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1.
Triassic radiolarians from Kotel’nyi Island (New Siberian Islands, Arctic Region) are studied. Radiolarians occur in the Middle and Upper Triassic beds, which are well dated by ammonoids, nautiloids, and bivalves. In the Middle Triassic beds, which are composed of dark gray and black clays and claystones with interbeds of combustible schist, siltstone, clayey limestone, and many phosphatic concretions, the following two assemblages are recognized: (1) a Late Anisian assemblage, including Glomeropyle clavatum Bragin, sp. nov., G. boreale Bragin, G. manihepuaensis Aita, G. insulanum Bragin, sp. nov., Triassospongosphaera multispinosa (Kozur et Mostler), Tetraspongodiscus hibernus Bragin, sp. nov., T. borealis Bragin, sp. nov., Eptingium abditum Bragin, sp. nov., E. manfredi Dumitrica, Spongostephanidium japonicum (Nakaseko et Nishimura), and Ladinocampe vicentinensis Kozur et Mostler; (2) Late Ladinian assemblage, with Muelleritortis firma (Gorican), M. kotelnyensis Bragin, sp. nov., Tiborella nivea Bragin, sp. nov., Pseudostylosphaera goestlingensis (Kozur et Mostler), P. omolonica Bragin, Triassospongosphaera multispinosa (Kozur et Mostler), Sarla cincinnata Bragin, sp. nov., S. obscura Bragin, sp. nov., S. prava Bragin, sp. nov., and Eonapora stiriaca Bragin, sp. nov. The Upper Triassic beds, composed of gray and black clays and claystones with lenses of clayey limestones, with sideritic and phosphatic-calciferous concretions have yielded (1) an Early Carnian assemblage, with Pentactinocarpus colum Bragin, sp. nov., Glomeropyle cuneum Bragin, sp. nov., G. algidum Bragin, sp. nov., G. aculeatum Bragin, sp. nov., Kahlerosphaera isopleura Bragin, sp. nov., Stauracanthocircus folium Bragin, sp. nov., Tetraspongodiscus uncatus Bragin, sp. nov., Poulpus costatus (Kozur et Mostler), Eonapora robusta Kozur et Mostler, Planispinocyrtis kotelnyensis Bragin, sp. nov., Annulotriassocampe baldii (Kozur), and Pseudoeucyrtis annosus Bragin, sp. nov.; (2) a Middle-Late Carnian assemblage with Pseudostylosphaera glabella Bragin, sp. nov., P. gracilis Kozur et Mock, P. voluta Bragin, sp. nov., P. gelida Bragin, sp. nov., Kahlerosphaera unca Bragin, sp. nov., K. aspinosa Kozur et Mock, K. fuscinula Bragin, sp. nov., K. acris Bragin, sp. nov., Capnuchosphaera kuzmichevi Bragin, sp. nov., C. triassica De Wever, C. angusta Bragin, sp. nov., Sarla intorta Bragin, sp. nov., S. compressa Bragin, sp. nov., S. aequipeda Bragin, sp. nov., Betraccium irregulare Bragin, B. kotelnyensis Bragin, sp. nov., Spongotortilispinus carnicus Kozur et Mostler, S. subtilis Bragin, sp. nov., Dumitricasphaera simplex Tekin, D. aberrata Bragin, sp. nov., D. arbustiva Bragin, sp. nov., Zhamojdasphaera epipeda Bragin, sp. nov., Z. proceruspinosa Kozur et Mostler, Vinassaspongus subsphaericus Kozur et Mostler, Palaeosaturnalis triassicus Kozur et Mostler, Paronaella concreta Bragin, sp. nov., P. aquilonia Bragin, sp. nov., Tetraspongodiscus cincinnalis Bragin, sp. nov., Annulotriassocampe baldii (Kozur), Canoptum zetangense Wang et Yang, Whalenella speciosa (Blome), Syringocapsa turgida Blome, Droltus gelidus Bragin, sp. nov., and D. niveus Bragin, sp. nov.; (3) an Early Norian assemblage with Pseudostylosphaera glabella Bragin, sp. nov., P. gelida Bragin, sp. nov., P. voluta Bragin, sp. nov., Kahlerosphaera retunsa Bragin, sp. nov., Capnuchosphaera deweveri Kozur et Mostler, Sarla globosa Bragin, sp. nov., Palaeosaturnalis mocki Kozur et Mostler, Paronaella aquilonia Bragin, sp. nov., Syringocapsa turgida Blome, and Droltus gelidus Bragin, sp. nov.; (4) a Middle Norian assemblage with Sarla globosa Bragin, sp. nov., Sarla sp., Syringocapsa turgida Blome, Canoptum sp., and Laxtorum? sp. The fact that these assemblages include taxa that are recorded more southerly, including paleotropical localities, and support dating based on mollusks, enables the use of these data for Boreal-Tethyan correlation. The greatest similarity to Tethyan associations is observed in the Late Carnian and Early Norian, that is, the periods of the greatest penetration of thermophilic mollusks into this basin. A total of 69 radiolarian species of 3 orders, 18 families, and 29 genera are described; 44 species are newly described; the stratigraphic and geographical ranges of the majority of taxa are improved considerably.  相似文献   

