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1.
Isolated teeth of fossil lancetfishes (Neoteleostei, Alepisauroidei) are reported from Early Cretaceous strata of the Oliete subbasin (Iberian basin) in NE Spain. These are the oldest remains attributable to alepisauriform teleosts. The fossil-bearing strata are dated as lower Barremian. The teeth were recovered from shallow marine to lagoonal sediments. They closely resemble teeth of the fossil alepisauriforms Enchodus and Cimolichthys in overall morphology. The combination of fang-like morphology, sculpture consisting of apico-basal striations, postapical barb, absence of distal cutting edge, and wide pulp cavity surrounded by a rather thin layer of dentine is interpreted as the most basal tooth pattern in alepisauriforms. These remains may be isolated, but this study emphasizes the true value of such remains for palaeobiological studies, predicting the fossils provide characters for phylogenetic analyses.  相似文献   

2.
A virtually complete specimen of the family Mesoraphidiidae (Insecta: Raphidioptera) is described as Cantabroraphidia marcanoi n. gen., n. sp. It was found in early Albian amber from a new deposit named El Soplao within the Las Peñosas Fm. in northwestern Cantabria (Spain). It has been compared to all adult fossils placed in the Mesozoic family Mesoraphidiidae. Some taxonomical comments are provided, and we propose to restore the genus Yanoraphidia Ren 1995 and the combination Yanoraphidia gaoi Ren 1995 stat. rest., provisionally retained in the family Mesoraphidiidae.  相似文献   

3.
Spinosaurids are one of the most abundant theropods from the Early Cretaceous of the Iberian Peninsula. The published fossil record consists mainly of teeth. A good example is La Cantalera-1 site in the Blesa Formation (Spain). This site represents a marshy environment with periodic droughts, resulting in a non-permanent body of water. Theropod dinosaur teeth are frequent. Seventeen spinosaurid teeth have been studied using qualitative and quantitative features, including a statistical analysis, in order to compare them with the known spinosaurid record from Spain. In La Cantalera-1 we recognise two different morphotypes: Baryonychinae indet. and Spinosaurinae? indet. Baryonychinae indet. was produced by baryonychines close to Baryonyx; teeth with similar morphology have been described in other sites from the Early Cretaceous of the Iberian Peninsula. Teeth tentatively attributed to Spinosaurinae? indet. were produced by spinosaurines close to Spinosaurus. This morphotype could provide new evidence of the presence of spinosaurines in the Early Cretaceous of the Iberian Peninsula. The small size of the teeth from La Cantalera-1 when compared with those from other sites is interpreted as the result of the conditions characteristic of the deposit area, which represents an ecosystem unable to sustain large-sized organisms.  相似文献   

4.
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.  相似文献   

5.
Abstract

A report on two new collections of fresh- and brackish water molluscs in Egypt is filling gaps in the generally known distribution pattern. The recent status of the mollusc fauna of Birket Qarun (Fayum), changed by introduction of marine species into the brackish water lake, is documented.  相似文献   

6.
Two new taxa of freshwater mussels (Bivalvia: Unionida) from the Aptian Crato Formation of the Araripe Basin, NE Brazil, are described. The fossil bivalves are confined to 30- to 130-cm-thick bioturbated mudstones overlying the fossil-rich laminated limestones of the Crato Formation Konservat-Lagerstätte. Individuals are often preserved with closed or splayed articulated valves, some of them potentially in life position, forming an autochthonous to parautochthonous assemblage. Monginellopsis bellaradiata nov. gen., nov. sp. shares key characters with the Trigonioidoidea: (i) the anterior pedal retractor muscle scar is clearly separated from the anterior adductor muscle scar; (ii) the shell has fold-like radial ribs on the posterior half; (iii) a right valve anterior tooth has a striated facet. Araripenaia elliptica nov. gen., nov. sp. is the most abundant and widely distributed unionid of the Crato Formation. Its ornament of anterior inverted V-shaped riblets, and central and posterior radial and sub-radial riblets resembles modern and fossil Hyriidae from the Americas, but also Trigonioidoidea from Eurasia. Its dentition of two smooth anterior pseudocardinals and two smooth posterior laterals in each valve provides no further clues for systematic assignment; muscle scars are not preserved. Assignment to the Hyriidae would make Araripenaia the oldest member of this family known from South America. Moreover, this bivalve assemblage of trigonioidoidids, hyriids, and previously reported silesunionoids suggests palaeobiogeographic links to other areas in both Gondwana and Laurasia.  相似文献   

