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1.
The discovery in the uppermost Jurassic of Lebanon of a species of the ostracod genus Microceratina Swanson, 1980 (Eucytherurinae), of which the oldest known species was until now of Maastrichtian age, confirms the Tethyan origin of this genus. Two new species are created: Microceratina bhannesensis nov. sp. from the Upper Jurassic (Kimmeridgian) of Lebanon, and Microceratina azazoulensis nov. sp. from the Cenomanian of Morocco. The genera Chapmanicytherura Weaver, 1982 and Erratacytheridea Herrig et al., 1997, are considered as probable junior synonyms of Microceratina. An exhaustive bibliographical analysis allowed to identifying several other Cretaceous species susceptible to be assigned to the genus Microceratina.  相似文献   

2.
Terrestrial actinobacteria have served as a primary source of bioactive compounds; however, a rapid decrease in the discovery of new compounds strongly necessitates new investigational approaches. One approach is the screening of actinobacteria from marine habitats, especially the members of the genus Streptomyces. Presence of this genus in a marine sponge, Haliclona sp., was investigated using culture‐dependent and ‐independent techniques. 16S rRNA gene clone library analysis showed the presence of diverse Streptomyces in the sponge sample. In addition to the dominant genus Streptomyces, members of six different genera were isolated using four different media. Five phylogenetically new strains, each representing a novel species in the genus Streptomyces were also isolated. Polyphasic study suggesting the classification of two of these strains as novel species is presented. Searching the strains for the production of novel compounds and the presence of biosynthetic genes for secondary metabolites revealed seven novel compounds and biosynthetic genes with unique sequences. In these compounds, JBIR‐43 exhibited cytotoxic activity against cancer cell lines. JBIR‐34 and ‐35 were particularly interesting because of their unique chemical skeleton. To our knowledge, this is the first comprehensive study detailing the isolation of actinobacteria from a marine sponge and novel secondary metabolites from these strains.  相似文献   

3.
Microbial communities are linked with marine sponge are diverse in their structure and function. Our understanding of the sponge-associated microbial diversity is limited especially from Red Sea in Saudi Arabia where few species of sponges have been studied. Here we used pyrosequencing to study two marine sponges and coral species sampled from Obhur region from Red sea in Jeddah. A total of 168 operational taxonomic units (OTUs) were identified from Haliclona caerulea, Stylissa carteri and Rhytisma fulvum. Taxonomic identification of tag sequences of 16S ribosomal RNA revealed 6 different bacterial phyla and 9 different classes. A proportion of unclassified reads were was also observed in sponges and coral sample. We found diverse bacterial communities associated with two sponges and a coral sample. Diversity and richness estimates based on OUTs revealed that sponge H. caerulea had significantly high bacterial diversity. The identified OTUs showed unique clustering in three sponge samples as revealed by Principal coordinate analysis (PCoA). Proteobacteria (88–95%) was dominant phyla alonwith Bacteroidetes, Planctomycetes, Cyanobacteria, Firmicutes and Nitrospirae. Seventeen different genera were identified where genus Pseudoalteromonas was dominant in all three samples. This is first study to assess bacterial communities of sponge and coral sample that have never been studied before to unravel their microbial communities using 454-pyrosequencing method.  相似文献   

4.
A new specimen of the widespread Middle Jurassic to Lower Cretaceous Asian gonipholidid crocodilian genus Sunosuchus is described on the basis of a partial skeleton from the Upper Toutunhe Formation (Middle Jurassic, ?Bathonian-Callovian) of Liuhonggou, SW of Urumqi, Xinjiang Uygur Autonomous Region, People’s Republic of China. The specimen is represented by a partial mandible, teeth, vertebrae, limb and girdle bones and osteoderms. It can be distinguished from other nominal species of the genus by a unique combination of characters: slightly heterodontous dentition, strongly sculptured posteroventral part of the mandible, short fenestra mandibularis, convex dorsal surface of the retroarticular process, keeled cervical vertebral centra and ventral osteoderms with a distinctive sculpture of wide pits and narrow ridges. The heterodontous dentition is a potential autapomorphy of this form. The new specimen is closest in morphology to material described recently from the Callovian of Kirghisia as Sunosuchus sp. It represents the second Middle Jurassic record of the genus, the first crocodile from the Toutunhe Formation, the first substantial crocodile find from the Mesozoic of the Southern Junggar Basin, and the first Middle Jurassic record of Sunosuchus from China. This extends both the paleobiogeographical distribution of the genus in Asia and its stratigraphic distribution in China considerably.  相似文献   

