首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
A new genus of Late Cretaceous radiolarians, Cyprodictyomitra gen. nov., comprising two new species, C. longa sp. nov., C. elegantissima sp. nov., and a new species, Pseudodictyomitra crassa sp. nov. are described. These new taxa come from rich Coniacian-Santonian radiolarian associations of the Perapedhi Formation of Southern Cyprus.  相似文献   

2.
Two new species of Sphenobaiera from the Baisa locality and Chernovskoe coal mine (Lower Cretaceous, Transbaikalia) are described. The cuticle of these plants inhabiting different environments differs significantly. Leaves of S. starukhiniae sp. nov. have a very thin cuticle, almost not sunken, open, nonprotected stomata, while the leaves of S. vitimica sp. nov. have relatively thick and strong cuticle, well-developed papillae overhang the sunken stomata. Guard cells of both species usually have fine radial striations. Apparently, the first plant dwelt in wet habitats, and the second, in the areas with a temporary shortage of water. This reconstruction is confirmed by sedimentological data, coal-bearing sediments (where S. starukhiniae sp. nov. was found) formed in swampy areas, carbonate deposits (S. vitimica sp. nov. was collected in marls of the Baisa locality), in the droughty one. It is not improbable that the cuticular features revealed of these two species contributed to more efficient water exchange and allowed plants to exist in these different environments.  相似文献   

3.
The monotonous cordaitalean leaves are usually difficult to determine as leaf shape and venation can be similar in many species. Therefore cuticular analysis is an important method for distinguishing cordaitalean leaves. Pennsylvanian Cordaites schatzlarensis nov. sp. comes from the ?aclé? locality in the Intrasudetic Basin, Czech Republic. It has been found in mudstone accompanying the upper coal seams No. 9 and 10 of the Jan Šverma Coals, Lampertice Member, ?aclé? Formation and are late Duckmantian in age. The leaves of Cordaites schatzlarensis are lanceolate, amphistomatic. Stomata of the adaxial epidermis are scarce, isolated, or in very short stomatal rows. In contrast, the density of stomata on the abaxial cuticle is high and stomata are arranged into single or double stomatal rows. The cuticles of C. schatzlarensis are comparable with the Chinese Upper Permian C. baodeensis Ge. Leaves can be narrow, comparable to French Bolsovian Dorycordaites zeilleri Ledran, or relatively wide. Accompanying big seeds more than 5 cm in diameter are attributed to Samaropsis newberryi (Andrews) Seward. The pith casts Artisia Sternberg were found in sandy channel fill deposits.  相似文献   

4.
A new xeromorphic conifer from the Cretaceous of East China   总被引:1,自引:0,他引:1  
Newly discovered coniferous shoots from the Cretaceous of Nanjing are attributed to the xeromorphic coniferous genus Glenrosa Watson and Fisher, which is found in China as well as in Eurasia for the first time. G. nanjingensis sp. nov. is known from shoots bearing scale-like leaves with thick epidermal cuticle and hypodermis. Stomata are confined to the abaxial surface deeply sunken in stomatal chambers which are filled with papillae. The cuticle, which has been sectioned for TEM, consists of an outer pale amorphous cuticle proper, usually with a peripheral polylamellate zone, and an inner dark cuticular layer containing reticulate fibrillae. G. nanjingensis sp. nov. bears a close resemblance to the type species G. texensis (Fontaine) Watson and Fisher from North America in gross morphology and especially in the characteristic stomatal chambers, but differs in phyllotaxis and in having the hypostomatic leaf with an obtuse apex. G. nanjingensis sp. nov. is believed to have grown near inland marshes or water bodies under hot and arid climates.  相似文献   

