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1.
2.
Incubation, handrearing and motherrearing of 5 male Andean Cocks of the Rock (Rupicola peruviana) in Wuppertal Zoo is described, in particular the development of the juvenile plumage to adulthood, and the change of colour of the beak and the iris of the eye. Incubation lasted 26-28 days. The mother-reared nestling fledged after 28 days. The young male Cock of the Rock attained full adult plumage at the age of 18 months, not at 3 years as Del Hoyo et al. (2004) describe from free-living Cocks of the Rock. A report on the supposed world's first breeding of the Purple-throated Fruitcrow (Querula purpurata) is given. The incubation period was 25 days.  相似文献   

3.
The aim of this work was to quantify the intensity of sediment mixing induced by the gallery-diffusor (functional bioturbation group) Hediste diversicolor as a function of density, using particles tracers (luminophores). In order to assess the impact of density on sediment reworking, a 1-D model was used to obtain sediment reworking coefficients such as Db (biodiffusion-like) and r (biotransport). Densities used in this experiment corresponded to population densities observed in the sampling area (Saint-Antoine Canal, Gulf of Fos, France): 144, 288, 577, 1153 indiv/m2. At first, results showed that neither luminophore maximum burying depth nor the more marked tracer accumulation areas were influenced by density. Thus density did not seem to have any influence on size of galleries or complexity of structure. Then, density-dependent relations with Db (biodiffusion-like mixing) and r (biotransport) were highlighted with an observed process intensity rate twice as high at highest worm density. On the other hand, Db and r per capita coefficients were negatively influenced by density. Db and r per capita at highest density were equal to ∼ 20% of individual Db and r obtained at the lowest density. Finally, this study showed the importance of density which appears to be a key parameter in the functioning of the sedimentary ecosystem.  相似文献   

4.
As part of the quantitative investigations into the bioenergetic relationships of the Barents Sea capelin, Mallotus villosus villosus (Müller, 1776), resting metabolic rates were examined in the oviferous and post-spawning fish in order to provide insights to aerobic scaling and the basal energetic costs associated with reproduction. Aerobic scaling of the different categories of sexually mature fish (body weight, W=13-54 g) could be expressed as: QO2=0.106W1.049 (oviferous fish; N=11), QO2=0.411W0.430 (post-spawning females; N=9), and QO2=0.075W1.012 (post-spawning males; N=14), where QO2 is the oxygen consumption (ml O2 h−1) per fish. The weight specific oxygen consumption of oviferous capelin was about 30% higher (∼125 ml O2 kg−1 h−1) compared to those of the post-spawning fish (79-87 ml O2 kg−1 h−1). The results are discussed in context with other empirical studies on the aerobic scaling and metabolic costs involved with the build-up of roe in the fish.  相似文献   

5.
The rhynchonellid brachiopod species Cryptopora lovisati(Dreger, 1911) has been identified in the Middle Miocene sandy deposits of France, and its ontogeny and variability are described. This is the first record of the genus Cryptopora Jeffreys from France, although several species of Cryptopora have been already reported from other regions of Europe. Being known since the Lower Palaeocene, Cryptopora is widely distributed in modern seas, ranging from about 60 m down to over 4000 m, and is represented by six extant and about 12 fossil species. C. lovisati has been interpreted as relatively shallow water species living attached to the sediment by a long pedicle. The affinity between C. lovisati and Recent C. curiosa Cooper is discussed.  相似文献   

6.
It has been extensively documented that exposure of amphibians and teleost fish to exogenous steroid hormones like estrogen, androgen, xenoestrogen or steroid biosynthesis inhibitors can impair their gonadal development or induce sex reversal against genotypic sex. However, the molecular pathways underlying sexual development and the effects of sex steroids or other exogenous hormones in these aquatic vertebrates remain elusive. Recently, a germ plasm-associated piRNA (piwi-interacting RNA) pathway has been shown to be a determinant in the development of animal gonadal germline cells. In the current study, we examined whether this piRNA pathway is involved in the regulation of sex steroid hormones in gonadal development. We firstly established developmental expression patterns of three key piRNA pathway genes (mael, piwi and vasa), during Silurana (Xenopus) tropicalis embryogenesis and early larval development. All three genes exhibit high expression at early developmental stages and have significantly decreased expression thereafter, indicating a very active involvement of piRNA pathway at the beginning of embryogenesis. We further examined gene expression changes of those genes in frog larvae exposed to two sex steroid biosynthesis inhibitors, fadrozole and finasteride, both of which are known to result in male-biased or female-biased phenotypes, respectively. We found that fadrozole and finasteride exposures increased the expression of piRNA pathway genes such as mael and vasa at the larval stage when the expression of piRNA pathway genes is programmed to be very low. Therefore, our results indicate that the piRNA pathway is likely a common pathway by which different sex steroid hormones regulate gonadal sex differentiation.  相似文献   

