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1.
A new pycnosteid species, Schizosteus shkurlatensis sp. nov. (Agnatha, Psammosteiformes), from the Staryi Oskol beds (Givetian, Middle Devonian) of the Voronezh Region is described. This is the first species of the genus Schizosteus Obruchev from the Central Devonian Field. The similarity between species of this genus and early species of Psammolepis is discussed.  相似文献   

2.
《Palaeoworld》2016,25(4):639-646
Additional specimens of rhynchonellide brachiopods from the marly limestones in the Yidade Formation at the Panxi section in eastern Yunnan have been ascribed to the species “Paurorhynchasquamosa Wang, 1956 and “P.depressa Wang, 1956. The two species have been used frequently as index fossils for the Frasnian (Upper Devonian), but their taxonomic assignments are problematic because their internal structures remain unknown. In this study, detailed systematical examinations on both external characters and internal structures revealed by serial sections suggest that the two species are more appropriately assigned to the genus Hadrotatorhynchus Sartenaer, 1986. Based on the stratigraphical distributions of Hadrotatorhynchus and the conodonts in the upper unit of the Yidade Formation, the Hadrotatorhynchus-bearing horizons are re-considered as the uppermost Givetian (Middle Devonian) rather than Frasnian stage, although the precise position of the Middle/Upper Devonian boundary still depends on further investigations of high-resolution biostratigraphy.  相似文献   

3.
Liverworts are generally regarded as rare elements in Palaeozoic floral assemblages. However, a focus on dark gray to black shales and siltstones in the Middle–Late Devonian Catskill Delta of eastern New York shows that liverworts are locally quite common as well-preserved, apparently parautochthonous specimens in thin, lenticular, dark gray–black shale and siltstone lenses. These lenses are either dysoxic–anoxic lacustrine or estuarine facies deposited under oxygen-stratified water masses or rapidly deposited flood plain deposits that were not oxidized after deposition. Carbonized remains of the upper Middle Devonian (Givetian) liverwort Metzgeriothallus sharonae sp. nov. are locally common in these lenses. Well-preserved thalli (gametophytes) are only evident by projecting polarized light on the shale and siltstone surfaces. An associated sporophyte capsule is the first evidence of a reproductive structure in a Devonian liverwort. Metzgeriothallus sharonae sp. nov. is the oldest known liverwort. The age of the new species helps recalibrate chloroplast DNA studies that have led to proposals of the timing of liverwort diversification by showing that the evolutionary separations of the Jungermanniopsida and Marchantiopsida and of the Metzgeriidae and Jungermanniidae [previously thought to be Late Devonian and Late Carboniferous, respectively] were no younger than late Middle Devonian.  相似文献   

4.
Middle Devonian chitinozoans were studied from 13 deep wells in the central part of the Amazonas Basin, northern Brazil, and compared with a newly established regional miospore zonation. Of the 23 chitinozoan species encountered, four are newly described: Ancyrochitina multibrachiata, Lagenochitina praeavelinoi, Ramochitina autasmirimense, and Ramochitina herculesi and seven species are retained in open nomenclature because of an insufficient number of well-preserved specimens. The stratigraphic intervals investigated herein correspond to three miospore interval range zones previously defined for the Amazonas Basin, namely, the Grandispora/Samarisporites spp. (GS); late Emsian-early Eifelian, Grandispora permulta (Per); late early Eifelian through the Eifelian-Givetian transition, and Geminospora lemurata-Chelinospora ex. gr. ligurata (LLi); early Givetian. A regional Middle Devonian chitinozoan biozonation, also consisting of three zones, is proposed for the investigated interval. These zones are the interval zone of Angochitina n. sp. A (early Eifelian), the interval zone of Alpenachitina eisenacki (late early to late Eifelian), and the total range zone of Ramochitina stiphrospinata (early Givetian).  相似文献   