7.
Extensive sampling of several Barremian and Albian–Cenomanian levels across the Aguilón, Oliete and Aliaga subbasins of the Iberian Basin, north‐east Spain, yielded abundant material of new or so far poorly known neoselachians. The faunas consist of 16 different species, five of which represent new species and two new genera: Cantioscyllium brachyplicatum sp. nov. , Platypterix venustulus gen. et sp. nov. , Ptychotrygon pustulata sp. nov. , Ptychotrygon striata sp. nov. and Iberotrygon plagiolophus gen. et sp. nov. In addition, teeth of Heterodontus cf. H. carerens, Lamniformes indet., Pteroscyllium sp., Scyliorhinidae indet., Rhinobatos sp., Spathobatis sp., Belemnobatis sp., Ptychotrygon geyeri, Ptychotrygon sp. and Celtipristis herreroi are described. The new family Ptychotrygonidae is defined. The localities comprise palaeoenvironments ranging from lacustrine and shallow lake to open marine settings. Neoselachians are almost completely absent from continental settings in the Barremian, as a result of prevailing freshwater conditions, but became more abundant in marine strata. The Albian–Cenomanian selachian assemblage is the most profuse and diverse of the three assemblages studied. It is dominated by small, benthic and near‐coastal taxa, for instance Cantioscyllium and Ptychotrygon, and contains several new species, including an endemic batoid, Iberotrygon plagiolophus gen. et sp. nov. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 155 , 316–347.  相似文献   

8.
A brief outline is presented of the geological conditions prevailing in the hard-water lake that produced the Las Hoyas fossiliferous site in the Serranía de Cuenca (north-east central Spain). The corresponding Barremian laminated limestones contain varied fossil remains including plants. The fern component of the assemblage is described in the present paper. Ten taxa are referable to the families Matoniaceae, Dicksoniaceae and Schizaeaceae, whilst eight are unclassified. A new species of Dicksoniaceae is described: Coniopteris laciniata. Three species, Pelletixia valdensis, Cladophlebis albertsii, and Sphenopteris fontainei, are recorded here for the first time outside the English Wealden; one species, Acrostichopteris foliosa, is new to the Barremian of Europe. The fern assemblage from the Las Hoyas site is most similar to that of the English Wealden. The xeromorph character of some species is noted.   Although the specimens from Las Hoyas are generally small, even tiny, most are still identifiable leaf fragments preserved as imprints on platy limestone. Epidermal detail has been obtained from a few impressions. Some rather delicate remains, such as indusia, a crozier with pinnules, and fragments of Pelletixia valdensis occur, thus suggesting limited residence time in water.  相似文献   

9.
Vegetative plant remains and microsporangiate cones, related to the fossil genera Frenelopsis and Classostrobus respectively, were studied in three localities from the Lower Cretaceous of the Pyrenees and Iberian Ranges (Spain). Sterile remains belong to three different species: F. Rubiesensis Barale, F. Ugnaensis sp. nov. and F. Turolensis sp. nov. The male cones Classostrobus ugnaensis sp. nov. and C. Turolensis sp. nov. are associated with the two latter species respectively, and C. Turolensis is found in connection with F. Turolensis . Internodes of F. Ugnaensis display small hemispherical papillae and long conical hairs covering the entire cuticle surface, while F. Turolensis has a strip of hairs near the leaf margin, in addition to more massive outer stomatal papillae and higher stomatal density. The tiny cones of C. Ugnaensis bear microsporophyll cuticles capped with vermiculate flattened papillae and a fringe of marginal hairs, while C. Turolensis has a central area of microsporophylls covered by long conical hairs. Sedimentological and taphonomic analyses show that the assemblages studied belong to a wide spectrum of habitats. These indicate that Spanish Lower Cretaceous frenelopsids were xeromorphic plants, able to adapt to helophytic and riparian habitats, and grew in brackish coastal marshes and fluvio–lacustrine freshwater environments.  相似文献   

10.
A tall-spined ornithopod dinosaur from the Pinilla de los Moros Formation (Upper Hauterivian-Lower Barremian) of Salas de los Infantes (Burgos, Spain) is described. The material consists of seven associated axial remains, including five middle dorsal vertebrae, a fragmentary neural spine and a dorsal rib, from a single medium-sized individual. This material was previously referred to Iguanodon cf. fittoni. It is characterised by having a high dorsal neurapophysis that is approximately 4.5 times the height of the centrum. The elongation and vertical orientation of the dorsal neural spines allow it to be distinguished from other ornithopods from the Wealden of Europe, including Hypselospinus and Barilium from the Valanginian, and Iguanodon and Mantellisaurus from the Barremian-Aptian. The material is here referred to Iguanodontia indet. because it is so incomplete, but it is potentially a distinct taxon. Among the ornithopods, only Ouranosaurus and the hadrosaurid Hypacrosaurus possess higher dorsal neural spines.  相似文献   

