A eutherian mammal from the Early Cretaceous of Russia and biostratigraphy of the Asian Early Cretaceous vertebrate assemblages

Prokennalestes abramovi n.sp. is described based on M2 from the upper Barremian-middle Aptian (Early Cretaceous) Mogoito locality in Transbaikalia, Russia. It differs from the Mongolian species of Prokennalestes (Khoboor, early Albian) by a combination of one primitive character (steeper and shorter lingual slopes of the paracone and metacone), one more derived character (larger size), and some characters of uncertain polarity (small preparastyle, lack of labial cuspules along the ectoflexus). P. abramovi n.sp. is the oldest eutherian mammal so far described, and its discovery extends the known geological range of Eutheria by 10-15 Ma. The Tsagantsabian land-vertebrate biochron can be defined by a dominance of sinemyid turtles; the Khukhtekian by a dominance of macrobaenids.     

Two New Species of the Early Cretaceous Filicinae and Their Taxonomical Study

Mainly based on the characters of the fertile segments, two new species of the Early Cretaceous ferns:Athyrium hulunianurn Chen, Ren et Deng (sp. nov. )and A. hailaerianurn Deng et Chen (sp. nov. ) have been nominated from the Yimin Formation, Zhalainuoer, Nei Monggol.     

A new scorpion fossil from the Cretaceous amber of Myanmar (Burma). New phylogenetic implications

A fossil scorpion belonging to a new family, genus and species, Chaerilobuthus complexus gen. n., sp. n., is described from Cretaceous amber of Myanmar (Burma). This is the third species and the fourth scorpion specimen to have been found and described from Burmese amber. The new family seems quite distinct from the family Archaeobuthidae Lourenço, 2001 described from Cretaceous amber of Lebanon.     

Two new non-biting midges from the Early Cretaceous Lebanese amber (Diptera: Chironomidae)

Abstract

Two chironomid flies, Ziadeus kamili n. gen., n. sp. and Paicheleria magnifica n. gen., n. sp., respectively attributed to the recent subfamilies Tanypodinae and Prodiamesinae, are described from the Early Cretaceous Lebanese amber. Although very old, this non-biting midge fauna was very diverse with no less than 11 genera and species. However, it was also strongly different from the recent faunas for the complete absence of the Chironominae, that is today the dominant subfamily. The development of the modern chironomid fauna occurred during the Late Cretaceous and/or the Early Paleogene, but when and how?     

A new species of Baiera from the Early Cretaceous Jehol Biota of southeastern Jilin,China

The Early Cretaceous Yingzuilazi Formation is exposed in the Baishan Basin, Baishan region of the southeastern Jilin Province, China. So far, no reports on fossil plants from this formation have been published. During recent field excursions, abundant faunal remains belonging to the Early Cretaceous Lycoptera–Ephemeropsis–Eosestheria assemblage of the Jehol Biota and numerous fossil plants were collected from the lacustrine beds of the lower part of this formation. A new species of Ginkgoales from this formation, Baiera baishanensis n. sp., is described based upon the leaf morphology and epidermal characters. This is the first report about fossil plants from the Yinzuilazi Formation, the easternmost distribution area of the Jehol Biota. The discovery of the new species extends significantly the stratigraphic and geographic distribution of Baiera in the Early Cretaceous Jehol Biota as well as the Eurasia. It also shows that Baiera was a common member of Ginkgophytes once lived in the Early Cretaceous deciduous forest of Northeast China. The new species also improves our knowledge on understanding the leaf morphology, epidermal features, and diversity of Baiera during the Early Cretaceous. Analysis of the epidermal characters of the new species and other associated plants reveals that the plants grew in a warm and humid climate in the temperate zone. The presence of some deciduous plants, including gingkgoaleans, czekanowskialeans, and some conifers, demonstrates a climate with seasonal fluctuations and precipitation.     