5.
Samples were collected from southern, central and eastern regions of Saudi Arabia using Malaise traps and sweep nets. Nine species of Tabanidae were identified, two for the first time from Saudi Arabia, Hybomitra peculiaris (Szilády) and Atylotus pulchellus (Loew).Therefore, the total number of Tabanidae in Saudi Arabia is 31 species. Remarks of the species recorded in this study were given. A key to the genera of Tabanidae occurring in the Arabian Peninsula is also provided. Available literature for Saudi Arabian Tabanidae is summarized and provided. It is concluded that the tabanid fauna of Saudi Arabia is more similar to that of the Palaearctic region than to the Afrotropical region.  相似文献   

6.
Well-preserved Early Devonian continental and sparse marine palynomorph assemblages recovered from an exploration borehole located in northern Saudi Arabia are reported here and add to the understanding of Arabian Devonian stratigraphy. The units examined are the conventionally cored lower Murayr, upper Hammamiyat and Sha’iba Members of the Jauf Formation. A comparison with data sets from elsewhere on the Arabian Plate suggests that the units examined are Emsian in age. The age of the Murayr and Hammamiyat boundary interval is revised, based on the occurrence of Dibolisporites eifeliensis in northern Saudi Arabia, and placed in the Rhabdosporites minutus (Min) Interval Zone of the Emphanisporites foveolatus-Verrucosisporites dubia (FD) Oppel Zone. A new miospore, Apiculiretusispora densa with distinctive interradial thickenings, is described.  相似文献   

7.
Svalbardia banksii sp. nov., is described from the Upper Devonian (Frasnian) Fish Cabin Creek locality near Pond Eddy, New York. The compression consists of ultimate branches bearing spirally arranged, unwebbed leaves. The unwebbed leaves are up to 3.2 cm long, are somewhat flexuous, and dichotomize in more than one plane. The new species is similar to the reconstruction of Actinoxylon banksii from the Middle Devonian (Givetian) of New York and strengthens the supposed relationship between Svalbardia polymorpha and Actinopodium nathorstii from Mimerdalen, Spitzbergen.  相似文献   

8.
New bryozoans Saffordotaxis altaicus sp. nov. from the Givetian Stage (Middle Devonian) and Cyphotrypa olgae sp. nov. and Crustopora aliena sp. nov. from the Famennian Stage (Upper Devonian) are described from the Devonian of Gorny Altai.  相似文献   

9.
Ten species of trilobites belonging to 4 genera of the sub-family Asteropyginae DELO are described from the Devonian (Givetian-Frasnian) of Iran. Three of which are new: Neocalmonia lutensis nov. sp., Neocalmonia yazdii nov. sp. and Radiopyge sardarensis nov. sp. The study of this material have required the revision of Heliopyge sharudensis(PILLET, 1974) from the Givetian of the Eastern Alborz Mountains and of Neocalmonia quadricosta PILLET, 1969, type-species of the genus Neocalmonia, from the Frasnian of Afghanistan. The recognition of genera and species in common with the Givetian and the Frasnian of Afghanistan emphasizes the close relations between these two regions. The genera Bradocryphaeus, Heliopyge, Neocalmonia, Radiopyge, represented by related species, are likewise present in Iran, Afghanistan and Western Europe. Their presence confirms that these regions belong, during the Devonian, to the North Gondwanian domain.  相似文献   

10.
A new genus and species of rhabdomesine cryptostome bryozoan, Lunostoma pulchra n. gen. n. sp., is described from the Lower Givetian (Middle Devonian) of the Eifel, Germany. It differs from all previously known rhabdomesines in having crescent-shaped structures (??scuta??) on the proximal sides of the apertures. These scuta resemble the lunaria that characterise cystoporate bryozoans, providing yet another example of homeomorphy in the Bryozoa. The function of scuta is unclear as, in contrast to lunaria, they do not project sufficiently from the apertures to constrain the everting lophophores.  相似文献   

11.
Rhazya stricta Decne is an important medicinal species used in indigenous medicinal herbal drugs to cure various diseases in South Asia (Pakistan, India and Afghanistan) and in the Middle East (e.g. Saudi Arabia, Qatar, United Arab Emirates (UAE), Iran and Iraq). Some of its alkaloids have been reported to have anticancerous properties. The aim of our study is to examine the morphological and taxonomical parameters for R. stricta in the Saudi Arabia; concentrations and distributions of some secondary metabolites; and also to determine the antioxidant and free radical scavenging activity. The results of present study showed that there was no influence of environment on the structure of stomata and trichomes as studying species with R. stricta. In conclusion our study shows no trichomes on leaf of R. stricta it is glabrous, whereas, variations between many secondary metabolites such as flavonoids and phenolic compounds occurred in response to changing climatic conditions.  相似文献   