11.
In order to assess Early Cretaceous nannoplankton biogeography, we studied a series of sites which provide a north–south transect across the Atlantic Ocean, supplemented by sections from the North Sea Basin, Barents Sea, Falkland Plateau, Weddell Sea (Antarctica), Argo Abyssal Plain (NW of Australia) and Neuquén Basin (Argentina). Quantitative assemblage data were gathered from each site for seven time-slices within the Berriasian to Barremian interval, each horizon being determined by a nannofossil datum. Trends in species relative abundance and measures of diversity, evenness and richness provide revealing biogeographic information. A broad, low- to mid-palaeolatitude zone (50°N–50°S) is flanked in both Northern and Southern Hemispheres by distinct high-palaeolatitude zones. Major changes in assemblage abundance and composition occur across a sharp biogeographic ‘front’ at around 50°N and S palaeolatitude. High-palaeolatitude assemblages are lower in species richness and diversity and characterised by the presence of abundant, typically bipolar, taxa (e.g. Crucibiscutum salebrosum). A less distinct biogeographic boundary at 40°N is distinguished by the presence/absence of rarer, but biogeographically significant, taxa, many of which have previously been assigned to Boreal or Tethyan provinces. Continental shelf sites are characterised by lower-diversity assemblages with common to dominant diagnostic taxa, which vary with palaeolatitude: Nannoconus and Micrantholithus at low palaeolatitudes, and Biscutum constans and Zeugrhabdotus spp. at higher palaeolatitudes. The latter two taxa are considered to be indicative of elevated surface-water fertility and the former two may have been similarly adapted. The genus Watznoueria is ubiquitously dominant, giving the populations an unevenness, which appears to be a common feature throughout coccolithophore history.  相似文献   

12.
Abstract: The smallest living amniotes are all lizards, but the fossil history of this size trait in Squamata is difficult to follow because small skeletons have low preservation potential and are often hard to detect in the field. A new squamate taxon, Jucaraseps grandipes gen. et sp. nov., is here described on the basis of an articulated skeleton from the Early Cretaceous Spanish lagerstätten of Las Hoyas. It differs from other known Mesozoic lizards in combining very small body size with a short rostrum, low maxillary tooth count, a relatively slender and elongated body, and short limbs with large hind feet. Phylogenetic analysis using TNT places it on the stem of a clade encompassing scincomorphs, gekkotans, snakes, amphisbaenians and anguimorphs. Comparison with modern lizards suggests it was probably a cryptic surface or subsurface ground dweller but not a burrower.  相似文献   

13.
Zhang W  Yao Y  Ren D 《ZooKeys》2011,(130):185-198
A new genus with a new species of Saldidae, Brevrimatus pulchalifergen. et sp. n., is described and illustrated. The fossil specimen was found from the Early Cretaceous Yixian Formation of Duolun County, Inner Mongolia, China. Phylogenetic analyses within Saldidae were performed, and the results indicate Brevrimatus pulchalifergen. et sp. n. should be assigned to the subfamily Chiloxanthinae.  相似文献   

14.
The new scleractinian coral genusHexasmiliopsis is described on the basis of material from the Early Aptian (Early Cretaceous) of Murcia (Spain). The new genus of the Heterocoeniidae family is characterised by its solitary growth form, a very strong main septum and the presence of apophysal septa. It is closely related to the generaHexasmilia (phaceloid growth form),Rodinosmilia andTiarasmilia (both without main septum). The genus is monospecific and represents only the type species,Hexasmiliopsis saldanai.   相似文献   

15.
Serpulids and other related tube-dwelling polychaetes are often ignored when found as fossil remains. They are, however, a widespread and important group today, and abundant literature has been published on them. Knowledge of fossil serpulids is centered on European material, and little has already been done on South American fossil calcareous tubes. In this paper, seven serpulid and sabellid morphotypes are described from the Early Cretaceous marine Agrio Formation of Argentina, revealing a diversity of worms recorded as encrusters on bivalves, ammonites and corals. Sabellids are represented by Glomerula cf. serpentina. Serpulids are represented by two subfamilies: “Serpulinae” includes Mucroserpula mucroserpula, Parsimonia antiquata, Placostegus cf. conchophilus, Propomatoceros semicostatus and P. sulcicarinatus; Spirorbinae is represented by heavily worn tiny coiled tubes assigned to ?Neomicrorbis. Serpulids and sabellids are one of the main components of the mollusk-encrusting fauna recorded in the Agrio Formation, along with small oysters but much more diverse. They are most commonly found as post-mortem encrusters, but some cases of unquestionable living interaction are also found, such as serpulid tubes embedded on coral branches. They are often overgrown by bryozoans, and sometimes by oysters; they frequently occur aggregated.  相似文献   

