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1.
《Palaeoworld》2022,31(1):131-139
The Dawenkou Basin is a Cenozoic terrestrial fault basin in Shandong Province, East China, containing abundant mineral resources, especially gypsum. Recently a borehole was drilled in this basin unearthing the upper and middle members of the Dawenkou Formation. From the upper member, well-preserved ostracodes were discovered, which are entirely non-marine taxa including species of Eucypris, Caspiolla, Candona and Candoniella. Based on the new material, a new species Candona dawenkouensis n. sp. was erected. The ostracode assemblage biostratigraphically indicates an age of middle Eocene to Oligocene of the upper member of the Dawenkou Formation and the strata bearing mineral resources (mainly gypsum) of the middle member of the Dawenkou Formation is likely early Eocene.  相似文献   

2.
Early ontogenetic shells of 25 species of brackish water and freshwater molluscs from the Ottnangian (Lower Miocene) Oncophora Beds (Lower Bavaria, South Germany) and Kirchberg Formation (Upper Bavaria, South Germany) are described for the first time. Taxonomic implications are discussed. The investigated bivalves (Cardiidae and Dreissenidae) were characterised by an indirect development with inclusion of a planktonic veliger stage. Among the gastropods only three species of the genus CtyrokiaSchlickum, 1965 were characterised by veliger larvae, all the other gastropod species were direct developers, which hatched as crawling young. The species Agapilia schlickumi nov. sp. (Neritidae), Nematurella pseudozilchi nov. sp. and Nematurella strauchi nov. sp. (Hydrobiidae) are introduced. Our study revealed the co-occurrence of 10 molluscan species in the Oncophora Basin of Lower Bavaria and the Kirchberg Basin of Upper Bavaria and thus indicates similar oligohaline to mesohaline coastal swamp milieus for both depositional environments. The presence of planktonic larval development in gastropods indicates a connection to the open sea.  相似文献   

3.
The Campanian–lower Eocene sedimentary succession in the Kharga Oasis yields rare cephalopods that have so far received little attention. Eight cephalopod species; six nautiloids and two ammonites, are identified in the study area. The nautiloids are referred to five genera in three families. All nautiloid species are recorded from the Paleocene and Eocene rocks, two of which are described as new, as follows: Cimomia kurkurensis nov. sp. and Deltoidonautilus hassani nov. sp. The two ammonite species are Libycoceras ismaelis (von Zittel, 1884) and Baculites ovatus Say, 1820, representing the families Sphenodiscidae and Baculitidae, respectively. Baculites anceps of Quaas (1902, non Lamarck, 1822) from the Maastrichtian of the Western Desert of Egypt is here assigned to Baculites ovatus. The palaeobiogeography of these species is studied in detail.  相似文献   

4.
Passaloecus microceras n. sp. from baltic amber (upper Eocene) andP. munax n. sp. from amber of Bitterfeld (lower Miocene) are described and their position within the genusPassaloecus Shuckard is discussed.  相似文献   