5.
Three new species of fossil snipe flies (Insecta, Diptera, Rhagionidae) from the Daohugou Formation of Chifeng City in Nei Monggol Autonomous Region (= Inner Mongolia), northeastern China are described as Palaeobolbomyia sinica nov. sp., Ussatchovia robusta nov. sp. and Ussatchovia gracilenta nov. sp. They represent the first records of the genera Palaeobolbomyia Kovalev and Ussatchovia Kovalev in China and have implications for stratigraphic correlation of the formations in which they are found. Although the precise age of the Daohugou Formation is currently unresolved, it is most likely Callovian-Oxfordian (latest Middle Jurassic-earliest Late Jurassic) rather than early Middle Jurassic (late Aalenian-early Bajocian) or Early Cretaceous.  相似文献   

6.
Two new species of fossil snipe flies (Rhagionidae) from the Daohugou Formation of Chifeng City in Inner Mongolia Autonomous Region (northeastern China) are described as Palaeoarthroteles jurassicus nov. sp. and P. pallidius nov. sp. They are the first record of the genus Palaeoarthroteles Kovalev and Mostovski beyond Siberia, which have implications for stratigraphic correlation of the formations in which they are found.  相似文献   

7.
A new species, Phoenicopsis anadyrensis Nosova, is described based on the leaf morphology and cuticle features from the Maastrichtian–Danian Rarytkin Formation, Chukotka, North-East of Russia. It is characterized by hypostomatic leaves with stomatal bands on the abaxial side, undulate anticlinal epidermal cell walls and papillae on the epidermal cells and on the subsidiary cells of the stomata. The new species is the youngest reliable representative of the genus Phoenicopsis. This record extends the stratigraphic range of Phoenicopsis from its previously known latest records in the early Campanian up to Maastrichtian–Danian. The persistence of the genus Phoenicopsis up to the Cretaceous–Paleogene boundary is most likely related with vicinity to mountain floras associated with Late Cretaceous and Paleogene volcanic uplands.  相似文献   

8.
The cheirolepidiaceous conifer Pseudofrenelopsis dalatzensis from the Lower Cretaceous Dalazi Formation, Jilin Province, Northeast China is studied in detail based on abundant material. The gross morphology of vegetative shoots shows a greater variation than previously known. Additional information of microstructure is that the adaxial cuticle from the free part of leaves is also papillate as the abaxial cuticle. The excellent preservation of cuticles allows for the first time in this family to four distinct types of cuticle in ultrastructural level: subsidiary cells, guard cells, epidermal cells with and without papillae. Based on 30 measurements the statistic approach on each type of cell cuticle, i.e. not only the total thickness of the cuticle but also details and proportions of all different layers. A key is provided using a combination of 7 significant ultrastructural characters. These results seem to be very promising for the identity of each taxon within the Cheirolepidiaceae family. The cuticular ultrastructure of this family is characterized by having a cuticle proper A composed of A1 wavy polylamellate layer and A2 granular layer, above the cuticular layer B with B1 fibrillate and B2 granular layers. The importance of ultrastructural characters at different levels of taxonomy and palaeoecology is also discussed.  相似文献   

9.
Comptoniaster adamsi nov. sp. (Asteroidea, Valvatida, Goniasteridae) is described from the middle Cretaceous (Cenomanian-Turonian) Britton Formation of northcentral Texas, USA. The new species provides the focus for an exploratory cladistic analysis of Mesozoic asteroids of the Comptoniaster-Tylasteria Group sensu G. Breton. The systematics of Mesozoic goniasterids has relied heavily on the morphology of marginal ossicles, which generally are the best-preserved elements of the skeleton. Unfortunately, marginal ossicular data are scanty for most species because ossicles tend to be morphologically simple yet varied even within individuals, and few even partially articulated specimens are available to provide more comprehensive information. Further, both plesiomorphy and homeomorphy have been important. Because of limited available data, phylogenetic reconstruction here is preliminary. Nevertheless, a number of taxon groupings recognized in the literature are recovered, and stratigraphic distribution provides some support for results. Data unfortunately are particularly incomplete for species of Comptoniaster, the focus of the study. Comptoniaster adamsi nov. sp. clustered with three other species assigned to the genus, including the type, all Cretaceous in age. Jurassic species of Comptoniaster are more widely distributed in the analysis, perhaps reflecting an early stage in diversification or perhaps suggesting the need for species assignment reassessment, but also reflecting the limited available data.  相似文献   