16.
Abstract: The fauna of false fairy wasps (Proctotrupomorpha: Bipetiolarida: Mymarommatoidea) occurring in Early Cretaceous (Albian) amber from north and north‐eastern Spain (Moraza, San Just, and El Soplao outcrops) is described. In total, 12 specimens have been recovered and four species recognized, all new: Alavaromma orchamum gen. nov. and sp. nov. (Alavarommatidae fam. nov.), Archaeromma hispanicum sp. nov. (Mymarommatidae), Galloromma alavaensis sp. nov., and G. turolensis sp. nov. (Gallorommatidae). The study indicates the necessity of revision and maybe fusion of both superfamilies, Mymarommatoidea and Serphitoidea, as the boundaries between them are less and less defined. However, major classificatory rearrangements must await the completion of the cladistic studies presently underway.  相似文献   

17.
Two fossil reproductive organs of early angiosperms were collected from the Yanji Basin, Jilin Province of China. The assemblage of fossil plants consist mainly of pteridophytes, gymnosperms and a few angiospoermms. The present paper only reports the two reproductive organs of angiosperms. They are Archimagnolia rostrato-stylosa gen.et sp. nov., Eucommioites orientalis sp.nov. The first is a slightly elongated floral axis(receptacle), with about 20 carpels helically arranged. The carpels are free from each other and attenuated into a beak-like structure at the apex, with the base inserted into the receptacle. A comparison with living plants indicated its close relationship with some members of the Magnoliaceae. The second is a samara, similar to a fruit of the genus Eucommia, narrow-oblong, 2-lobed at the apex with the lobes stigmatic on theinner side. The seed is situated at the middle of fruit, oblong in shape.  相似文献   

18.
Abstract: The mid‐Cretaceous bivalve Goshoraia Tamura, 1977, endemic to Japan, is an early example of shallow‐marine siphonate bivalves of the family Veneridae Rafinesque, 1815. Three species, including one new, are here described: Goshoraia minor Tashiro and Kozai, 1989 (Aptian), G. crenulata (Matsumoto, 1938; Albian–lower Cenomanian) and G. maedai sp. nov. (middle to ?upper Cenomanian). The habitats of Goshoraia have been extensively compared with those of common Cretaceous, nonsiphonate burrowers, such as trigoniids, which range from tidal flat and shoreface to shelf environments. Depth of burial, which can be estimated from the extent of the pallial sinus, increases from the ancestral G. minor to its descendants G. crenulata and G. maedai sp. nov., documenting that the ability to burrow within this genus improved in time. These morphological and palaeoecological changes may be related to the Mesozoic marine revolution during the mid‐Cretaceous.  相似文献   

19.
Mesozoic orthopterans of the family Elcanidae are reported (as nymphs) in amber, from the latest Albian-Cenomanian of northern Myanmar and the Albian of northern Spain. Four distinct new species in two new genera occur, Burmelcana longirostris n. gen, n. sp. in amber from Myanmar and Hispanelcana arilloi n. gen, n. sp., H. alavensis n. sp. and H. lopezvallei n. sp. from Spanish amber. Detailed preservation reveals the fine structure of the tibial spurs and spines that are so distinctive to Elcanidae, as well as details of the abdominal styli, cerci, tarsomeres, and mouthparts. Elcanidae and their stem group, Permelcanidae, are known from the Early Permian to the Early Cretaceous (Aptian), so the amber fossils represent the latest known occurrence of this clade.  相似文献   

20.
Based upon the characters of the fertile segments and the reproductive structures, four early Cretaceous monolete spore ferns: Athyrium asymmetricum (Meng) comb. nov. of Athyriaceae, Asplenium popovii Samylina of Aspleniaceae, Dryopterites gracilis sp. nov. and D. liaoningensis sp. nov. of Dryopteriaceae have been described from Xiaoming′anbei Formation, Tiefa Basin, Liaoning Province, China.  相似文献   

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