Plants of Leptostrobus Heer （Czekanowskiales） from the Early Cretaceous and Late Triassic of China, with Discussion of the Genus

Investigation of the Mesozoic seed plant Leptostrobus Heer from the Yangcaogou Formation of the Late Triassic and the Yixian Formation of the Early Cretaceous, Liaoning Province, China, provides new Insight Into Its general morphology and geographical distribution. The materials of L. cancer from the Yixian Formation described herein are later than all the past findings of this species and add to the record of L. cancer during the Early Cretaceous. Based on well-preserved specimens, the specific diagnosis Is slightly emended and the reconstructlon of L. cancer Is perfected. The materials from the Yangcaogou Formation of the Late Triassic are placed in L. spheericus, in addition, we review the history of investigation of the genus Leptostrobus since its establishment in 1876 and discuss the main characteristics of each species.     

The oldest higher true crabs (Crustacea: Decapoda: Brachyura): insights from the Early Cretaceous of the Americas

Despite the extensive fossil record of higher crabs (Eubrachyura) from Late Cretaceous and Cenozoic rocks worldwide, their Early Cretaceous occurrences are scarce and fragmentary, obscuring our understanding of their early evolution. Until now, representatives of only two families of eubrachyuran‐like crabs were known from the Early Cretaceous: Componocancridae and Tepexicarcinidae fam. nov., both monospecific lineages from the Albian (~110–100 Ma) of North and Central America, respectively. The discovery of Telamonocarcinus antiquus sp. nov. (Telamonocarcinidae) from the early Albian of Colombia, South America (~110 Ma), increases to three the number of known Early Cretaceous eubrachyuran‐like families. The ages and geographical distributions of the oldest eubrachyuran‐like taxa (i.e. Componocancridae, Telamonocarcinidae and Tepexicarcinidae fam. nov.) suggest that the oldest higher true crabs might have originated in the Americas; that they were already morphologically diverse by the late Early Cretaceous; and that their most recent common ancestor must be rooted in the Early Cretaceous, or even the Late Jurassic.     

A new species of <Emphasis Type="Italic">Baierella</Emphasis> from the Krasnyi Yar locality,Early Cretaceous of western Transbaikalia

Plant remains of Baierella R. Potonié (Ginkgoales) were found for the first time in the Lower Cretaceous deposits of the Khilok Formation (Buryatia Republic), where they form a thin coal bed. A new species, B. averianovii, is described from the Krasnyi Yar locality. The monodominant burial of the new species in combination with pollen grains of Ginkgocycadophytus prevailing in the relevant palynological assemblage allows the authors to reconstruct a monospecific woody wetland plant community.     

Two Angiosperm Reproductive Organs from the Early Cretaceous of China

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.     

The palaeoecology of the dinosaurs of the Wessex Formation (Wealden Group, Early Cretaceous), Isle of Wight, Southern England

The Wessex Formation on the Isle of Wight yields an Early Cretaceous dinosaur fauna. Sedimentological evidence shows that this represents a mosaic of fluvial, floodplain and lacustrine environments within a relatively narrow east-west oriented valley. The vegetational cover on the alluvial plain had a savannah-or chaparral-like aspect, probably of low productivity. The relative scarcity of small aquatic vertebrates, absence of coals, abundance of oxidixed sediments and the presence of immature calcretes indicate seasonal water supply. The dinosaur taxa compising the Wessex Formation faunal assemblage represent a single palaeocommunity which inhabited the local alluvial plain, although some species may have been transient. The fauna had a relatively low diversity and this is attributed to the low productivity of the local vegetation. Iguanodontids and Hypsilophodon were the dominant elements in the fauna. In contrast to Late Jurassic dinosaur faunas, sauropods are less abundant in the Wessex Formation, although they remain taxonomically diverse. It is concluded that climatic changes which took place in the Late Jurassic or Early Cretaceous resulted in the appearance of low productivity vegetation and that this was incapable of supporting large sauropod populations.     