5.
The skeleton morphology of the azooxanthellate cold-water coral Lophelia pertusa can be strongly influenced by invasive boring sponges that infest corallites in the still living part of the colony. Atypically swollen corallites of live Lophelia pertusa from the Galway Mound (Belgica Carbonate Mound Province, Porcupine Seabight, NE Atlantic), heavily excavated by boring organisms, have been examined with a wide range of non-destructive and destructive methods: micro-computed tomography, macro- and microscopic observations of the outer coral skeleton, longitudinal and transversal thin sections and SEM analyses of coral skeleton casts. As a result, three excavating sponge species have been distinguished within the coral skeleton: Alectona millari, Spiroxya heteroclita and Aka infesta. Furthermore, four main coral/sponge growth stages have been recognised: (1) cylindrical juvenile corallite/no sponge cavities; (2) flared juvenile corallite/linear sponge cavities (if present); (3) slightly swollen adult corallites/chambered oval sponge cavities; (4) very swollen adult corallites/widespread cavities. The inferred correlation between corallite morphology and boring sponge infestation has been detected in micro-computed tomography (micro-CT) images and confirmed in sponge trace casts and peculiar features of coral skeleton microstructure. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorised users.  相似文献   

6.
A comprehensive outline of the Jurassic ammonoid superfamily Aequiloboidea is here presented: this group is known from? Rhaetian-early Hettangian to early Pliensbachian and it is exclusively found within the Mediterranean Tethys (Austrian Alps, Bavarian Prealps, Tuscany, Umbria-Marche and Abruzzi Apennines, Morocco, Tunisia, western Hungary). On the basis of the available documentation, it is composed by two families (Aequilobidae and Sinuiceratidae), to which five genera belong: Aequilobus Bilotta (previously informally indicated as “genus from Monte Bove”), Dudresnayiceras Rakús, Sinuiceras Venturi and Ferri, and Sphenoacanthites Venturi, Nannarone and Bilotta, plus Xenoloboceras nov. gen., which position at the family level is uncertain. All of them share a peculiar combination of morpho-structural characters, which was never observed in any form referable to known groups. Due to the particularities presented by the Aequiloboidea and to the scarce documentation on the earliest Jurassic in the Mediterranean regions, it is currently impossible to demonstrate that this taxon originated within any of the already-known Jurassic ammonoid orders (Phylloceratida and Psiloceratida). An at least partially independent derivation cannot be excluded, as suggested also by the results of a cladistic analysis.  相似文献   

7.
Gabriel A. Gill 《Geobios》1982,15(2):217-223
Epistreptophyllum, a rather common coral in the Middle and Late Jurassic of Europe and Asia, is generally regarded as solitary. Some specimens collected in Late Callovian beds of the northern Negev, Israel, show genuine branching which would suggest a colonial habit for this genus. Eventual convergence between the genera Epistreptophyllum, Haplaraea and Diplaraea is presumed.  相似文献   

8.
Yanliaoa is a common fossil in the Middle Jurassic of western Liaoning, eastern Inner Mongolia and northern Hebei Province, China. It is an important element of the Yanliao biota. The genus was established by Pan in 1977 for fossil plants from the Middle Jurassic Haifanggou Formation in Xiasanjiaochengzi, western Liaoning Province, and in present paper, the genus Yanliaoa is studied based on new material. Pan never designated a type specimen and his fossil material cannot be located. We designate a type specimen here for Yanliaoa, so that the genus name Yanliaoa remains valid. Yanliaoa sinensis Pan emend. Tan et al., is found in the same locality and formation as the lost specimens, Y. sinensis of Pan, 1977. Yanliaoa daohugouensis n. sp., a new species with epidermal anatomy, is from the Middle Jurassic Daohugou, Inner Mongolia. A holotype is also selected from the new material for this new species. Characters of the leafy shoots and ovulate cones of Yanliaoa are emended. The epidermal anatomy of this genus is described for the first time. Compared with other extant and extinct species of Cupressaceae s. l., the current species can be distinguished from any known species both by the leafy shoot characters and its epidermal anatomy. It further indicates that Yanliaoa is an extinct and endemic conifer found in the Middle Jurassic of northeastern China.  相似文献   

9.
《Palaeoworld》2021,30(3):461-494
The paper describes new Lower Jurassic corals from the South-Eastern Pamir Mountains (Tajikistan) and interprets their relationships with contemporaneous West Tethyan corals. Taxonomic similarities with Pliensbachian European and North African faunas indicate a Pliensbachian age for this fauna, which was previously considered to be of Hettangian/Sinemurian age. Together with the taxa earlier described from the Pamirs, this fauna consists of 30 species of 25 genera, including Triassic holdover genera such as Stylophyllopsis, Phacelostylophyllum and Eocomoseris. The bulk of the fauna represents new Jurassic genera: Alichurastrea, Eomicrophyllia, Guembelastreomorpha, Gurumdynia, Pinacomorpha, Protostephanastrea, Psenophyllia, Sedekastrea and Stylimorpha. Earlier coral studies of the region concerned the genera: Archaeosmilia Melnikova, 1975, Archaeosmiliopsis Melnikova, 1975, Cylismilia Roniewicz, 1988, Pachysmilia Melnikova, 1989, and Prodonacosmilia Melnikova in Melnikova and Roniewicz, 1976. Two species that were considered to belong to the genus Cylismilia, are redescribed and reclassified in the genera Psenophyllia, and Archaeosmilia Melnikova, respectively.  相似文献   

