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1.
John A. Raven 《Plant Ecology & Diversity》2013,6(3):477-485
Summary The life cycle of the Batrachospermales (freshwater florideophyte red such as Batrachospermum, Lemanea) is a shortened variant of the ‘normal’ marine florideophyte life cycle. The perennial Chantransia diploid phase is microscopic and encrusting. Each winter it produces one or more semi-erect haploid gametophytes by vegetative meiosis. Gamete production and fertilization is followed by production of diploid carposporophytes; these produce diploid carpospores which disperse, and regenerate the Chantransia phase. The question of the extent to which the Chantransia phase contributes resources to the gametophyte was approached by physiological-hydrodynamic modelling. These computations suggest that the photosynthetic rates in situ on an area basis are 20 times greater for the gametophyte than the Chantransia phase; this agrees with the observed ratios of peak biomass. The conclusion is that the Chantransia phase has a negligible role in provisioning the growing gametophyte, and that the role of the Chantransia phase is to occupy space with living biomass throughout the year, including exposure at summer drawdown, and (perhaps) by dispersal via production of monospores. A similar conclusion is arrived at on the basis of biomass data for the role of the perennial ‘mushroom’ phase of the semelparous marine Fucalean brown alga Himanthalia elongata in relation to the short-lived but much larger reproductive receptacles. 相似文献
2.
The male of Brumptomyia angelae, sp. nov., a new species of Phlebotominae (Diptera, Psychodidae) of the Atlantic forest of the state of Paraná, Brazil, is described and illustrated. This new taxon is closely related to Brumptomyia ortizi Martins, Silva & Falc?o 1971, Brumptomyia nitzulescui (Costa Lima, 1932), and Brumptomyia troglodytes (Lutz, 1922). The male genitalia of these three latter species have also been drawn. 相似文献
3.
E. A. Streletskaya 《Contemporary Problems of Ecology》2010,3(4):469-480
The zooplankton composition is studied in the thermokarst, glacial and meteorite lakes, channels, former riverbeds, and hollows
in the basin of Anadyr’. We found 174 taxa: 78, Rotatoria, 55, Cladocera, and 41, Copepoda. The most diverse is the lake fauna:
51 taxa of Rotatoria, 48, Cladocera, and 37, Copepoda. The thermokarst Lake Maiorskoe hosts 68 taxa: 31, Rotatoria, 14, Cladocera,
and 23, Copepoda, wheras the cold ultraoligotrophic Lake El’gygytgyn features only one species of Cyclop of the group scutifer Cyclops neymanae Strel., and Rotatoria and Cladocera are present as allochtonous forms. The Copepoda illustrate the relations of the Anadyr’
fauna with those of Europe, North America, and Japan. 相似文献
4.
Valentin Popa Louis Morneau Céline Piché André Deshaies Eric Bauce Claude Guertin 《ZooKeys》2013,(348):97-124
Twig beetles in the genus Pityophthorus Eichhoff, 1864 include more than 300 species worldwide, with maximum diversity in tropical and subtropical regions. To date, approximately 50 species of Pityophthorus have been recorded in Canada, and these species are associated mainly with coniferous trees. Since 1981, no comprehensive study on this difficult taxonomic group has been conducted in Quebec, Canada, most likely due to their limited significance as forest pests. Based on data gathered from five years of field sampling in conifer seed orchards and compiled from various entomological collections, the distribution of Pityophthorus species in Quebec is presented. Approximately 291 new localities were recorded for the Pityophthorus species. Five species-group taxa, namely Pityophthorus puberulus (LeConte, 1868), Pityophthorus pulchellus pulchellus Eichhoff, 1869, Pityophthorus pulicarius (Zimmermann, 1868), Pityophthorus nitidus Swaine, 1917,and Pityophthorus cariniceps LeConte&Horn, 1876 were the most widespread. In contrast, Pityophthorus consimilis LeConte, 1878, Pityophthorus intextus Swaine, 1917, Pityophthorus dentifrons Blackman, 1922, Pityophthorus ramiperda Swaine, 1917, and Pityophthorus concavus Blackman, 1928 display a notably limited distribution. In addition, the first distribution records of Pityophthorus intextus and Pityophthorus biovalis Blackman, 1922 are furnished, and the subspecies Pityophthorus murrayanae murrayanae Blackman, 1922is reported from Quebec for the second time. Moreover, distribution maps are provided for all Pityophthorus species recorded in the province of Quebec. 相似文献
5.