10.
Five new radiolarian species, Dictyophimus? orbiculiporosus sp. nov., Spongomelissa imperceptusa sp. nov., Theocoronium puncticulatum sp. nov., Pterocyrtidium porrectum sp. nov., and Tripodiscinus corona sp. nov., from the Campanian-Danian diatomites of the Leplinskaya Formation of the northern Ural Mountains are described. They are useful for stratification and correlation of the Upper Cretaceous and Lower Paleogene beds of the Ural Region of Western Siberia.  相似文献   

11.
A new species of Pseudotorellia Florin, Pseudotorellia papillata sp. nov., from the Middle Jurassic of Eastern Mangyshlak (Western Kazakhstan, Tonasha Formation) is described. The main distinction of the new species from the other species of this genus is the relief cutinization of periclinal walls of cells of the lower epidermis, especially within stomatal bands, expressed in prominent cuticular ridges and papillae of irregular shape.  相似文献   

12.
Abstract:  Three new genera and four new species of the extinct mantidfly subfamily Mesomantispinae (Insecta: Neuroptera: Mantispidae) are described from the Lower Cretaceous Yixian Formation of Liaoning and the Middle Jurassic Jiulongshan Formation of Inner Mongolia: Archaeodrepanicus nuddsi gen. et sp. nov., A. acutus gen. et sp. nov., Sinomesomantispa microdentata gen. et sp. nov., (Yixian Formation) and Clavifemora rotundata gen. et sp. nov. (Jiulongshan Formation). The specimens described herein represent the first Mesozoic mantidfly compression fossils to have body parts preserved, including the specialized raptorial forelegs articulated to the prothorax anteriorly, an autapomorphy of the family. These new taxa further confirm the placement of the subfamily Mesomantispinae within the family Mantispidae; however, the monophyly of Mesomantispinae has not been confirmed, and it is likely that it will prove to be paraphyletic.  相似文献   

13.
Abstract: Four well‐preserved beetles, attributed to Eodromeinae within Trachypachidae, are described from the Mesozoic of Inner Mongolia, China. Eodromeus robustus sp. nov., E. daohugouensis sp. nov. and Unda chifengensis sp. nov. are from the Middle Jurassic of Daohugou. The diagnostic characters for the two genera are revised, and all species of these genera are keyed. A new genus and species, Sinodromeus liutiaogouensis gen. nov., sp. nov., is described from the Lower Cretaceous Yixian Formation of Liutiaogou. The current fossil records of Trachypachidae from China are reviewed, and only five species (four described here) can be convincingly attributed to this family. The morphological disparity of Mesozoic Eodromeinae suggests that they evolved a broad spectrum of locomotory lifestyles.  相似文献   

14.
The Late Tremadoc storm-dominated shoreface to inner platform deposits exposed west of the Purmamarca village (Coquena Formation) contain a considerably more diverse brachiopod fauna than previously reported. Coquinite horizons from the lower heterolitic succession have yielded monospecific associations of Nanorthis purmamarcaensis nov. sp. (formerly assigned to N. christianiae KJERULF), which is also reported from the Late Tremadoc rocks of the Cerro San Bernardo area. The fine-grained Upper Member of the Coquena Formation contains a more diverse fauna composed by Nanorthis brachymyaria nov. sp., Astraborthis quebradensis nov. sp. and the new plectorthid genus Lipanorthis (type species L. andinus nov. sp.). A different species of Lipanorthis (L. santalaurae nov. sp.) from the Mid Tremadoc Floresta Formation of the Sierra de Mojotoro is also described.  相似文献   

