiosaurid) and a rebbachisaurid. The type material of the Middle Jurassic ‘B. madagascariensis’ represents a derived non‐neosauropod eusauropod and possesses two potential autapomorphies. However, as a result of the fragmentary nature of the material and the uncertainty surrounding its association, a new taxon is not erected. Of the numerous specimens referred to ‘Bothriospondylus’, however, several remains are considered diagnostic: Ornithopsis hulkei (Early Cretaceous, UK), Lapparentosaurus madagascariensis (Middle Jurassic, Madagascar) and Nopcsaspondylus alarconensis (early Late Cretaceous, Argentina). At least three types of sauropod were present in the Bathonian (Middle Jurassic) of north‐west Madagascar, with a basal eusauropod (Archaeodontosaurus), a more derived eusauropod (‘B. madagascariensis’) and a titanosauriform (Lapparentosaurus) all approximately contemporaneous. Palaeocontinental reconstructions suggest that Middle Jurassic Madagascan sauropods would still have been capable of global biotic interchange, and this is perhaps reflected in their diverse assemblage. Re‐evaluation of these Malagasy forms has shed new light on this important time period in sauropod evolution.  相似文献   

12.
Abstract

An assemblage of microfossils consisting of non-marine ostracods (Cypridopsis, Gomphocythere, Zonocypris, Eucypris, and Frambocythere), charophyte gyrogonites (Platychara), molluscs (Viviparus, Valvata, and Lymnaea), and fish remains (mainly Phareodus), is here reported from a new intertrappean locality near the town of Manawar, District Dhar, Madhya Pradesh, Central India. The biotic component recovered suggests a Late Cretaceous (Maastrichtian) age for the intertrappean deposit near Manawar. Paleoenvironmentally, the overall biotic assemblage recovered indicates the presence of a freshwater palustrine/lacustrine depositional system connected to a low energy stream/river. Paleobiogeographically, the known high diversity of ostracod genera, especially Eucypris, Cypridopsis, and Gomphocythere, hints at endemism within the Indian Subcontinent during the Late Cretaceous (Maastrichtian). However, the cosmopolitan distribution of the charophyte genus Platychara in the K-Pg interval across the globe (Africa, Europe, and America) and its absence in the Upper Cretaceous of China and Mongolia is quite intriguing.  相似文献   

13.
Paramesopsocus lu n. gen., n. sp. and Paramesopsocus adibi n. sp. are respectively described from the Early Cretaceous amber of Lebanon and from the Late Jurassic limestone of Karatau (Kazakhstan). They are placed within the suborder Psocomorpha, and in the Mesozoic extinct family Paramesopsocidae n. fam. A cladistic phylogeny for Psocomorpha is given including our fossil taxa. The discovery of these new taxa demonstrates the necessity of a deep cladistic redefinition of the currently admitted major subdivisions of this suborder.  相似文献   

14.

Background

The origin of hadrosaurid dinosaurs is far from clear, mainly due to the paucity of their early Late Cretaceous close relatives. Compared to numerous Early Cretaceous basal hadrosauroids, which are mainly from Eastern Asia, only six early Late Cretaceous (pre-Campanian) basal hadrosauroids have been found: three from Asia and three from North America.

Methodology/Principal Findings

Here we describe a new hadrosauroid dinosaur, Yunganglong datongensis gen. et sp. nov., from the early Late Cretaceous Zhumapu Formation of Shanxi Province in northern China. The new taxon is represented by an associated but disarticulated partial adult skeleton including the caudodorsal part of the skull. Cladistic analysis and comparative studies show that Yunganglong represents one of the most basal Late Cretaceous hadrosauroids and is diagnosed by a unique combination of features in its skull and femur.