7.
Developmental plasticity in the morphology of planktotrophic echinoid larvae has been studied primarily in temperate sea urchins from the Northern Hemisphere. These studies have shown that echinoplutei with reduced food ration generally respond by increasing the length of the larval arms, and thus the length of the ciliated band, and delaying formation of the rudiment. Using the endemic New Zealand sea urchin Evechinus chloroticus we tested for the presence of developmental plasticity in larvae fed a high or low algal food ration (6000 or 600 Dunaliella cells/ml), or with no algal food. Our results show that developmental plasticity in larval form is seen in a Southern Hemisphere representative of the Family Echinometridae, but the general pattern of longer arms with low food ration was only seen in the earliest part of development. Larvae in the High food treatment were largest in all dimensions and formed rudiments within 23 days of fertilization. Larvae fed a low algal ration or no algal food stalled at the four-arm echinopluteus stage, and were significantly smaller in size, and differed in shape, when compared in a multivariate analysis to the High food treatment. We suggest that the response of echinoplutei to low levels of particulate food is a species-specific trait, depending in part on the level of dependence of the larvae on exogenous food. Previous studies in Lytechinus variegatus, and the present study with E. chloroticus, suggest that in species where development stalls at the four-arm stage, the pattern of longer larval arms with low food ration will only be seen during the initial early period of larval growth. Additionally our results show that there can be significant variation in larval morphology between replicate jars in the same feeding treatment, suggesting that future research on developmental plasticity should also consider differences in larval morphology between culture containers.  相似文献   

8.
The morphology of the larval stages of three species (Arrenurus mediorotundatus, Arrenurus conicus and Arrenurus cylindratus) belonging to the Megaluracarus subgenus is described. Particular attention is paid to the common characters of the three species in which they differ from the other species belonging to the other subgenera. These are: the shape of the excretory pore plate, the shape of the dorsal plate, the length of coxal plate II medial margin and the C1-CpI, C4-CpIII distances. Other characters differ between the three species also. These are: the shape of the dorsal plate, the shape of coxal plate III, the shape of excretory pore plate and the presence or absence of secondary setae of the IFe3 setae.  相似文献   

9.
The Abildgaardieae tribe within the family Cyperaceae comprises six or seven genera, among which Abildgaardia, Bulbostylis and Fimbristylis pose a challenge regarding their morphological delimitation. Molecular phylogenetic analyses including species of Abildgaardieae are rare, but in most of those studies, Abildgaardia and Fimbristylis appear as more closely related to each other than to the Bulbostylis genus. Duration of the style base has been one of the most widely used characters for delimiting these three genera. The style base is a persistent structure in most species of Bulbostylis and deciduous in Abildgaardia and Fimbristylis. The reasons why the style base may persist or fall off have been scarcely discussed. The assumption that abscission layers are present in the style base of all three genera and the fact that tracheids have been observed in the style base of Bulbostylis suggest that this structure might have histological complexity. In view of this, a complete ontogenetic and anatomical study of the gynoecium has been carried out for all these three genera. It turned out that the style base is histologically simple in Abildgaardia, Bulbostylis and Fimbristylis and shows similar structure and development in all three genera. The fact that the style base has a shorter duration in Abildgaardia and Fimbristylis than in Bulbostylis might be related to the lower number of sclerotised cells that make up such structures in the mature fruit of the former two genera. Abscission of the style and style base may be the result of much simpler reasons than the differentiation of an abscission layer, resulting merely from mechanical shear force effects. Differences among genera have been observed in the shape of the style base and the development of the style. The histological simplicity of the style base is consistent with the homoplastic appearance of this structure in genera that are not closely related (e.g. Rhynchospora). Because of this, while the presence of the thickened style base seems to be a synapomorphy in species of Abildgaardieae, its persistence on or detachment from the fruit might have emerged repeatedly during this clade evolution and might not be a suitable character for genera delimitation.  相似文献   