5.
Crocodylian remains are collected in 39 fossil-bearing localities but only in seven localities specimens with reliable taxonomic attributions, at least to genus level have been collected. Three species have been reported from the early Lutetian Purga di Bolca site: Pristichampsus cf. Pristichampsus rollinati, Asiatosuchus sp., Hassiacosuchus sp. (=Allognathosuchus sp.). The three crocodilians discovered at Purga di Bolca have been reported also from Geiseltal and Messel (Middle Eocene, Germany). Bolca at that time was part of a Tethysian archipelago and no mammals have been found there till now. Crocodilians and turtles clearly arrived from the European mainland across a marine water barrier. Among the other fossiliferous localities of Veneto, very interesting is the Monte Zuello site, of late Middle Eocene age, yielding a longirostrine crocodilian, Megadontosuchus arduini, a tomistomine species. Tomistomines are known in contemporaneous sediments of both Europe and Africa, but the European forms Dollosuchus and Kentisuchus seem the closest taxa. Remains of Oligocene age have been collected in Veneto and Liguria, but the fossils discovered in the second region are teeth or fragmented bones. The fossil crocodilians of Monteviale (Veneto), of Early Oligocene age, have been assigned to two species but they have been recently all identified as Diplocynodon ratelii, known from several European sites of Late Eocene, Oligocene and Miocene age. This species arrived in the Monteviale area from the European mainland across a narrow sea. Several crocodilian fossils of Miocene age are very fragmentary or represented by isolated teeth. In the Middle and Late Miocene of Sardinia, a well-established species, Tomistoma calaritanum is present. Remains of Tomistoma of the same age have been reported in some localities in Tuscany, Apulia, Sicily and Malta. In the Mediterranean area, the genus is known from European and African sites (of older age). The colonisation of Europe by this genus is the result of a dispersion from Africa (or less probably from Asia). During Late Miocene Sardinia and Tuscany belong to the same palaeobioprovince characterized by the Oreopithecus-Maremmia fauna. In Tuscany, a crocodilian identified as Crocodylus bambolii is present in the late Miocene site of Monte Bamboli. If the generic attribution of this form is correct, its ancestors must have arrived from Africa. Another fossil assemblage of Late Miocene age characterizes the Apulia-Abruzzi palaeobioprovince (Hoplitomeryx-Microtia fauna) and testifies complete isolation between the two palaeobioprovinces. In this last area, remains of Crocodylus sp. have been collected in coastal sandstones at Scontrone (Abruzzi) and in several fissure fillings of Gargano of slightly younger age. The ancestors of this species arrived from Africa while no African elements are present among the mammalian fauna. The dispersion of the genus Crocodylus in the Italian palaeoislands may have taken place once, with allopatric differentiation of the two populations (Tuscany-Sardinia and Apulia-Abruzzi) or twice with independent colonisation of each area.  相似文献   

6.
The Middle Miocene sediments of Maboko Island (Lake Victoria) in western Kenya yielded numerous avian bones, which remained, however, little studied. The significance of this material is shown by the recent identification of an opisthocomiform bird. In the present study, further avian remains from Maboko Island are described. Most of the specimens belong to aquatic or semi-aquatic groups, of which some are closely related to taxa known from Early and Middle Miocene European avifaunas, that is, Nectornis cormorants (N. africanus nov. sp.) and Laricola-like Laromorphae. The fossil material also includes Ciconiidae (cf. Ciconia), Pelecanidae, Phoenicopteridae (Leakeyornis aethiopicus), Musophagidae, and a species of Ardeidae, which closely resembles the taxon Pikaihao from the Early Miocene of New Zealand. Some avian remains from Maboko Island belong to higher-level taxa unknown from the Middle Miocene of Europe. The occurrence of a giant Jacanidae (?Nupharanassa mabokoensis nov. sp.) is of particular interest, because these are globally absent in extant avifaunas and were previously only known from the Late Eocene/Early Oligocene of Egypt. Further unknown from contemporaneous European sites are small representatives of Jacanidae, Bucerotidae, and Alcedinidae, with the fossils of the latter two taxa being among the earliest published records of their respective groups. Several of the taxa that are common in contemporaneous European avifaunas have not been found in Maboko, and in spite of less pronounced climatic differences, Middle Miocene Afrotropical avifaunas already appear to have been distinct from contemporaneous European ones.  相似文献   

7.
8.
Four decapod crustacean species from the Middle Miocene Mishan Formation of Hormozgan Province, Southern Iran are described. Three species of leucosiid crabs represent the first fossil record for their respective genera outside the Indo-Pacific region. The oldest records for Leucosia sensu lato, Phylira sensu lato, and Arcania are from Middle Miocene deposits of the Indo-Pacific, and thus their paleobiogeographic distribution is extended for this lapse of time. Harpactocarcinus miocenicus n. sp. represents the youngest and most oriental occurrence for a typically Eocene genus, whose species are known mainly from Central Europe. This contribution represents the first formal report for Tertiary crustaceans from Iran.  相似文献   