2.
The syllid fauna of three locations in Crete and Israel (eastern Mediterranean Sea) was studied, yielding 82 syllid species, many of which were found for the first time in the respective areas: Seventeen species were recorded for the first time on the Israeli coasts and 20 in Greek waters. Perkinsyllis augeneri (Hartmann-Schröder, 1979) and Prosphaerosyllis chauseyensis Olivier et al., 2011 are new records for the Mediterranean Sea. Detailed information is given on the morphology, ecology and distribution of the species recorded for the first time in the studied areas. In addition, an update on the distribution of the genus Prosphaerosyllis San Martín, 1984 in the Mediterranean is given and an identification key to the Mediterranean species is provided.  相似文献   

3.
Notes on the Poaceae of the Robinson Crusoe (Juan Fernández) Islands, Chile, Brittonia 54: 154–163. 2001.—Poaceae in the Robinson Crusoe (=Juan Fernández) Islands number 53 species in 32 genera, of which 9% of the species are endemic, 9% indigenous, and 81% adventitious. The endemic taxa (and their conservation status) are:Agrostis masafuerana (rare),Chusquea fernandeziana (not endangered),Megalachne berteroana (not endangered),M. masafuerana (not endangered), andPodophorus bromoides (extinct).Megalachne andPodophorus are endemic genera. Comparisons with Poaceae in the Bonin and Volcano Islands, Canary Islands, Galápagos Islands, and Hawaiian Islands show different levels of endemism: number of endemic taxa, respectively, 5, 10, 12, 40; percent specific endemism, 8, 6, 21, 19. No endemic genera occur.Anthoxanthum odoratum, Avena barbata andHordeum murinum are noxious weeds in the Robinson Crusoe Islands. Many adventives are shared among floras of the archipelagos, with the highest ties of Robinson Crusoe being to the Canaries (53% of total Poaceae known in Juan Fernández) and the Hawaiian Islands (47%). Low levels of adventives occur within the Bonin (5%) and Galápagos (7%) Islands. In contrast, there are many endemic genera of Asteraceae in these same archipelagos: Bonin and Volcano Islands (1), Canary Islands (8), Galápagos Islands (5), and Hawaiian Islands (6); percent of specific endemism is also higher (20, 53, 54 and 56, respectively). Hypotheses for greater levels of endemics among oceanic island Asteraceae include more efficient dispersal mechanisms by wind and birds, animal pollination systems that result in greater degrees of geographic populational genetic isolation, and a vascular cambium that offers enhanced growth-form evolutionary opportunities.  相似文献   

4.
5.
The faunas associated with oceanic islands provide exceptional examples with which to examine the dispersal abilities of different taxa and test the relative contribution of selective and neutral processes in evolution. We examine the patterns of recent differentiation and the relative roles of gene flow and selection in genetic and morphological variation in the yellow warbler (Dendroica petechia aureola) from the Galápagos and Cocos Islands. Our analyses suggest aureola diverged from Central American lineages colonizing the Galápagos and Cocos Islands recently, likely less than 300 000 years ago. Within the Galápagos, patterns of genetic variation in microsatellite and mitochondrial markers suggest early stages of diversification. No intra-island patterns of morphological variation were found, even across steep ecological gradients, suggesting that either (i) high levels of gene flow may be homogenizing the effects of selection, (ii) populations may not have had enough time to accumulate the differences in morphological traits, or (iii) yellow warblers show lower levels of 'evolvability' than some other Galápagos species. By examining genetic data and morphological variation, our results provide new insight into the microevolutionary processes driving the patterns of variation.  相似文献   