10.
11.
To examine the life history response and age-specific tolerance to starvation in the rotifer Brachionus plicatilis O.F. Müller, we carried out two series of individual culture experiments. In the first experiment, rotifers were fed until each of the ages of 1-4 days, and were then starved during the rest of their lifetimes. The control group was fed throughout their lifespans. Rotifers stopped active reproduction just after the onset of food deprivation, and showed shorter subsequent survival times when they were starved at older ages. The finding that the larger the number of offspring produced before food deprivation, the shorter the subsequent lifetime under starvation, appeared to reflect a trade-off with the cost of reproduction. In the second experiment, newborns were starved until each of the ages of 1-5 days, and were fed thereafter. The lifespans of the rotifers starved up to the age of 3 days were not statistically different from those that were not starved. Although the starved rotifers began to reproduce once fed again, their lifetime fecundity decreased significantly from that of the non-starved group. Based on these results, it was suggested that the reproductive suppression caused by starvation would cause rotifers to have a longer lifespan to allow for future reproduction.  相似文献   

12.
Ambrosia beetles (Coleoptera: Scolytinae) are associated with strictly entomochoric and mutualistic fungi. We studied the mycobiota associated with Scolytodes unipunctatus, ambrosia beetles that infest Cecropia trees in Central America. Isolates were characterized using morphology and rDNA sequences (ITS region, LSU, and SSU rDNA). Four species are described here: Raffaelea scolytodis sp. nov. (Ophiostomatales), Gondwanamyces scolytodis sp. nov., Custingophora cecropiae sp. nov., and Graphium sp. (Microascales). The genus Custingophora is emended to include Knoxdaviesia anamorphs of Gondwanamyces based on uniformity of DNA sequences and phenotype.  相似文献   

13.
Floral initiation and development of Hedysarum varium, Onobrychis melanotricha and Alhagi persarum was studied using epi-illumination light-microscopy techniques. The studied species belong to the tribe Hedysareae of the inverted repeat loss clade (IRLC clade), which is characterized by missing the large inverted repeat in the chloroplast genome. The main aim of our study was to determine developmental bases for similarities and differences among the three taxa and to verify the position of Alhagi relative to other genera of the IRLC clade. According to our observations, bracteoles are missing in Onobrychis melanotricha, but are present in the other two species. All three species share unidirectional sepal initiation starting with a median abaxial sepal and bidirectional petal initiation. Stamen initiation is unidirectional in all except in the outer stamen whorl of Hedysarum varium, where it is bidirectional. An important ontogenetic feature in O. melanotricha is the existence of five common primordia, which give rise to petal and stamen primordia. Although in H. varium and O. melanotricha common primordia are observed at some stages in floral organ initiations, in Alhagi all organs are initiated separately. Moreover, overlap in time of floral organs initiation occurs in H. varium and O. melanotricha, but not in A. persarum. The carpel initiates concurrently with the petal primordia in all. It might be presumed that Alhagi is primitive in relation to the other studied Hedysareae taxa, due to the presence of bracteoles, the absence of common primordia, and the lack of overlap in time of different organ initiations.  相似文献   