9.
New taxa of Orthoptera Ensifera are described in the families Mogoplistidae [Protomogoplistes asquamosus gen. et sp. nov. (Upper Cretaceous) in the subfamily Protomogoplistinae subfam. nov. and Archornebius balticus gen. et sp. nov. (Eocene), Pseudarachnocephalus gen. nov., P. dominicanus sp. nov., and P. latiusculus sp. nov. (all Miocene) in Mogoplistinae] and Gryllidae [Eopentacentrus borealis gen. et sp. nov. (Eocene), ?Grossoxipha feminea sp. nov. (Miocene), and Apentacentrus copalicus sp. nov. in the subfamily Pentacentrinae, ?Cyrtoxipha electrina sp. nov. and ?Cyrtoxipha illegibilis sp. nov. (both Miocene) in Trigonidiinae, and Baltonemobius fossilis gen. et sp. nov. (Eocene) in Nemobiinae]. The Miocene genera Proanaxipha Vickery et Poinar and Grossoxipha Vickery et Poinar are transferred from the subfamily Trigonidiinae to Pentacentrinae. P. latoca Vickery et Poinar and Abanaxipha longispina Vickery et Poinar are redescribed; the male of the latter species is described for the first time.  相似文献   

10.
《Palaeoworld》2023,32(3):523-546
The stratigraphic correlation of the Kuma Formation from the south of the Russian Platform and the Crimea-Caucasian region has been a matter of debate for decades. A bed-by-beds study of dinocysts and nannoplankton from the the Kuma Formation made it possible to recognize a sequence of biotic events, important for defining and correlating the biozones. At the Bakhchisarai limestone quarry, six dinoflagellate zones and six nannoplankton zonal units were recognized, assignable to the Middle Eocene Lutetian and Bartonian stages. Our paleoecological analyses of the organic-walled microphytoplankton assemblages and of the palynofacies indicate that the the Kuma Formation deposited in the inner shelf zone, probably of anoxic and eutrophic settings within the Pontic-Transcaucasian magmatic belt. Assemblages of organic-walled microphytoplankton comprise potentially toxic dinoflagellate species of Alexandrium. The Middle Eocene Climatic Optimum event is recorded in the upper part of the the Kuma Formation, presumably indicated by the Dracodinium rhomboideum dinoflagellate zone, which is characterized by an acme of Dracodinium laszczynskii Gedl and the lowest occurrence of nannofossils Reticulofenestra bisecta (Hay, Mohler and Wade) Roth. Two new species are described: Pentadinium rugosum Vasilyeva, n. sp. (dinocyst) and Corannulus tauricum Musatov, n. sp. (nannofossil). The bioevents and biozones established herein are significant for correlations of the Middle Eocene of the Crimean Peninsula and the south of the Russian Platform.  相似文献   

11.
《Palaeoworld》2021,30(4):746-756
A new fossil species, Cedrus anatolica n. sp., is described from the early Miocene Hançili Formation of Turkey. All analyses were performed on the thin sections housed at Istanbul University – Cerrahpasa. The new species was interpreted as having the closest affinity with the modern Mediterranean species Cedrus atlantica (Endlicher) Manetti ex Carriere and Cedrus libani Richard. The evolutionary line shows some changes in wood anatomy. From the early Cretaceous to the early Miocene, the pits on the tangential walls of the tracheids gradually decreased, the height of rays increased and the number of epithelial cells in the traumatic resin canals increased slightly. These features are similar in three modern species; other wood anatomical features are also quite stable among the new fossil and modern species.  相似文献   