6.
The effects of ice cover on diet and breeding chronology of Adélie (Pygoscelis adeliae) and chinstrap penguins (P. antarctica) were studied in the colonies located at Point Martin, South Orkney Islands. Reproductive success and diet parameters were measured as described in the CCAMLR Environmental Monitoring Program protocols. It was found that late pack-ice break-off in 1998 resulted in lower reproductive success than in 1999 for chinstrap penguins, while Adélie penguin parameters were rather insensitive. This species has shown to be able to cope with this environmental factor, as suggested by its circumpolar and more southerly range. Significant differences in stomach contents' weights and in the proportion of whole krill were found between ice-covered and open-sea periods within and between years. Foraging trips of both species became longer, resulting in underfeeding of chicks and nest desertion by chinstrap-penguin parents. Simultaneous analysis of reproductive parameters of both species and their diets have proven to be useful in discriminating between variation in reproductive success parameters due to prey accessibility and prey abundance.  相似文献   

7.
Two radiolarian assemblages were recovered from upper Norian strata of the Kotel’nyi Island (Russia); the first assemblage, from the Monotis zabaikalica Subzone (lower part of Upper Norian), is represented by Betraccium inornatum Blome, Dumitricaella (?) parva Sugiyama, Ferresium titulense Blome and 24 other species; the second assemblage, from the Monotis subcircularis Subzone (upper part of Upper Norian), is represented by Crucella sp. cf. C. angulosa Carter, Kahlerosphaera acris Bragin, K. sp. cf. K. parvispinosa Kozur & Mostler, Pseudohagiastrum crassum (Carter) and 11 other species. Both assemblages have common taxa with Upper Norian and Rhaetian radiolarian assemblages of British Columbia and they display clear Boreal features: low taxonomic diversity, abundance of taxa known from high-latitude regions, absence or rare presence of taxa known from low-latitude areas. The presence of early representatives of nassellarian genera Droltus and Parahsuum is very distinctive. Six new species are described: Pseudohagiastrum spinosum nov. sp., Cantalum boreale nov. sp., Plafkerium carteri nov. sp., Droltus guttaeformis nov. sp., Laxtorum blomei nov. sp., L. glacialis nov. sp.  相似文献   

8.
Specific features of morphology and biology of two species of nine-spined sticklebacks??Pungitius sinensis and P. pungitius??dwelling in brackish Lake Bol??shoe (Bol??shoi Shantar Island) have been studied. Differences in the number of dorsal spines, vertebrae, and coloration, as well as the absence of specimens with an intermediate phenotype indicate the reproductive isolation of two species supported by the temporal separation of spawning periods. Species P. pungitius was found in Lake Bol??shoe for the first time.  相似文献   

9.
The Floreana Mockingbird (Mimus trifasciatus) is one of the rarest bird species in the world, with an estimated 550 individuals remaining on two rocky islets off the coast of Floreana, Galápagos, Ecuador, from which the main population was extirpated more than 100 yr ago. Because they have been listed in critical danger of extinction, a plan to reintroduce this species to Floreana has been initiated. Determining the health status of the source mockingbird populations is a top priority within the reintroduction plan. We report the health status, over the course of 4 yr, of 75 Floreana Mockingbirds on Champion Island and 160 Floreana Mockingbirds on Gardner-by-Floreana, based on physical examinations, hematology, hemolysis-hemagglutination assay, exposure to selected infectious disease agents, and ecto- and endoparasite counts. Birds on Gardner-by-Floreana had higher body condition index scores, packed cell volumes, total solids, and lymphocyte counts. Additionally, Gardner-by-Floreana birds had lower heterophil counts, eosinophil counts, and heterophil:lymphocyte ratios. No Chlamydophila psittaci DNA or antibodies to paramyxovirus-I, adenovirus-II, or Mycoplasma gallisepticum were found in any of the mockingbirds tested. Ectoparasites were present on birds from both islands, although species varied between islands. A coccidian species was found in eight of the 45 fecal samples from birds on Gardner-by-Floreana, but none of 33 birds examined from Champion. Birds on Gardner-by-Floreana were classified as healthier than those on Champion based on clinical and laboratory findings. These health data will be analyzed in conjunction with genetics, population structure, and disease presence on Floreana for developing recommendations for the Floreana Mockingbird reintroduction plan.  相似文献   