14.
15.
Torrubiella is a genus of arthropod-pathogenic fungi that primarily attacks spiders and scale insects. Based on the morphology of the perithecia, asci, and ascospores, it is classified in Clavicipitaceae s. lat. (Hypocreales), and is considered a close relative of Cordyceps s. 1., which was recently reclassified into three families (Clavicipitaceae s. str., Cordycipitaceae, Ophiocordycipitaceae) and four genera (Cordyceps s. str, Elaphocordyceps, Metacordyceps, and Ophiocordyceps). Torrubiella is distinguished morphologically from Cordyceps s. lat. mainly by the production of superficial perithecia and the absence of a well-developed stipitate stroma. To test and refine evolutionary hypotheses regarding the placement of Torrubiella and its relationship to Cordyceps s. lat., a multi-gene phylogeny was constructed by conducting ML and Bayesian analyses. The monophyly of Torrubiella was rejected by these analyses with species of the genus present in Clavicipitaceae, Cordycipitaceae, and Ophiocordycipitaceae, and often intermixed among species of Cordyceps s. lat. The morphological characters traditionally used to define the genus are, therefore, not phylogenetically informative, with the stipitate stromata being gained and/or lost several times among clavicipitaceous fungi. Two new genera (Conoideocrella, Orbiocrella) are proposed to accommodate two separate lineages of torrubielloid fungi in the Clavicipitaceae s. str. In addition, one species is reclassified in Cordyceps s. str. and three are reclassified in Ophiocordyceps. The phylogenetic importance of anamorphic genera, host affiliation, and stipitate stromata is discussed.  相似文献   

16.
The dynamics of the protozoan parasite Marteilia refringens was studied in Thau lagoon, an important French shellfish site, for 1 year in three potential hosts: the Mediterranean mussel Mytilus galloprovincialis (Mytiliidae), the grooved carpet shell Ruditapes decussatus (Veneriidae) and the copepod Paracartia grani (Acartiidae). Parasite DNA was detected by PCR in R. decussatus. In situ hybridisation showed necrotic cells of M. refringens in the digestive epithelia of some R. decussatus suggesting the non-involvement of this species in the parasite life cycle. In contrast, the detection of M. refringens in mussels using PCR appeared bimodal with two peaks in spring and autumn. Histological observations of PCR-positive mussels revealed the presence of different parasite stages including mature sporangia in spring and autumn. These results suggest that the parasite has two cycles per year in the Thau lagoon and that mussels release parasites into the water column during these two periods. Moreover, PCR detection of the parasite in the copepodid stages of P. grani between June and November supports the hypothesis of the transmission of the parasite from mussels to copepods and conversely. In situ hybridisation performed on copepodites showed labeling in some sections. Unusual M. refringens cells were observed in the digestive tract and the gonad from the third copepodid stage, suggesting that the parasite could infect a copepod by ingestion and be released through the gonad. This hypothesis is supported by the PCR detection of parasite DNA in copepod eggs from PCR-positive females, which suggests that eggs could contribute to the parasite spreading in the water and could allow overwintering of M. refringens. Finally, in order to understand the interactions between mussels and copepods, mussel retention efficiency (number of copepods retained by a mussel) was measured for all P. grani developmental stages. Results showed that all copepod stages could contribute to the transmission of the parasite, especially eggs and nauplii which were retained by up to 90%.  相似文献   

17.
The Heliohebe group of Veronica (sect. Hebe) consists of five species occurring in the South Island of New Zealand. These species and a hybrid were analysed for their flavonoids. Five flavone glycosides were isolated and identified by NMR spectroscopy and three additional glycosides were detected by LC–UV–MS. Luteolin 7-O-, 3′-O- and 4′-O-glucosides and apigenin 7-O-glucoside were present in all six taxa investigated, 6-hydroxyluteolin glycosides were found in five and a luteolin caffeoylglycoside in four taxa, while a hypolaetin 7-O-glycoside was detected only in Veronica pentasepala. The 3′-O- and 4′-O-glucosides of luteolin are also common in other species of Veronica sect. Hebe (restricted to the Southern Hemisphere), but are rare in Northern Hemisphere species of Veronica and thus act as good chemotaxonomic markers for the section. The relatively simple flavonoid profiles found in the Heliohebe group are plesiomorphic and consistent with the group's status as sister to the Hebe clade. Based on the detected flavonoids, two groups could be distinguished within the Heliohebe clade: (1) Veronica hulkeana, Veronica lavaudiana and Veronica raoulii, characterised by luteolin caffeoylglycoside, and (2) V. pentasepala and Veronica scrupea, where this compound is replaced by a 6-hydroxyluteolin dihexoside.  相似文献   