12.
《Annales de Paléontologie》2017,103(2):141-147
A small bird with a shorebird-like beak and a very long hind toe is described from the Early Eocene of Messel in Germany. Vanolimicola longihallucis, gen. et sp. nov. is one of the few candidate species for a “wading bird” from Messel, that is, a bird that may have foraged along the shoreline of the ancient lake. A few features indicate a relationship to charadriiform birds and Jacanidae (jacanas) in particular, but charadriiform affinities are only weakly supported. In the preserved skeletal elements, V. longihallucis also resembles the taxon Songzia from the Early Eocene of China, which is considered to be a representative of the Ralloidea (rails and allies). A potential biogeographic significance of the new Messel fossil is strengthened by similar fossils from the North American Green River Formation.  相似文献   

13.
Ant imprints, new and previously known, from Middle Miocene deposits near Kerch (Crimean Peninsula, Russia) are described or redescribed. A new Myrmicinae species, Solenopsis atavinus sp. nov., is described based on a wingless female. A winged female similar to the earlier described Dolichoderus tauricus Dlussky, 1981 is found: due to the excellent preservation of this specimen, the new specimen and the holotype of D. tauricus are redescribed and can be reclassified as Ponerites tauricus (Dlussky, 1981), comb. nov. Oecophylla taurica sp. nov. is described based on a partly preserved imprint of a female thorax with a forewing, the venation of which allows it to be positively identified as a weaver ant. Two other species are transferred from the formal genus Camponotites to Oecophylla based on forewing venation: O. kraussei (Dlussky et Rasnitsyn, 1999), comb. nov. (Early Eocene, United States) and O. macroptera (Dlussky, 1981), comb. nov. (Middle Miocene, Stavropol, Russia). One of the studied forewing imprints is similar in venation to Paraphaenogaster microphthalmus Dlussky, 1981, described from the Middle Miocene of Vishnevaya Balka (Stavropol province, Russia) and so is attributed to this species. Dolichoderus tavridus sp. nov. is described based on a forewing.  相似文献   

14.
The smallest and most primitive Oligocene cricetid,Ulaancricetodon badamae n. gen., n. sp. is described from the Hsanda Gol Formation in Mongolia. The fossils were recovered from stratified fossil horizons immediately below and above a basalt layer dated at 31.5 Ma (40Ar/39Ar-data), that is an Early Oligocene age. Although the dental formula is muroid (1-0-0-3/1-0-0-3), the tooth morphology and tooth size ofUlaancricetodon badamae n. gen., n. sp. point to a close relationship with the zapodidHeosminthus Wang 1985, which is known from the Asian Late Eocene to Early Oligocene.  相似文献   

15.
The mollusc fauna of the early Middle Miocene (Langhian) intramontane Alpine Lake Groisenbach is described for the first time. The shells derive from the Feistring Formation in the Aflenz Basin in Austria, which was covered by Lake Groisenbach. The assemblage is moderately diverse with 12 gastropod and 2 bivalve species, suggesting shallow lacustrine and fluvial settings. Among the gastropods, only Theodoxus crenulatus (Klein, 1853) is known from other Miocene localities, whilst all other species are documented so far only from Lake Groisenbach. None of the Early and Middle Miocene lake systems of the Alpine-Carpathian Foredeep and the Balkan Peninsula displays any faunistic resemblance with this new fauna. Even coeval lake faunas from the close-by Graz Basin have no species in common with Lake Groisenbach. This pattern points to a surprising endemicity and biogeographic fragmentation in the Central European freshwater systems during the Early and Middle Miocene. The uniqueness of the newly described fauna is also indicated by the completely erratic occurrence of the otherwise African-Mediterranean genus Bulinus, which is unknown from all other central European Miocene freshwater systems. Emmericia roetzeli Harzhauser and Neubauer nov. sp., Nematurella zuschini Neubauer and Harzhauser nov. sp., Romania fastigata Neubauer and Harzhauser nov. sp., Odontohydrobia groisenbachensis Neubauer and Harzhauser nov. sp., Odontohydrobia pompatica Neubauer and Harzhauser nov. sp., Odontohydrobia styriaca Harzhauser and Neubauer nov. sp., Planorbis austroalpinus Harzhauser and Neubauer nov. sp., Gyraulus sachsenhoferi Harzhauser and Neubauer nov. sp., Bulinus corici Harzhauser and Neubauer nov. sp., Ferrissia crenellata Harzhauser and Neubauer nov. sp. and Stagnicola reinholdkunzi Harzhauser and Neubauer nov. sp. are introduced as new species.  相似文献   