10.
11.
Abstract: A rich coral‐associated decapod assemblage is recorded from the ‘Depiru Beds’ of the upper part of the Upper Coralline Limestone (Messinian, Upper Miocene), from the island of Malta. Nineteen species within 17 genera have been discovered, where 14 genera are new for Malta. Four new species are described, namely Micippa annamariae sp. nov., Pilumnus scaber sp. nov., Panopeus muelleri sp. nov. and Herbstia melitense sp. nov. Herbstia melitense sp. nov. constitutes the first record of the genus from the fossil record in the Mediterranean region. This discovery more than doubles the number of known fossil decapod species from Malta. The fossil bivalve Jouannetia (J.) semicaudata Des Moulins, 1830 and the extant decapod Maja goltziana D’Oliveira, 1888, are also recorded for the first time from Malta. Other Neogene coral‐associated decapod assemblages are investigated and correlated with the new assemblage from Malta. The migration of taxa between the Mediterranean region and the Paratethys, particularly during the Lower Badenian (Langhian), is evidenced by the strong affinity of the Maltese decapod assemblage with that of the Middle Miocene Badenian assemblages from Hungary, Poland and Ukraine. Upper Miocene, Messinian assemblages from Spain, Algeria and Morocco are also similar to that from Malta.  相似文献   

12.
A new genus and species of octocoral with a calcium-carbonate skeleton, Nanipora kamurai sp. n., is described from a shallow coral reef in Okinawa, Japan. Contrary to most octocorals, the skeleton is composed of crystalline aragonite as in blue coral Heliopora. The results of molecular phylogenetic analyses of sequences of mtMutS, COI, and ITS1-5.8s-ITS2-28S region suggest Nanipora gen. n. specimens should be included in order Helioporacea. Based on morphological results compared with other Helioporacea including the genus Epiphaxum (family Lithotelestidae), we establish the new genus Nanipora within Lithotelestidae. This is the first time that a close molecular phylogenetic relationship between Heliopora and a related genus within Helioporacea has been revealed.  相似文献   

13.
A new genus, Heppneralis Park, gen. nov., of the subfamily Torodorinae, is described based on the type species, H. decorella sp. nov., and an additional new species, H. dumogaensis sp. nov., from Is. Sulawesi, Indonesia is described. The new genus is distinguished from all known genera of the subfamily by unique wing color markings on both wings, with R5 and M2 absent in the forewing and M2 absent in the hindwing.  相似文献   

14.
Multiplicatispirifer, a new delthyridoid brachiopod genus with a gently divergent capillate micro-ornamentation and bifurcating costae on flanks, sulcus and fold, has been identified in the Mdâouer-el-Kbîr Formation of the Dra Valley (southern Anti-Atlas, Morocco). Its type speciesMultiplicatispirifer foumzguidensis n. gen., n. sp., at present the only species of this genus, is described. This form has hitherto been determined asFimbrispirifer orStruveina by various authors. In this work, the new genus is compared with the multiplicate and capillate spiriferid genera with bifurcating costae which also have costae in the sulcus and on the fold:Costispirifer andPerryspirifer from North America,Elymospirifer from South China,Borealispirifer from Asia andMultispirifer from Central Europe. The relation ofMultiplicatispirifer to the fimbriateFimbrispirifer, Struveina andVandercammenina, from which it is distinguished by its capillate micro-ornamentation, is discussed. The new genus is hitherto only known from the Moroccan southern Anti-Atlas. Its colsest relatives, taxa ofCostispirifer, occur in the Eastern American Realm (Gaspé, Canada and the eastern United States) and the Nevada Province (western United States).Multiplicatispirifer occurrences are restricted to the Lower/Upper Emsian boundary interval (upper Lower Devonian). The reasons for a possible migration corridor between North America and North Africa before Emsian time are discussed.  相似文献   