J Moens 《Archives internationales de physiologie et de biochimie》1975,83(3):443-451
The ionic regulation of the haemolymph of larvae of Aeshna cyanea (Müller) was studied by means of two types of experiments. In the first the change in internal ionic composition was followed as a function of the time spent in a given experimental medium. These experiments led to the conclusion that: 1. the haemolymph composition does not change when larvae are starved in tap water for 10 days; 2. the haemolymph ionic concentrations (Na and Cl) have initial marked increase when the animals are kept in hypertonic media of diluted sea water; after 80 hours however, both concentrations stay constant. In a second series of experiments the internal ionic concentration was compared to a series of different concentrations of external media. From this, the relation between the internal and external ionic concentration was elaborated : in hypotonic media the internal Na and Cl concentrations stay constant, in hypertonic media there is a parallelism between the increase of the external concentration and haemolymph concentration, the internal Na concentration being always slightly hypertonic, the Cl concentration markedly hypotonic. Finally, when larvae are placed in glass distilled water, the internal Na and Cl concentrations begin to decrease after 60 hours. 相似文献
6.
Dr. D. R. Nässel 《Cell and tissue research》1975,163(4):445-464
The Lamina ganglionaris (first optic neuropile) of the decapod crustacean Pandalus borealis has its optic cartridges (synaptic compartments) arranged in horizontal rows. Each optic cartridge contains seven receptor axon terminals and the branching axis fibres of five monopolar second order neurons. Four types of monopolar neurons are classified. Their cell bodies are arranged in two layers. The inner layer contains the cell bodies of exclusively one of these types, and each cartridge is invaded by two neurons of this neuron type (type M 1:a and M 1:b). The outer layer contains the cell bodies of the remaining three types (M 2, M3 and M4). One gives rise to a large radially branched axis fibre in the centre of the cartridge. The other two have wide branches which may make inter-cartridge contacts, one proximally and the other distally in the plexiform layer, which is clearly bistratified. The receptor axons terminate in two levels corresponding to these strata. Two sets of tangenital fibres form networks in the proximal and the mid-portion of the lamina. Both networks have fibres with primary branches in the vertical plane and secondary branches in the horizontal plane. The fibres of the networks are derived from axons that pass from the second optic neuropile, the medulla externa. 相似文献
7.
Espíndola EL Matsumura-Tundisi T Rietzler AC Tundisi JG 《Revista brasileira de biologia》2000,60(2):179-194
With the purpose of analyzing the horizontal distribution of the zooplankton community of the Tucuruí Reservoir in the State of Pará, Brazil, collections were made at 16 stations during August 1988. The stations cover the regions called Caraipé (C), Ara?agi (B) and Arar?o (A), and represent the different compartments of this ecosystem in regard to the morphometry and the presence or absence of "flooded forest". Our findings showed the existence of three compartments with different limnological characteristics determined as a function of the system's morphometry, a factor that may have influenced the horizontal circulation of the reservoir's water and, consequently, led to physical, chemical and biological differences at each of the sampled stations. All the stations presented physical and chemical stratification and layers of total anoxia or reduced concentrations of oxygen dissolved at depths corresponding to the limit of the euphotic zone. With regard to the zooplankton, a differentiated distribution that was mainly quantitative was found among the compartments (density of organisms and proportion among the species) in the case of Cladocera and Copepoda, and basically qualitative in the case of Rotifera. On the other hand, the greatest densities of organisms for all the groups were recorded at the Caraipé stations. As for the spatial distribution, some species were more restricted or more abundant at given stations. Among the Cladocera, there was a greater abundance of Moina minuta, Bosmina hagmani and Bosminopsis deitersi at the Ara?agi stations, while C. cornuta intermedia, C. cornuta rigaudi and C. cornuta cornuta were more plentiful in the Caraipé and Diaphanosoma birgei in the Arar?o. Among the Rotifera, Trochosphaera aequatoriales and Lecane proiecta, Ascomorpha ecaudis, besides Polyartha cf vulgaris were restricted, respectively, to the Caraipé, Ara?agi and Arar?o stations, while the others, such as Keratella americana and Collotheca sp., were more broadly distributed. As regards Copepoda Calanoida, the dominating species was found to be Notodiaptomus maracaibenses, followed by Notodiaptomus henseni and Argyrodiaptomus azevedoi. The most abundant Cyclopoda species was Thermocyclops minutus, although Thermocyclops decipiens, Mesocyclops longisetus, Mesocyclops meridianus e Metacyclops sp. were also found. 相似文献
8.