16.
New taxa of Ensifera and Caelifera orthopterans (Insecta, Orthoptera), from the families Gryllotalpidae [Marchandiinae, subfam. nov. (Lower Cretaceous)], Haglotettigoniidae [?Haglotettigonia aenigmatosa, sp. nov. (Lower Cretaceous)], Tettigoniidae [Meconematinae: Archixizicus occidentalis, gen. et sp. nov. (Eocene), Eogrigoriora gracilis, gen. et sp. nov. (Eocene), Miophlugis rostratus, gen. et sp. nov. (Miocene)], Stenopelmatidae [Siinae: Electrosia baltica, gen. et sp. nov. (Eocene); Gryllacridinae: Plesiolarnaca prior, gen. et sp. nov. (Eocene)] and Tridactylidae [Mongoloxyinae: Birmitoxya intermedia, gen. et sp. nov. (Upper Cretaceous). The Eocene species Lipotactes martynovi Zeun. and L. bispinatus Weidn. are transferred to the genus Eomortoniellus Zeun. (Tettigoniidae: Tympanophorinae); Prorhaphidophora zeuneri Chop. and P. tachycinoides Chop. are transferred to the genus Protroglophilus Gor. (Rhaphidophoridae: Protroglophilinae). The Eocene species E. handlirschi Zeun., species of the genus Protroglophilus, and a possible member of the genus Succinotettix Piton (Tetrigidae: Tetriginae), as well as a Miocene representative of the genus Archaeoellipes Heads (Tridactylidae: Tridactylinae) are also discussed.  相似文献   

17.
《Comptes Rendus Palevol》2008,7(8):557-569
New observations on the Late Miocene and Earliest Pliocene mustelids from the Middle Awash of Ethiopia are presented. The Middle Awash study area samples the last six million years of African vertebrate evolutionary history. Its Latest Miocene (Asa Koma Member of the Adu-Asa Formation, 5.54–5.77 Ma) and Earliest Pliocene (Kuseralee and Gawto Members of the Sagantole Formation, 5.2 and 4.85 Ma, respectively) deposits sample a number of large and small carnivore taxa among which mustelids are numerically abundant. Among the known Late Miocene and Early Pliocene mustelid genera, the Middle Awash Late Miocene documents the earliest Mellivora in eastern Africa and its likely first appearance in Africa, a new species of Plesiogulo, and a species of Vishnuonyx. The latter possibly represents the last appearance of this genus in Africa. Torolutra ougandensis is known from both the Late Miocene and Early Pliocene deposits of the Middle Awash. The genus Sivaonyx is represented by at least two species: S. ekecaman and S. aff. S. soriae. Most of the lutrine genera documented in the Middle Awash Late Miocene/Early Pliocene are also documented in contemporaneous sites of eastern Africa. The new observations presented here show that mustelids were more diverse in the Middle Awash Late Miocene and Early Pliocene than previously documented.  相似文献   