Early Cretaceous non‐marine Ostracoda from the North Falkland Basin,South Atlantic

Twenty‐seven species of well‐preserved and abundant Early Cretaceous non‐marine ostracod crustaceans were recovered from the North Falkland Basin. The assemblage is unusually diverse for a non‐marine palaeoenvironment and is sourced from cuttings samples collected during 2011 drilling of wells by Desire and Rockhopper Exploration, in the northern and southern areas of the basin. Ostracoda are entirely undocumented in published accounts from this basin, and all but one species appear to be new to science. For the new taxa, one new family (Alloiocyprideidae; type genus Hourcqia) is proposed and includes Hourcqia woodi sp. nov. Four new genera are erected: Falklandicypris gen. nov.; type species F. petrasaltata sp. nov., Gangamoncythere gen. nov.; type species G. colini sp. nov., Paraplesiocypridea gen. nov.; type species P. alloios sp. nov., and Musacchiocythere gen nov.; type species M. sarunata (Musacchio, 1978 ). Nine other species are described as new and are Falklandicypris desiderata, Clinocypris epacrus, Cypria poietes, Ilhasina? leiodermatus, Looneyellopsis tuberculatus, Theriosynoecum petasmathylacus, Theriosynoecum ballentae, Timiriasevia fluitans, and Vecticypris samesi. The remainder are left in open nomenclature due to paucity of material. The ostracod assemblage is largely restricted to the southern part of the basin (wells 25/5‐1 and 26/6‐1). In the northern part of the basin only four species, dominated by Vecticypris samesi, are present and with one possible exception are restricted there. There appears to have been little or no interchange of species suggesting that a barrier probably existed between the northern and southern regions. The more diverse southern assemblage indicates that more favourable conditions existed to the south. Stratigraphically, a distinct change in faunal composition recorded in both southern wells is likely to be an isochronous event correlatable across the southern area, and of an age no younger than Hauterivian.     

Unusual assemblages of Late Cretaceous silicoflagellates from the Canadian Archipelago

Devon and Ellef Ringnes islands in the Canadian Arctic Archipelago contain well-preserved Santonian through early Campanian silicoflagellates. These occur in three unusual assemblages, which comprise three biostratigraphic zones. The oldest, the Vallacerta tumidula Partial Range Zone of Santonian age, contains an extremely variable microflora that includes species of the poorly-known genus Variramus, two new species of Cornua, and a new genus Umpiocha. The Schulzyocha ruppelii Range Zone of early Campanian age includes several species of the new genus Schulzyocha, reflecting quadrate silicoflagellate skeletal morphologies that lack a basal structure. The youngest assemblage includes the poorly-known species Cornua trifurcata, the nominative taxon of the C. trifurcata Partial Range Zone (proposed by McCartney et al., in press c; emended herein), which allows a correlation with a silicoflagellate-bearing sequence from the Horton River area, Northwest Territories of Canada. This report presents information on 24 silicoflagellate taxa, proposes 2 new genera, Schulzyocha and Umpiocha, and describes 13 new species and 1 new combination. All of these new taxa disappear by the top of the Campanian Cornua trifurcata Partial Range Zone. These assemblages reveal a new history of silicoflagellate evolution prior to the late Campanian, the period from which most of our prior knowledge about Cretaceous silicoflagellates was derived. The assemblages show progressive change from skeletons with highly variable morphologies to more stable silicoflagellate skeletal geometry. Two important Corbisema species, C. apiculata and C. archangelskiana, appear to be derived from separate lines within Cornua in the latest Santonian and early Campanian. The important Cretaceous genus Lyramula makes its first appearance at the beginning of the Campanian.     

A new marsilealean fern species from the Early Cretaceous of Jordan

Leaflets of Marsileaceae are described from the Albian (Early Cretaceous) strata of Jordan. The fossils are from the Jarash Formation (Kurnub Group) and are found in fluvial sediments along with water lily leaves. The small wedge-shaped leaves have dichotomous veins that anastomose and form a marginal vein. Based on comparisons to living genera, Marsileaceaephyllum mahisensis Hu, Taylor, Brenner et Basha, n. sp., is most similar to Marsilea, in particular, with terrestrial leaflet forms; yet, it is distinct from living and fossil species by its small size and the few dichotomously branched middle veins that have a monopodial course. In addition, a single similar-veined smaller leaf with a retuse apex is thought to be a juvenile leaf of the same species. This is the first megafossil evidence of the family from Africa/Arabian Peninsula.     