Gy?rgy Makranczy 《ZooKeys》2015,(509):141-146
The previously unknown male of Leptotyphlus
kovaci Šustek, 2000 is described and illustrated. The relationship of the species is discussed. The species is also reported from Gemerskoteplická jaskyňa near Jelšavská Teplica (Slovakia). 相似文献
9.
A new species of Kritskyia inhabits the urinary bladder of the "curimba", Prochilodus lineatus in the floodplain of the high Paraná river. The new species resembles others members of Kritskyia in the following features: haptor lacking anchors and with 14 hooks marginal, posterior male copulatory organ non articulated with the accessory piece and vagina a sclerotized tube. However, it differs from the known species mainly by the shape of the copulatory complex. This is the third endoparasitic monogenean species reported from freshwater Neotropical fish. 相似文献
10.
A critical and annotated catalogue of 183 types of Hymenoptera
Chrysididae belonging to 124 taxa housed in the Radoszkowski collection is given. Radoszkowski type material from other institutes has also been checked. Six lectotypes are designated in Kraków (ISEA-PAN): Chrysis
acceptabilis Radoszkowski, 1891; Chrysis
persica Radoczkowsky, 1881; Chrysis
daphnis Mocsáry, 1889; Chrysis
lagodechii Radoszkowski, 1889; Chrysis
remota Mocsáry, 1889 and Chrysis
vagans Radoszkowski, 1877. The lectotype of Brugmoia
pellucida Radoszkowski, 1877 is designated in Moscow (MMU). Four new combinations are proposed: Philoctetes
araraticus (Radoszkowski, 1890), comb. n.; Pseudomalus
hypocrita (du Buysson, 1893), comb. n.; Chrysis
eldari (Radoszkowski, 1893), comb. n.; and Chrysura
mlokosewitzi (Radoszkowski, 1889), comb. n.. Ten new synonyms are given: Chrysis
auropunctata Mocsáry, 1889, syn. n. of Chrysis
angolensis Radoszkovsky, 1881; Chrysis
chrysochlora Mocsáry, 1889, syn. n. and Chrysis
viridans Radoszkowski, 1891, syn. n. of Chrysis
keriensis Radoszkowski, 1887; Chrysis
angustifrons
var.
ignicollis Trautmann, 1926, syn. n. of Chrysis
eldari (Radoszkowski, 1893); Chrysis
maracandensis
var.
simulatrix Radoszkowski, 1891, syn. n. of Chrysis
maracandensis Radoszkowski, 1877; Chrysis
pulchra Radoszkovsky, 1880, syn. n. of Spinolia
dallatorreana (Mocsáry, 1896); Chrysis
rubricollis du Buysson, 1900, syn. n. of Chrysis
eldari (Radoszkowski, 1893); Chrysis
subcoerulea Radoszkowski, 1891, syn. n. of Chrysis
chlorochrysa Mocsáry, 1889; Chrysis
therates Mocsáry, 1889, syn. n. of Chrysis
principalis Smith, 1874; and Notozus
komarowi Radoszkowski, 1893, syn. n. of Elampus
obesus (Mocsáry, 1890). One species is revaluated: Chrysis
chalcochrysa Mocsáry, 1887. Chrysis
kizilkumiana Rosa is the new name for Chrysis
uljanini Radoszkowski & Mocsáry, 1889 nec Radoszkowski, 1877. Pictures of seventy-seven type specimens are given. 相似文献
11.
12.
13.