12.
Stringocephalid brachiopods are widely known in the Givetian, but little knowledge is obtained concerning their palaeobiogeographical patterns globally, therefore further studies with new updates and details are required. In this paper, we describe two new stringocephalid brachiopod genera: Yangirostra asiatica n. gen. n. sp. (subfamily Stringocephalinae) and Chinellirostra rara n. gen. n. sp. (subfamily Bornhardtininae), and a new species Stringocephalus sinensis n. sp., together with an indeterminate species Parastringocephalus sp., from the Givetian (late Middle Devonian) of eastern Yunnan, Southwest China. Moreover, with information of the stringocephalides from North Africa, Alaska, North America, Europe and Northeast Eurasia, we compile a dataset of family Stringocephalidae containing 32 genera in 7 subfamilies globally. Based on our data, subfamily Stringocephalinae brachiopods show cosmopolitism and considerably wide distribution from Siberia to the northern Gondwana margins (i.e., North Africa and Australia). Nevertheless, the Boreal Realm and Palaeotethyan Realm are depicted in this paper at the subfamily level, which is much different from the previous palaeobiogeographical schemes in the Givetian. Furthermore, palaeobiogeographical links between Siberia, the Urals and western North America (Alaska, Canada, Nevada and Sonora) are confirmed by diversification of the subfamilies Omoloninae and Rensselandiinae. Whereas in Eurasia (i.e., western and eastern Europe, North and South China), many endemic species of the subfamilies Bornhardtininae and Geranocephalinae are present, as well as the Kaplexinae and Leioseptathyridinae.  相似文献   

13.
乔丽 《古生物学报》2011,(2):166-175
统计广西中泥盆世不同沉积相区二十条剖面的腕足动物化石记录共计13目45科69属167种,其中Eifelian期47属73种,Givetian期32属100种.对不同级别分类单元的多样性分析表明,从Eifelian期到Givetian期,不仅腕足动物各个目的组成及多样性结构有明显改变,而且各个时期不同沉积环境下的腕足动物...  相似文献   

14.
The stratigraphic levels most favoured for the Middle-Upper Devonian boundary fall approximately within the range of the ammonoid Pharciceras lunulicosta Zone, i.e. from the Middle varcus Subzone to the base of the Lower asymmetricus Zone of the conodont scale. Spore data that are potentially useful for recognition of the boundary within this range have been correlated with conodont zones in marine facies in the Boulonnais region of France. A vast amount of information on spores from Middle-Upper Devonian boundary strata has accumulated in the European U.S.S.R., where the boundary is taken at a somewhat lower level. Late Givetian and early Frasnian continental strata of Melville Island in the Canadian Arctic contain species present in the Boulonnais or the European U.S.S.R., as well as species common to both regions. Diatomozonotriletes spp., Rhabdosporites langii, Samarisporites triangulatus, Contagisporites optivus, Archaeoperisaccus timanicus, Chelinospora concinna and Ancyrospora langii, among others, may be useful for correlating the boundary as eventually defined. The stratigraphic ranges of most of these taxa show only limited agreement interregionally at present, probably owing at least in part to problems of spore nomenclature and taxonomy, and an insufficiency of spore reference sequences keyed to faunal zones. Nevertheless, individual species of spores, and especially assemblages of species, have much potential for delimiting and correlating the Middle-Upper Devonian boundary in both marine and continental facies.  相似文献   

15.
This study was conducted to investigate phytophagous and predatory mites associated with vegetable plants in Riyadh, Saudi Arabia. Eight phytophagous and 10 predacious mites were collected from 14 species of vegetable crops covering five major production localities. Out of these 18 mite species, 13 species are new to the mite fauna of Saudi Arabia. In addition, the two species, Tenuipalpus punicae and Agistemus exsertus, are reported for the first time on vegetable crops in Saudi Arabia. For each mite species found, notes on host plant association and occurrence period are given. An illustrated key for the identification of the 18 mite species reported in this study is provided and this can be used to improve the IPM programs by applying the local natural predatory mites in controlling mite pests in Saudi Arabia.  相似文献   