15.
A distinct large vole lineage involving three species from the Late Pliocene - Early Pleistocene of China is morphologically and quantitatively delineated. A special sinuous line (linea sinuosa) pattern, not previously recognized, diagnoses the new lineage, and distinguishes the species in the lineage from all other vole genera known either from China or elsewhere. At present, only two morphologically discrete evolutionary stages can be recognized in the lineage. The primitive stage is represented by rooted Mimomys peii and M. banchiaonicus, and the advanced stage is represented by the newly described rootless Heteromimomys zhengi nov. gen., nov. sp. from the Paleolithic site of Renzidong Cave in Anhui Province. The schmelzmuster of M. peii and Heteromimomys zhengi nov. gen., nov. sp. is also examined to provide more details about the lineage. This lineage diverged from Mimomys by the Late Pliocene within North China. The comparison between the arvicoline species co-existing with Heteromimomys zhengi nov. gen., nov. sp. and those from Haiyan Formation in the Yushe Basin, Shanxi Province, suggests the age of Heteromimomys zhengi nov. gen., nov. sp. can be correlated to or predate the Haiyan Formation, which is in reversely magnetized sediment identified as Chron 2r. The loss of roots in the lineage corresponds with a cooling event at the beginning of the Pleistocene, and seems to characterize the Nihewanian age of the Chinese Land Mammal ages from the perspective of arvicoline biochronology.  相似文献   

16.
Abstract: Several new taxa of snakeflies (Raphidioptera) are described from the Lower Cretaceous deposits of the Wealden, UK (Barremian), Montsec, Spain (Barremian) and the Crato Formation, Brazil (Aptian). Mesoraphidia ednae sp. nov. and M. hilli sp. nov. are described from the Wealden; Nanoraphidia lithographica sp. nov. and Iberoraphidia dividua gen. et sp. nov. are described from Montsec, and Baissoptera lisae sp. nov. is described from the Crato Formation. The geographical range of Nanoraphidia has potentially been extended.  相似文献   

17.
A new genus and two new species of jewel beetles are described, Andakhudukia ponomarenkoi gen. et sp. nov. from the Lower Cretaceous of Mongolia and Metabuprestium ustkivdense sp. nov. from the lowermost Paleogene of the Amur Region. In addition, four new monotypic genera that share some features with jewel beetles are described: Cretoelaterium kazanovense gen. et sp. nov. from the Lower Cretaceous of Eastern Transbaikalia and Cretopoena gratshevi gen. et sp. nov. from the Lower Cretaceous of Mongolia have been referred to the families Elateridae and Eucnemidae; Cretofalselaterium baiankhongoricum gen. et sp. nov. from the Lower Cretaceous of Mongolia and Cretogermen turonicum gen. et sp. nov. from the Upper Cretaceous of Kazakhstan have been erected for isolated elytra and placed in Coleoptera incertae sedis.  相似文献   

18.
Three species of coniferous woods,Araucarioxylon kiiense Ogura,Dadoxylon (Araucarioxylon) japonicum Shimakura andMesembrioxylon chichibuense sp. nov., were first described from the Lower Cretaceous Sebayashi Formation in the Kwanto Mountains.  相似文献   

19.
We describe the new agglutinated foraminiferal genus and species Rectogerochammina eugubina nov. gen., nov. sp. from the Upper Cretaceous Scaglia Rossa Formation of the Umbria-Marche Basin in Italy. The genus differs from Gerochammina (Neagu, 1990) in the presence of a terminal uniserial part.  相似文献   

20.
Rich radiolarian associations are investigated. They include nine new species from the Upper Cretaceous (Coniacian-Santonian) metal-bearing beds of the Perapedhia Formation of southern Cyprus: Dorypyle concinna sp. nov., Gongylothorax mangaleniensis sp. nov., Heliocryptocapsa macroporus sp. nov., H. perapediensis sp. nov., Mita guttiformis sp. nov., Pseudoeucyrtis belogorskensis sp. nov., P. cypricus sp. nov., Rhopalosyringium mangaleniense sp. nov., and Sandovalella trihedra sp. nov.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号