Dr. Graham Walker 《Protoplasma》1970,71(1-2):91-109
Summary Four cell types have been identified in the digestive glands from light and electron microscope studies. The possible functions of each cell type are discussed.Thin cells are undifferentiated. Calcium cells contain spherules of calcium salts which have a characteristic ultrastructure. Different protein granules are found apically. Digestive cells are present as two distinct forms. One form is believed to be absorbing food material and digesting it intracellularly, and the other form is a secreting cell. Both forms contain green and yellow granules and histochemistry shows these granules to be distinct. Protein granules also occur apically.Excretory cells are distinguished by having a large central vacuole containing excretory granules. Histochemistry shows these granules, like the yellow granules of digestive cells, to be composed mainly of lipofuscin.It is suggested that digestive cells form excretory cells. 相似文献
14.
The classification of the ovarian stages remains still vague. The ultrastructure of the basal follicle made it possible to solve this problem. From the sixth to the eighth day of the worker bee's adult life, the length of the ovariole hardly exceeds 2 mm. The basal oocytes of stages 1 and 2 are characterized by the presence of many ranges of granules encircled by the dilated cylinders of the granular endoplasmic reticulum. These cylinders decondensate the proteinic granules and the lipidic globules generating multivesicular bodies. The basal oocyte, at the third stage of development, measures 0.35+/-0.05 mm in length. This stage of the previtellogenesis' end is characterized by the appearance, in the ooplasm, of many tubules, whose dilated end constitutes a lysosome. At the beginning of the second week, vitellogenesis starts. Stage 4 is defined by the appearance, in the ooplasm, of the yellow granules in relationship to the tubular formations. At the 14th to 16th days of the adult life, 25+/-7.1% of the worker bees reach the end vitellogenesis, or stage 5. The ovariole, about 7 mm in length, contains 11 follicles. This stage 5 is distinguished by the synthesis from the vitelline membrane, the regression of the size of yellow granules and the accessory cores. The sixth stage or oocyte maturation is reached by 12.5+/-3.5% of the workers aged 18 to 20 days. It is defined by the presence of the chorion, the dissolution of the yellow granules, the disappearance of the accessory nuclei and the total degeneration of the follicular cells. 相似文献
15.
《International Journal of Insect Morphology and Embryology》1991,20(1-2):1-13
Ultrastructure of stemmata (larval eyes), stemmatal nerves, and the optic neuropils of 5th-instar larvae of cotton bollworm, Heliothis armigera (Hübner) (Lepidoptera : Noctuidae), were examined with scanning and transmission electron microscopes. Six stemmata are on each side of the head. Each stemma consists of 7 retinula cells arranged into 2 tiers. Stemmata I and II have 4 distal retinula cells and 3 proximal cells, the other 4 stemmata (III–IV) have 3 distal cells and 4 proximal cells. Stemmata I and IV have a short proximal rhabdom and the rhabdomere of each proximal cell has its microvilli projecting in only one direction. On the other hand, each stemma (in stemmata II–V) has a long proximal rhabdom and the rhabdomere of each proximal cell has microvilli pitched in several different directions relative to the horizontal plane. An axon projects proximally from each retinula cell body. The stemmatal nerve is composed of the 42 retinular axons from all of the 6 stemmata on the same side of the head. Each stemmatal nerve projects to the ipsilateral optic neuropil. Axons from each stemma are in a fasicle (within the stemmatal nerve), which consists of 7 axons, 3–4 of them are thick and terminate synaptically in the proximal neuropil; the others are thinner and terminate in the distal neuropil. Organelles, particularly lysosomes, undergo ultrastructural transformations relative to ambient light levels. The functional significance of abovementioned structures are discussed in light of current knowledge. 相似文献
16.
17.