16.
The deciduous habit and tendency to produce flowers prior to developing leaves, and a predominantly dioecious system of breeding in the genus Commiphora leads to difficulties in its taxonomic identification at species level. The characteristics of easy amplification by universal primer, shorter length and higher discrimination power at the species level makes the internal transcribed spacer (ITS) sequence of nuclear ribosomal DNA (nrDNA) to a smart gene for generating species-specific phylogenetic inferences in most of the plants groups. The present study deals the ITS sequence of nrDNA based molecular genotyping of seven species of the genus Commiphora of Saudi Arabia. The molecular phylogenetic analysis of ITS sequences of nrDNA of Commiphora species distributed in Saudi Arabia reveals the the occurrence of C. madagascariens in Saudi Arabia.  相似文献   

17.
The study of Chonetacean Brachiopods from Cantabrian Mountains allows to recognize several new taxa restricted to this area. A new genus and seven species of which six are new, are described in this paper; their vertical distribution is from Gedinnian to Upper Givetian: Chonetes bediae n. sp., Chonetes? kerforneiRenaud, 1942, Plebejochonetes coliensis n. sp., Plebejochonetes moniellensis n. sp., Luanquella cantabriensis n. g., n. sp., Plicanoplia sotoi n. sp. et Longispina truyolsi. n. sp. The species kerfornei, from the Middle Devonian of Armorican Massif is cited here for the first time from Spain.  相似文献   

18.
This study surveyed 205 wetland sites in the Southwestern Saudi Arabia. We found seven species of amphibians (Anura), which belong to four families: Bufonidae; which includes four species, Sclerophrys tihamica; S. Arabica, Duttaphrynus dhufarensis, and Bufotes viridis; Hylidae, represented by only one species, the tree frog Hyla savignyi; Ranidae, which represented by one species, Pelophylax ridibundus and finally the Dicroglossidae, represented by one species, Euphlyctis ehrenbergii. The reasonable amount of rain received in southwest Arabia, and habitat diversity contribute to the relative abundance of amphibians in the region. Five types of wetland habitats were found in the study area. Valley streams, irrigated farms, seasonal ponds, dam reservoir and lagoons of treated sewage water. The current study revealed the wide spread of amphibians in southwestern Saudi Arabia than what had been reported earlier and confirmed the presence of the Bufotes viridis at three new sites in Asir Heights. It also showed the wide spread of S. arabica in all types of habitats in the southwestern region of Saudi Arabia. Habitat degradation was evident in the region, which might lead to species loss.  相似文献   

19.
A collection of snakes in Turaif region, Kingdom of Saudi Arabia, an area that has been poorly documented for reptiles, consists of 28 specimens representing 11 species belonging to 4 families (Colubridae, Elapidae, Viperidae and Atractaspididae). This study presents the first comprehensive inventory of the herpetofauna of the Turaif province of Saudi Arabia. Co-ordinates: Latitude, longitude and altitude, of the collected specimens were mapped using GPS. Three of the snake species Lytorhynchus diadema, Pseudocerastes fieldi and Walterinnesia morgani reported by the authors in the present survey proved to be new records for Turaif region of Saudi Arabia.  相似文献   

20.
《Mammalian Biology》2014,79(6):409-413
This work represents the most extensive genetic study of the grey wolf (Canis lupus Linnaeus, 1758) in Arabia and the first considering genetic data from multiple locations within Saudi Arabia. Previous suggestion of the occurrence of two subspecies of wolves in Arabia is not supported by this study. The genetic evidence suggests that the wolves of Saudi Arabia are genetically variable and more closely related to the Eurasian wolf Canis lupus group (dog included) than to the Indian wolf C. l. pallipes. The genetic diversity observed for C. lupus in Saudi Arabia indicates that the subspecific status C. l. arabs should be retained for the Arabian wolf. What remains unclear is the degree to which genetic introgression from domestic dogs has influenced the composition and integrity of C. lupus in Saudi Arabia.  相似文献   

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