15.
Recent pharetronid sponges were regarded as relict species in tropical and subtropical waters, inhabiting cryptic habitats on coral reefs and in caves. More recent findings of a new species of the genus Plectroninia off northern Norway, with an inner fused skeleton have changed that view. Recent investigations on the sponge fauna of the “Propeller Mound”, northern Porcupine Seabight, focusing on sponges growing on the azooxanthellate cold-water coral Lophelia pertusa (Linné 1758) and Madrepora oculata Linné 1758, established the presence of a species of Plectroninia new to science. Its status as a common species within this deep-water coral habitat and the general status of the genus Plectroninia are discussed.  相似文献   

16.
Interactions between organisms add complexity to ecosystem function, particularly on coral reefs. The Caribbean orange icing sponge Mycale laevis is semi-cryptic, often growing under coral colonies or between coral branches. This association is reportedly a mutualism, with the sponge deterring boring sponges from invading the coral skeleton and the coral providing an expanding surface for sponge growth. But is there an alternative explanation for the proximity of sponge and coral? We examined the importance of fish predation on the growth of the sponge. While the semi-cryptic growth form of M. laevis predominates on reefs off the Florida Keys and the Bahamas Islands, M. laevis grows with a non-cryptic, erect morphology off Bocas del Toro, Panama. Surveys revealed that sponge-eating fishes were rare or absent at Bocas del Toro compared to sites in the Florida Keys. Because past studies were inconsistent about the palatability of M. laevis to fish predators, we conducted feeding experiments with sponges from all three sites. Crude organic extracts of M. laevis from all three sites were palatable to generalist fish predators in aquarium assays, and field feeding assays and caging experiments conducted in the Florida Keys confirmed that spongivorous fishes readily ate exposed fragments of M. laevis. Our results suggest that M. laevis is restricted to its semi-cryptic growth form by spongivorous predators, with corals providing a physical refuge from predation. This alternative explanation supports the broader hypothesis that Caribbean reef sponges can be categorized on the basis of chemical defense into defended, palatable, and preferred species, the last of which are restricted to refugia.  相似文献   

17.
The new damsel-dragonflies Zygokaratawia incompleta nov. sp. and Parazygokaratawia azari nov. gen., nov. sp., closely related to the campterophlebiid genus Zygokaratawia, are described from the Middle Jurassic locality of the Daohugou and Chentaizi villages, respectively (Ningcheng County, Inner Mongolia, NE China). Parazygokaratawia nov. gen. and Zygokaratawia share a narrowly reduced cubito-anal area, unique synapomorphy in the Isophlebioptera. Campterophlebiids with this character are only known from the Daohugou biota.  相似文献   

18.
Ocean acidification is widely accepted as a primary threat to coral reef populations. Negative physiological effects include decreased calcification rates, heightened metabolic energy expenditure, and increased dissolution of coral skeletons. However, studies on the dissolution of coral skeletons structures under ocean acidification conditions and their implications on sediments remain scarce. In this work, we examined skeletal dissolution kinetics from four of the most representative hermatypic corals of the Eastern Pacific coasts (Pocillopora, Porites, Pavona, and Psammocora). Samples were treated with a highly acidic solution for defined periods of time, and measurements of dissolved calcium ([Ca+2]) were used to evaluate the kinetics of coral skeleton dissolution. All genera tests except Porites showed a zero reaction rate. Porites exhibited a first-order reaction and a faster reaction rate than other genera. Compression strength tests and skeletal density did not correlate with reaction rate. Pavona showed greater structural strength. Porites were the most susceptible to acidic dissolution compared to other genera tested due to their morphology, i.e., possession of the largest surface area, suggesting a high vulnerability under low-pH conditions. The hierarchical response in dissolution kinetics among coral genera tested suggests that the most soluble coral might act as a buffer under ocean acidification conditions.  相似文献   

19.
Whereas Middle Jurassic gastropods are very well known in Europe and other regions of the world, these faunas have been much less studied from northern Africa and most contributions available in literature have been based on relatively well-preserved material. Except a little lower Bajocian fauna from the Central High Atlas (Morocco) described at the turn of the 21th century, nothing is known about the Middle Jurassic gastropods of the southwestern Tethyan margin. The present paper aims to update the systematics of two vetigastropod species: Obornella cf. granulata (Sowerby, 1818) and Ambercyclus ornatus (Sowerby, 1819) recently found in the upper Bajocian succession of the Ksour Mountains (Tniet el Klakh Formation) at western Saharan Atlas (northern Algeria). The new Ambercyclus material found in well-preserved conditions confirms the absence of umbilicus in Ambercyclus; thus, we emend the original generic diagnosis. The specimens of Obornella cf. granulata and Ambercyclus ornatus represent the first occurrence of both genera and species in the upper Bajocian marine deposits of the western Saharan Atlas, and provide new taxonomic and palaeobiogeographic information about Middle Jurassic vetigastropods in Algeria.  相似文献   

20.
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