In this paper, we study a sample of cranial, mandibular and dental remains of two species of the machairodontine felid genus Machairodus from the Early Vallesian (MN 9, around 10 Ma) site of Los Valles de Fuentidueña (Segovia, Spain): the tiger-sized Machairodus aphanistus, and the smaller and more primitive M. alberdiae; a species which is only known from this site. The fossils of these two sympatric populations are compared with the most abundant samples of M. aphanistus from the Late Vallesian (MN 10), younger sites of Batallones-1 and Batallones-3 (Torrejón de Velasco, Madrid, Spain). The results support the specific separation of M. alberdiae from M. aphanistus based on several differences in teeth size and proportions. Besides this, we observed differences among the analysed samples of M. aphanistus, indicating a differentiation between the older and more primitive form from Los Valles de Fuentidueña, and the younger and more derived one from the two Batallones sites. These differences fit well with the morphological evolution of this lineage towards the more derived Turolian Amphimachairodus giganteus. Finally, a relatively structured, patched habitat, combining the presence of open landscapes with shrubby and wooded areas, is inferred to explain the sympatric distribution of these two large machairodontines in Los Valles de Fuentidueña. 相似文献
18.
The Na,K-ATPase is a major ion transport protein found in higher eukaryotic cells. The enzyme is composed of two subunits,
α and β, and tissue-specific isoforms exist for each of these, α1, α2 and α3 and β1, β2 and β3. We have proposed that an additional
α isoform, α4, exists based on genomic and cDNA cloning. The mRNA for this gene is expressed in rats and humans, exclusively
in the testis, however the expression of a corresponding protein has not been demonstrated. In the current study, the putative
α4 isoform has been functionally characterized as a novel isoform of the Na,K-ATPase in both rat testis and in α4 isoform
cDNA transfected 3T3 cells. Using an α4 isoform-specific polyclonal antibody, the protein for this novel isoform is detected
for the first time in both rat testis and in transfected cell lines. Ouabain binding competition assays reveal the presence
of high affinity ouabain receptors in both rat testis and in transfected cell lines that have identical K
D
values. Further studies of this high affinity ouabain receptor show that it also has high affinities for both Na+ and K+. The results from these experiments definitively demonstrate the presence of a novel isoform of the Na,K-ATPase in testis.
Received: 4 December 1998/Revised: 1 February 1999 相似文献
19.
Anna Paula Martins de Carvalho Juliana Ywasaki Lima Carolina Torres Azevedo Silvina Botta Fábio Ferreira de Queiroz Adélia Sepúlveda Campos Lupércio de Araújo Barbosa Leonardo Serafim da Silveira 《PloS one》2015,10(5)
The estuarine dolphin, Sotalia guianensis, is one of the most abundant cetacean species in Brazil. Determination of age and of aspects associated with the development of this species is significant new studies. Counts of growth layer groups in dentin are used to estimate age of these animals, though other ways to evaluate development are also adopted, like the measurement of total length (TL). This study presents a procedure to evaluate the development of the estuarine dolphin based on the ossification pattern of forelimbs. Thirty-seven estuarine dolphins found in the state of Espírito Santo, Brazil, were examined. Age was estimated, TL was measured and ossification of epiphyses was examined by radiography. We analyzed results using the Spearman correlation. Inspection of radiographs allowed evaluation of the significance of the correlation between age and development of the proximal (r = 0.9109) and distal (r = 0.9092) radial epiphyses, and of the distal ulnar epiphyses (r = 0.9055). Radiographic analysis of forelimbs proved to be an appropriate method to evaluate physical maturity, and may be a helpful tool to estimate age of these animals in ecological and population studies. 相似文献
20.
Mizoguchi SM Portela-Castro AL Martins-Santos IC 《Genetics and molecular research : GMR》2007,6(3):650-656
Three populations of the genus Crenicichla, namely Crenicichla iguassuensis, Crenicichla sp 1 and Crenicichla sp 2, from the Igua?u River, were analyzed cytogenetically, and their nucleolus organizer regions, constitutive heterochromatin distribution and chromomycin A3 markings were studied. Karyotype analyses showed a diploid number of 48 chromosomes, made up of 2 metacentric pairs, 2 submetacentric pairs, 7 subtelocentric pairs, and 13 acrocentric pairs for the three Crenicichla species and no sexual chromosome differentiation. Nucleolus organizer regions showed strong interstitial marking on the first chromosome pair, coincident with a constriction presented by Giemsa and positive marking by chromomycin. Although constitutive heterochromatin patterns were also similar, with pericentromeric markings, small differences in the three species could be observed. Crenicichla sp 2 presented some chromosomes with bitelomeric markings absent in Crenicichla iguassuensis and Crenicichla sp 1. 相似文献