18.
Larger benthic foraminifera (LBF) are significant proxies in biostratigraphy and also act as excellent indicators of shallow-marine carbonate environments in fossil series. The Palaeogene LBF recorded from Meghalaya, NE India (eastern part of the relic eastern Tethys/Neo-Tethys) have high potential for dating shallow-marine sediments and documenting the multiple episodes of carbonate sedimentation that have contributed to the development of the Sylhet Limestone Group. Early Eocene witnessed the proliferation of LBF species worldwide, the phenomenon better known as the Larger Foraminiferal Turnover (LFT). Genera like Alveolina, Nummulites and Orbitolites with broad species complexes thrived as the dominant LBF amidst numerous other taxa on the verge of extinction or only surviving as stable forms. The current study emphasizes on the biostratigraphic and palaeoenvironmental account of the early Eocene Umlatdoh Limestone successions outcropping in the Jaintia Hills of Meghalaya, primarily based on the recorded species of Alveolina and other larger benthic foraminifera. Five species of AlveolinaA. oblonga, A. schwageri, A. cf. ruetimeyeri, A. aff. haymanensis and A. aff. varians are recorded in the evaluated sections that indicate an early Eocene age corresponding to the Shallow Benthic Zone 10. Major carbonate facies types in the present assessment include oolitic-smaller benthic foraminiferal -green algal grainstone–packstone, smaller miliolid-Alveolina grainstone, green algal-benthic foraminiferal grainstone, larger porcellaneous (Alveolina) grainstone-packstone, Alveolina-nummulitid grainstone-rudstone, and nummulitid grainstone-rudstone, which indicate a shallow marine, high-energy depositional environment ranging from shoal-sandy bars to a distal inner ramp setting.  相似文献   

19.
Studies of fossil molluscs from Early Miocene deposits at Napak, Uganda, reveal that between 20 and 18.5 Ma, there were various kinds of palaeoenvironments on the flanks of the volcano ranging from forest to open country. The basal Iriri Member contains fluvial deposits from which freshwater gastropods and bivalves have been collected. The younger Napak Member is subaerial in facies, and has yielded a predominantly forest assemblage of gastropods, but with some indications of open country species at one of the sites. Napak has yielded a rich and diverse primate fauna, including the large ape Ugandapithecus major, the small ape Micropithecus clarki, the earliest known cercopithecid in the world (Prohylobates sp.) and several galagids (Mioeuoticus bishopi) among other less well-known taxa.  相似文献   

20.
A marine fossil assemblage from the Late Triassic (Early Carnian) Cassian Formation is reported. It was retrieved by bulk sampling, including wet sieving and quantitative picking, and by quantitative surface collection. The collection consists of c. 460 specimens (foraminiferans not included) representing 54 species. In terms of abundance and species richness, it is strongly dominated by molluscs, especially gastropods. 97 % of the individuals are molluscs. The most abundant species are the gastropods Goniospira armata, Schartia carinata and Helenostylina convexa, followed by the scaphopod Plagioglypta undulata and the bivalve Palaeonucula strigilata. Disarticulated echinoderm ossicles (mostly echinoids, crinoids, few holothurians) comprise almost all of the rest of the assemblage. The studied assemblage shows moderate diversity, similar to those of previously reported assemblages or associations from basinal settings. However, it differs considerably in taxonomic composition from previously described associations of the Cassian Formation. The abundance of small gastropods is a result of their primary abundance in these ancient living communities and of the sampling method (sieving at 0.5 mm), because most of the previous associations were obtained by performing surface collections, in which small gastropods are easily overlooked. The fauna is interpreted as an autochthonous soft bottom assemblage dominated by species that lived in low epifaunal to shallow infaunal habitats. Detritivory, deposit feeding and microcarnivory represent the main feeding types. Most of the species were fully motile but slow, and either infaunal (scaphopods, nuculids, the gastropod Domerionina) or epifaunal (most other gastropods, echinoids). The present assemblage underlines the pronounced heterogeneity of the Cassian biota. The low grade of lithification and diagenetic alteration facilitates bulk sampling and the investigation of small species. This minimizes possible sampling and preservation biases, so the studied assemblage reflects the alpha diversity of this ancient living community to an unusually high degree. The following gastropod taxa are new: Helenostylina convexa n. sp., Schartia carinata n. gen. n. sp., Schartiinae n. subfam.; Cassianastraea Bandel non Volz is replaced with Bandelastraea nom. nov.  相似文献   

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