10.
The possible contribution of pinon (Pinus edulis) seed to the diet of an Anasazi population is investigated using present data on seed productivity and archaeological data on resource use. Annual estimates of total productivity for a 135.7 sq km study area in Montezuma County, Colorado, vary by a factor of 141 in a sample spanning 5 yr. Trees greater than about 25 cm (basal diameter) are usually monoecious and produce significantly more cones per tree but fewer good seeds per cone than smaller, usually dioecious specimens. Archaeological data suggest that piñon seed was a relatively unimportant food item after the initial period of Anasazi colonization of the Dolores River valley about a.D. 600. Use of piñon seed as food was inversely related to degree of agricultural intensification and use of piñon for fuel.  相似文献   

11.
Howlers (genus Alouatta) are widely captured with the use of anesthetic projectiles; however, no capture protocol involving the use of traps has been described to date. In the present study we describe the first efficient capture program for black and gold howlers (Alouatta caraya) using traps, which was implemented on the islands of the upper Paraná River in southern Brazil. We constructed two trap models with either manual or automatic activation (trap A with two entrances and guillotine-type doors; trap B with one entrance and a guillotine-type door). The traps were suspended in the canopy by means of vertical climbing techniques, and were baited regularly and abundantly with bananas and mangoes. We captured 70 howlers (86% using manual activation and 14% using automatic activation) on four different islands. We restrained 41 of these animals and measured their body mass, which averaged 5.30 kg+/-1.79. Given our results, we suggest that the system described in the present study represents an alternative capture program for howlers in areas that have low food diversity and no other mammal species that will compete for the bait, as has been observed in riparian environments, islands, and forest fragments.  相似文献   

12.
13.
New data on the distribution and taxonomy of some Palaearctic species of click-beetles of the subfamily Agrypninae are given. The external morphology and genitalia of the previously unknown females of Compsolacon korotjaevi Gur. and C. agrestis (Vats et Kash.) comb. n. are described. Several taxa are recorded from the following territories for the first time: the genus Eumoeus Cand. from the Palaearctic Region, the species Compsolacon agrestis comb. n. and C. himalayanus Jag. from Afghanistan, Compsolacon turkestanicus (Schw.) from Kyrgyzstan and Afghanistan, Danosoma conspersum (Gyll.) from Kazakhstan, Lacon quadrinodatus Lew. from Russia, and L. unicolor (Cand.) from Iraq. Several Northern Indian species of Agrypnus Esch. are transferred to Compsolacon Rtt., and their systematic positions are briefly discussed: C. agrestis, C. inlustris (Vats et Kash.), C. jacksoni (Vats et Kash.), C. kuluensis (Vats et Kash.), C. maisus (Vats et Kash.), C. planocorpus (Vats et Kash.), C. rameshi (Vats et Kash.), C. repercussus (Vats et Kash.), C. solanensis (Vats et Kash.), C. souslapisus (Vats et Kash.), C. subargillus (Vats et Kash.), C. subfaenum (Vats et Kash.) and C. sublapideus (Vats et Kash.) (all comb. n.). The following new combinations are also established: Compsolacon aequalis (Cand.) comb. n. and Compsolacon brachychaetus (Kollar) comb. n. (both ex Lacon). The following new synonymies are established: Lacon funebris (Sols.) = Adelocera grisea Schw., syn. n.; = Adelocera incompta Kr., syn. n.; Eumoeus murrayi Cand. = Tetralobus quadrifoveatus Vats et Kash., syn. n.  相似文献   