18.
Parmeliaceae is the largest family of lichen-forming fungi. In spite of its importance for fungal diversity, its relationships with other families in Lecanorales remain poorly known. To better understand the evolutionary history of the diversification of lineages and species richness in Parmeliaceae it is important to know the phylogenetic relationships of the closest relatives of the family. A recent study based on two molecular loci suggested that either Protoparmelia s. str. or a group consisting of Gypsoplaca and Protoparmelia s. str. were the possible sister-group candidates of Parmeliaceae, but that study could not distinguish between these two alternatives. Here, we used a four-locus phylogeny (nuLSU, ITS, RPB1, MCM7) to reveal relationships of Parmeliaceae with other potential relatives in Lecanorales. Maximum likelihood and Bayesian analyses showed that Protoparmelia is polyphyletic, with Protoparmelia s. str. (including Protoparmelia badia and Protoparmelia picea) being most closely related to Parmeliaceae s. str., while the Protoparmelia atriseda-group formed the sister-group to Miriquidica. Gypsoplaca formed the sister-group to the Parmeliaceae s. str. + Protoparmelia s. str. clade. Monophyly of Protoparmelia as currently circumscribed, and Gypsoplaca as sister-group to Parmeliaceae s. str. were both significantly rejected by alternative hypothesis testing.  相似文献   

19.
A polydnavirus, Cotesia plutellae bracovirus (CpBV), possesses a segmented and dispersed genome that is located on chromosome(s) of its symbiotic endoparasitic wasp, C. plutellae. When the host wasp parasitizes larvae of the diamondback moth, Plutella xylostella, at least 27 viral genome segments are delivered to the parasitized host along with the wasp egg. The parasitized P. xylostella exhibits significant immunosuppression and a prolonged larval development. Parasitized larvae take about 2 days longer than nonparasitized larvae to develop until the wandering stage of the final larval instar, and die after egress of the full grown wasp larvae. Developmental analysis using juvenile hormone and ecdysteroid analogs suggests that altering endocrine signals could induce the retardation of larval developmental rate in P. xylostella. In this study we used a transient expression technique to micro-inject individual CpBV genome segments, and tested their ability to induce delayed larval development of P. xylostella. We demonstrated that a CpBV segment was able to express its own encoded genes when it was injected into nonparasitized larvae, in which the expression patterns of the segment genes were similar to those in the larvae parasitized by C. plutellae. Twenty three CpBV genome segments were individually cloned and injected into the second instar larvae of P. xylostella and their effects assessed by measuring the time taken for host development to the cocooning stage. Three CpBV genome segments markedly interfered with the host larval development. When the putative genes of these segments were analyzed, it was found that they did not share any common genes. Among these segments able to delay host development, segment S27 was predicted to encode seven protein tyrosine phosphatases (CpBV-PTPs), some of which were mutated by insertional inactivation with transposons, while other encoded gene expressions were unaffected. The mutant segments were unable to induce prolonged larval development of P. xylostella. These results suggest that CpBV can induce prolonged larval development of P. xylostella, and that at least some CpBV-PTPs may contribute to the parasitic role probably by altering titers of developmental hormones.  相似文献   

20.
Hyaloscyphaceae is the largest family in Helotiales, Leotiomycetes. It is mainly characterized by minute apothecia with well-differentiated hairs, but its taxonomic delimitation and infrafamilial classification remain ambiguous. This study performed molecular phylogenetic analyses using multiple genes including the ITS-5.8S rDNA, the D1–D2 region of large subunit of rDNA, RNA polymerase II subunit 2, and the mitochondrial small subunit. The primary objective was to evaluate the phylogenetic utility of morphological characters traditionally used in the taxonomy of Hyaloscyphaceae through reassessment of the monophyly of this family and its genera. The phylogenetic analyses inferred Hyaloscyphaceae as being a heterogeneous assemblage of a diverse group of fungi and not supported as monophyletic. Among the three tribes of Hyaloscyphaceae only Lachneae formed a monophyletic lineage. The presence of hairs is rejected as a synapomorphy, since morphologically diversified hairs have originated independently during the evolution of Helotiales. The true- and false-subiculum in Arachnopezizeae are hypothesized to have evolved through different evolutionary processes; the true-subiculum is likely the product of a single evolutionary origin, while the false-subiculum is hypothesized to have originated multiple times. Since Hyaloscyphaceae sensu lato was not resolved as monophyletic, Hyaloscyphaceae sensu stricto is redefined and only applied to the genus Hyaloscypha.  相似文献   

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