A new species of the spore genus Costatoperforosporites from Early Cretaceous deposits in Portugal and its taxonomic and palaeoenvironmental significance

A new species of spore, Costatoperforosporites friisiae sp. nov., is described from the Early Cretaceous (late Aptian–early Albian) deposits of Catefica in the Lusitanian Basin, western Portugal. Although the morphology of the muri is clearly of the Cicatricosisporites type, the presence of micropores on these sculptural elements and within the intervening grooves is a particularly distinctive feature and more typical of spores that have been attributed previously to Costatoperforosporites. As a result, this genus is emended not only to accommodate Costatoperforosporites friisiae but also to differentiate it more clearly from other, similar, murornate genera. It is considered to represent the family Anemiaceae. So far, Costatoperforosporites friisiae has only been encountered in the Catefica palynoflora. The presence of many other pteridophyte spores, especially of schizaealean derivation, together with abundant cheirolepidiacean remains at this locality, strongly suggests a warm, moist climate and diverse source vegetation.     

Plant remains from Early Cretaceous deposits on the Goban Spur,Bay of Biscay,North Atlantic Ocean,and their palaeoenvironmental significance

Site 549 of the Deep Sea Drilling Project was drilled on the Goban Spur in the Bay of Biscay in 1981. The core recovered from this North Atlantic location included 290 m of Barremian and possibly partly Hauterivian “syn-rift” deposits overlain unconformably by rocks of early Albian age. The number and variety of spores and pollen grains in the palynomorph assemblages and associated palynofacies through these units together with the presence of some pieces of wood, fragments of foliage, and a few megaspores in the lowest part of the Cretaceous succession suggest that the source area vegetation was, at least initially, relatively close to the site of deposition. Ginkgoalean, bennettitalean, and other gymnosperm groups are represented in the plant mesofossil assemblage but most of the fragments of foliage show cheirolepidiaceous characteristics. Five species belonging to this family have been identified and described. Two of these, Frenelopsis atlantica Zhou and Batten and Frenelopsis? alvinii Zhou and Batten, are new and one is unnamed. The composition of the three informally identified suites of spore and pollen assemblages recovered from 49 samples through the Early Cretaceous succession is consistent with age determinations of parts of it determined previously on the basis of dinoflagellate cysts, foraminifera, nannoplankton, and other fossils.     

Sporo-Pollen Assemblages from Late Phase of Early Cretaceous in Minhe Basin

Plenty of sporo-pollen fossils were found from the Upper Subformation of Hekou Formation at Chaijiatai, Lanzhou of Gansu, Minhe Basin. The sporo-pollen assemblage of the upper stratum of the Upper Suhformation was named as Schizaeoisporites-Cicatricosisporites. It could be further divided into two subassemblages. The upper one was Classopollis-Schiza- eoisporites, and the lower one was Piceapollenites-Cicatricosisporites. By analysing the periods of the important species and genera in the assemblage and comparing with the known assemblages in various districts, the author cosidered that the geologic age of the assemblage was the late phase of Early Cretaceous (Aptian-Alhian). The age of the second subassemblage was later which was Albian. So far, the stratum where the sporo-pollen fossils assemblage were found was the uppermost one of the Lower Cretaceous that have been found in Minhe Basin.     

The first dinosaur egg from the Lower Cretaceous of Western Siberia,Russia

The Lower Cretaceous Ilek Formation in Western Siberia (Russia) has yielded various vertebrate fossils, including skeletal remains of dinosaurs. Here we report on a fragmentary theropod egg from the vertebrate locality Shestakovo 3 of the Ilek Formation in Kemerovo Province. We assign the specimen to the oogenus Prismatoolithus (oofamily Prismatoolithidae) as Prismatoolithus ilekensis oosp. nov., on the basis of the following unique combination of characters: ovoid-shaped egg; thin eggshell 300–330 μm thick; angustiprismatic morphotype; eggshell with three different layers; gradual transition between mammillary layer and prismatic layer; abrupt contact between prismatic layer and external layer; mammillary layer to prismatic layer to external layer thickness ratio is 1:3:0.6; prismatic layer with ill-defined squamatic texture; angusticanaliculate pore system; and smooth outer surface. Like other Early Creataceous Prismatoolithus, the egg of Prismatoolithus ilekensis oosp. nov. was laid by a small bodied theropod dinosaur (troodontid or primitive bird) and this taxonomic attribution is supported by results of our phylogenetic analysis. Prismatoolithus ilekensis oosp. nov. is the first Early Cretaceous ootaxon from Russia.

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