Conclusions/Significance

The discovery of Yunganglong adds another record of basal Hadrosauroidea in the early Late Cretaceous, and helps to elucidate the origin and evolution of Hadrosauridae.  相似文献   

15.
Morphological features and the affinities of petrified seed cones of the Taxodiaceae, Cupressaceae, and Sciadopityaceae are reevaluated. TheCunninghamia-like plants are the earliest record of the families.Parataiwania explains the divergence ofTaiwania from aCunninghamia-like ancestral form by loss of ovuliferous scale and sclerenchyma.Sequoia-like allies probably diverged from a Cretaceous transitional plant likeYezosequoia and are most diversified in the Late Cretaceous.Yubaristrobus andArchicupressus suggest monophyly ofTaxodium and its allied genera of the Taxodiaceae and the Cupressaceae. The Cupressaceae may be derived from a taxodiaceous plant with orthotropous seeds, acquiring a reniform arrangement of the vascular bundles of the bract-scale complex, decussate or whorled phyllotaxis, and spherical cones consisting of a small number of bract-scale complexes. The Cretaceous fossils of the Sciadopityaceae suggest the ancient origin of the family.  相似文献   

16.
Abstract

In the past, fossilised dinosaur eggshells have been extensively documented from the Upper Cretaceous Lameta Formation of Central India and as many as nine oospecies are known at present from this formation. Compared to this, only one dinosaur oospecies has been described from the Cretaceous succession of the Cauvery Basin. However, the first fossil egg from India, identified as a chelonian egg, was documented from the Aptian – Albian Karai Formation of the Cauvery Basin in 1957. Following this, a solitary titanosaurid dinosaur egg was described from the Upper Cretaceous (Lower Maastrichtian) Kallankuruchhi Formation, Cauvery Basin in 1996. More recently, we have recovered isolated eggshell fragments from the marine part of the Upper Cretaceous (Late Maastrichtian) Kallamedu Formation. Based on eggshell morphology, microstructure and ultrastructure, these eggshell fragments are assigned to the oospecies Fusioolithus baghensis. The new find from the Cauvery Basin is important from palaeobiogeographic point of view as the oofamily Fusioolithidae is found in the Upper Cretaceous strata of India, France, Argentina and Morocco. Based on the common occurrence of similar oospecies in South America, Africa, Europe and India, a Late Cretaceous palaeobiogeographic connection between India and South America as well as Europe via Africa is suggested.  相似文献   

17.
18.
The Abelisauridae are a family of mainly Cretaceous theropod dinosaurs with a wide distribution across the Gondwanan land masses. Although their presence in Europe was reported twenty-five years ago, it has often been considered as controversial largely because of the incompleteness of the available specimens. We report here the discovery of well-preserved abelisaurid material, including a highly diagnostic braincase, at a Late Cretaceous (late Campanian) locality in the Aix-en-Provence Basin, near the eponym city in south-eastern France. A new abelisaurid taxon is erected, Arcovenator escotae gen. nov., sp. nov., on the basis of cranial and postcranial material. A phylogenetic analysis reveals that the new Abelisauridae from Provence is more closely related to taxa from India and Madagascar than to South American forms. Moreover, Genusaurus, Tarascosaurus and the previous Late Cretaceous discoveries are identified as basal abelisaurids. Contrary to previously proposed palaeobiogeographical models of abelisaurid evolution, the presence of the new taxon in Europe suggests that Europe and Africa may have played a major role in abelisaurid dispersal, which apparently involved crossing marine barriers.  相似文献   

19.
The genus Allodaposuchus is an endemic eusuchian from the Late Cretaceous of Europe. This genus was erected in 1928 by Baron Franz Nopcsa based on Allodaposuchus precedens from the Maastrichtian of Romania. Fragmentary skulls recovered from France and Spain were later referred to A. precedens, but three new species of Allodaposuchus have since been described: A. subjuniperus, A. palustris and A. hulki. A set of remains from Velaux, France, was recently interpreted as an ontogenetic series of A. precedens, prompting the argument that other species referred to Allodaposuchus are synonyms of A. precedens. Here, we review intra- and interspecific variability among allodaposuchids. Diagnostic characters for different allodaposuchids are outside the ranges of variation for modern species. Ontogenetic (intraspecific) variation observed in the allodaposuchid from Velaux is not in conflict with the presence of at least four taxa in the European Archipelago during the Late Cretaceous.  相似文献   

20.
The diversity of Cretaceous gymnosperms from the Alchan Depression in northwestern Primorye is discussed. The pike of gymnosperm diversity is restricted to the middle of the Late Albian, and a sharp decline took place in the terminal Albian. A new species, Dictyozamites serafimae sp. nov., is described.  相似文献   

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