14.
15.
In the last few decades, the frequency of the toxic benthic dinoflagellate Ostreopsis cf. ovata proliferation has increased in the Mediterranean Sea. These blooms are associated with harmful effects on human health and the environment. The present work provides the first long term study on the spatio-temporal distribution of O. cf. ovata in relation to physical parameters in the Gulf of Gabès coastal waters (south-eastern Mediterranean Sea), as well as its morphological, molecular and physiological features. The strains of O. cf. ovata were identified morphologically by light and epifluorescence microscopy. The morphology and the size range of cultured strains were similar to those described regarding O. cf. ovata isolated from the Mediterranean Sea. The ultrastructural analysis of O. cf. ovata cells using the transmission electron microscopy showed the presence of numerous vesicles (VE) containing spirally coiled fibers (SCFs) connected to the mucus canal (CH). The phylogenetic tree based on the internal transcribed spacer region containing the 5.8S rDNA (ITS-5.8S rDNA) revealed that O. cf. ovata strains were placed into the Mediterranean/Atlantic clade. In addition, O. cf. ovata toxicity was evaluated by the mouse bioassay and a dose level  4 × 104 cells was found to be lethal to mice. The examination of the O. cf. ovata occurrence in the Gulf of Gabès at a large temporal scale (1997–2012) revealed a clear seasonal pattern with dominance from midsummer (July) to late autumn (November). Furthermore, a positive correlation was found between the abundance of O. cf. ovata and salinity, whereas no correlation was found as regards temperature. The occurrence of O. cf. ovata was only detected at salinity above 35 and the highest concentrations were observed at 45. Laboratory experiments confirmed such a result and showed that isolated O. cf. ovata strains had optimal growth at salinity ranging between 35 and 45, with its peak at 40.  相似文献   

16.
Heterocotyle capapei n. sp. and Thaumatocotyle tunisiensis n. sp. are described from the gills and the nasal cavity, respectively, of Dasyatis tortonesicollected from the Tunisian coast. H. capapei is distinguished from other species in the genus by the morphology of the penis, which is conical and has a long narrow distal point. T. tunisiensis differs from all known species of Thaumatocotyle by the shape and size of the penis. The host Dasyatis tortonesi has long been confused with D. pastinaca. Our study shows that their monogeneans are oioxenic, suggesting that D. pastinaca and D. tortonesi are distinct species. These results suggest that the monogenean parasite fauna could be used as a diagnostic tool for species identification: these parasites may, therefore, represent good biological indicators. The host-specificity of the Heterocotylinae and Merizocotylinae is discussed.  相似文献   

17.
Estimating population densities of key species is crucial for many conservation programs. Density estimates provide baseline data and enable monitoring of population size. Several different survey methods are available, and the choice of method depends on the species and study aims. Few studies have compared the accuracy and efficiency of different survey methods for large mammals, particularly for primates. Here we compare estimates of density and abundance of Kloss’ gibbons (Hylobates klossii) using two of the most common survey methods: line transect distance sampling and triangulation. Line transect surveys (survey effort: 155.5 km) produced a total of 101 auditory and visual encounters and a density estimate of 5.5 gibbon clusters (groups or subgroups of primate social units)/km2. Triangulation conducted from 12 listening posts during the same period revealed a similar density estimate of 5.0 clusters/km2. Coefficients of variation of cluster density estimates were slightly higher from triangulation (0.24) than from line transects (0.17), resulting in a lack of precision in detecting changes in cluster densities of <66 % for triangulation and <47 % for line transect surveys at the 5 % significance level with a statistical power of 50 %. This case study shows that both methods may provide estimates with similar accuracy but that line transects can result in more precise estimates and allow assessment of other primate species. For a rapid assessment of gibbon density under time and financial constraints, the triangulation method also may be appropriate.  相似文献   

18.
19.
Summary The importance of animals as seed dispersers for Bursera graveolens (Burseraceae) was assessed by analysis of juvenileadult interplant distances on Santa Fe Island, Galápagos. The Santa Fe Bursera population consists of two non-overlapping classes old, large adults, and juveniles recruited since the exermination of feral goats in 1971. Juveniles occurred on a variety of substrate types, as well as under and away from woody vegetation. Most juveniles arise from seeds dispersed by animals; 86% of the juveniles were 3 m away from the crown of the nearest adult, and half were 7 m away. Although all juveniles occurred within 35 m of an adult Bursera, seed dispersal by animals is an important factor in the regeneration of B. graveolens on Santa Fe.  相似文献   

20.
Improvements in biodiversity conservation are hampered by the lack of reporting on the effectiveness of conservation techniques and the organizations that implement them. Here we summarize the accomplishments and potential impact of the non-governmental organization, Island Conservation, which eradicates damaging invasive vertebrates from islands. Island Conservation has removed 54 populations of 10 invasive vertebrates from 35 islands totaling over 520 km2. These actions helped protect 233 populations of 181 insular endemic species and subspecies of plants and vertebrates and 258 populations of 54 species and subspecies of seabirds from the threat of local and global extinction. There were no reinvasions. One eradication attempt failed. These conservation actions and their apparent biodiversity impact demonstrate the potential of private organizations to protect biodiversity by eradicating invasive species from islands.  相似文献   

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