Italian Journal of Zoology最新文献

{"title":"The cytological changes of sperm and oocyte nuclei during fertilization in Phascolosoma esculenta (Sipuncula: Phascolosomatidea)","authors":"L. Long, Z. Sheng, S. Xu, W. Wang, J. Zhu","doi":"10.1080/11250003.2015.1045045","DOIUrl":"https://doi.org/10.1080/11250003.2015.1045045","url":null,"abstract":"Abstract In this study, we investigated fertilization cytology in Phascolosoma esculenta. The sperm binds to the oocyte envelope in a random position at the point of initial contact. An acrosomal reaction then occurs and the acrosomal filament penetrates the oocyte envelope. The apex of the acrosomal filament contacts with the plasma membrane of the oocyte at the point where the fertilization cone is formed. The fertilization cone then retracts, towing the acrosomal filament back and drawing the sperm into the oocyte. Subsequently, the pores on the oocyte envelope are blocked and filled with fibrin and colloid. After the oocyte is activated by sperm, the first and second meiosis processes start sequentially, followed by the release of the first and second polar bodies. After the second polar body is extruded, the haploid female nucleus rapidly reorganizes to form a female pronucleus. In comparison, the sperm nucleus begins to decondense and dilate after the first polar body is released. The male pronucleus is not formed until the end of the second meiosis. The male and female pronuclei migrate to the centre of the oosperm and are incorporated into the zygote nucleus and then the first cleavage occurs. A two cell embryo is then formed by plasma membrane invagination. The cytological changes of sperm and oocyte nuclei during sperm entry into the oocyte and the fertilization process in P. esculenta are characterized by: (1) the mature oocyte with fertilization ability being in the metaphase of the first meiosis; (2) sperm is drawn into the oocyte by the acrosomal filament and fertilization cone; (3) some abnormal phenomena such as polyspermy, multiple pronuclei and multipolar spindle; and (4) the male pronucleus is formed earlier than the female pronucleus, at which point they will fuse to form a zygote nucleus.","PeriodicalId":14615,"journal":{"name":"Italian Journal of Zoology","volume":"3 1","pages":"327 - 337"},"PeriodicalIF":0.0,"publicationDate":"2015-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80871575","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Field estimates of detectability and site occupancy show that northern Italy forest molluscs are spatially rare and poorly detectable","authors":"P. Albano, G. Strazzari, P. D’Occhio, F. Succetti","doi":"10.1080/11250003.2015.1040084","DOIUrl":"https://doi.org/10.1080/11250003.2015.1040084","url":null,"abstract":"Abstract Estimations of site occupancy of species and their vital rates, and of species richness of a community, are biased if detection probability is not taken into account. Models that allow the joint estimation of occupancy and detectability were used in a land mollusc survey in six forest habitats in northern Italy, allowing estimations for 55 species of land snails. Most species were poorly detectable (p ≤ 0.3). Detectability varied among habitats and collecting techniques. Taking into account detectability, occupancy estimations may be from 15 to 85% larger than the naïve occupancy values computed by dividing the number of stations at which the species was detected by the total number of stations (0.13–0.42 in absolute terms), significantly altering our understanding of species rarity. In several habitats the share of spatially rare species was remarkably high, above 30%, with peaks above 60%; at the regional scale 62.7% for visual sampling and 46.7% for leaf litter and soil sampling. The sampling effort to monitor occupancy for the numerous uncommon to rare species is well above what would be satisfactory in terms of saturation of species inventory. Visual search gave higher estimates of detectability for species above 1 cm in size, while leaf litter and soil sorting gave higher estimates for species below 1 cm. Consideration of fresh empty shells along with living individuals allowed us to improve the estimates, but when interpreting results the bias induced by taphonomic processes has to be considered. When detection probabilities are unknown, an estimate of their order of magnitude may be obtained by relative abundances, while shell size does not correlate significantly with detectability.","PeriodicalId":14615,"journal":{"name":"Italian Journal of Zoology","volume":"7 1","pages":"592 - 608"},"PeriodicalIF":0.0,"publicationDate":"2015-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78112265","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Morphological and histochemical studies of Bidder’s organ in Rhinella schneideri (Amphibia: Anura) males","authors":"J. Silberschmidt Freitas, L. Franco‐Belussi, C. de Oliveira","doi":"10.1080/11250003.2015.1042934","DOIUrl":"https://doi.org/10.1080/11250003.2015.1042934","url":null,"abstract":"Abstract Bufonids have an organ that produces female germ cells in both sexes, known as the Bidder’s organ (BO). In males, BO is located in the anterior pole of the testis and it has been compared to a rudimentary ovary. It has been demonstrated that in some species the bidderian follicles can accumulate vitellogenin in males, while in other species, the development of follicles is inhibited by the differentiation of the corresponding gonad. This study describes the anatomical, histochemical and ultrastructural aspects of the BO in males of the neotropical frog Rhinella schneideri during the breeding season. A topographic model has also been built using three-dimensional (3D) reconstruction. BO has an irregular shape with lobes varying in size and number. There is no physical barrier between the BO and male gonads and, for this reason, female cells are in intimate association with seminiferous locules. Histologically, two distinct regions are observed in the BO: the cortex, and medulla. In the cortex, bidderian oocytes are surrounded by follicle cells forming bidderian follicles, which are in pre-vitellogenic stage. The ooplasm of bidderian oocytes is rich in cytoplasmic organelles. Microvilosities are formed in the oolemma, where the follicular cells are juxtaposed with oocytes, and amorphous extracellular material is deposited. Lipofuscin and myelin bodies occur in the medulla as a result of the cellular degradation. Pigmented cells were also detected in the medullar region. The oogonias observed in the BO periphery, and the significant amount of degenerating oocytes in the cortex, showed the renewal capacity of BO cells in R. schneideri males. The BO anatomical pattern in R. schneideri is similar to that observed for most species of bufonids. This work describes for the first time specific aspects related to the morphological description with emphasis on architecture, morphometry and histochemistry.","PeriodicalId":14615,"journal":{"name":"Italian Journal of Zoology","volume":"18 1","pages":"479 - 488"},"PeriodicalIF":0.0,"publicationDate":"2015-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84835691","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Morphology of the stridulatory organs of Iberian myrmicine ants (Hymenoptera: Formicidae)","authors":"S. Castro, M. Álvarez, M. Munguira","doi":"10.1080/11250003.2015.1038323","DOIUrl":"https://doi.org/10.1080/11250003.2015.1038323","url":null,"abstract":"Abstract The importance of chemical communication in ants has been widely reported, but acoustic communication also has a significant role in those subfamilies that show this behaviour. In this study, we expand the knowledge about stridulatory organs of the subfamily Myrmicinae (Hymenoptera: Formicidae) with the first description of the stridulatory organs of five species (Aphaenogaster striativentris, Goniomma blanci, G. hispanicum, Oxyopomyrmex salulcyi and Pheidole pallidula). Subsequently, we made a morphometric study of 16 species to make comparisons of their stridulatory organs. Scanning electron microscope (SEM) photographs were taken for the morphological study, and the head and dimensions of the pars stridens, together with measurements of the striae, were used for the morphometric analysis. The five myrmicines studied show typical stridulatory organs for Formicidae. We also add two genera (Goniomma and Oxyopomyrmex) to the list of genera that are known to have stridulatory organs. The morphometric study shows a positive correlation between the body size and the size of the pars stridens and between the length and width of the pars stridens. However, a relation between the size of the stridulatory organs and the size of the striae of the pars stridens was not detected. Stridulatory organs have been shown to have significant interspecific differences in size.","PeriodicalId":14615,"journal":{"name":"Italian Journal of Zoology","volume":"53 1","pages":"387 - 397"},"PeriodicalIF":0.0,"publicationDate":"2015-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78299096","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"New records and underwater observation of the rare fish Scorpaenodes arenai (Osteichthyes: Scorpaenidae) from the central and western Mediterranean Sea","authors":"P. Battaglia, S. Canese, G. Ammendolia, T. Romeo, R. Sandulli, L. Tunesi, F. Andaloro","doi":"10.1080/11250003.2015.1028485","DOIUrl":"https://doi.org/10.1080/11250003.2015.1028485","url":null,"abstract":"Abstract New records of the rare Messina rockfish Scorpaenodes arenai (Osteichthyes: Scorpaenidae) stranded on the Sicilian coast of the Strait of Messina (central Mediterranean Sea) are reported. Morphometric and meristic characters are given together with information on age data. The first underwater observations by remotely operated vehicle (ROV) in different Mediterranean areas contribute to improve current knowledge on distribution, behavior and habitat preference of this species.","PeriodicalId":14615,"journal":{"name":"Italian Journal of Zoology","volume":"15 1","pages":"454 - 458"},"PeriodicalIF":0.0,"publicationDate":"2015-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73917650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First report of live deep-water cnidarian assemblages from the Malta Escarpment","authors":"L. Angeletti, A. Mecho, C. Doya, Aaron Micallef, V. Huvenne, A. Georgiopoulou, M. Taviani","doi":"10.1080/11250003.2015.1026416","DOIUrl":"https://doi.org/10.1080/11250003.2015.1026416","url":null,"abstract":"Abstract A recent geo-marine survey of the Malta Escarpment revealed for the first time the existence of live cnidarian assemblages at about 300 m depth. These associations have been observed by means of a remotely operated vehicle (ROV) during surveys carried out on the upper part of the Malta Escarpment. The assemblages established on hard bedrock were chiefly composed of the antipatharian Leiopathes glaberrima. The Malta Escarpment is known to have been successfully colonised by deep-water scleractinian assemblages until the last glacial age. However, no living specimens had been observed, and only specimens of dead but relatively fresh Dendrophyllia cornigera had been reported. This area of the Mediterranean Sea, which connects the deep Ionian basin to the western Mediterranean, is largely unknown and in clear need of thorough exploration.","PeriodicalId":14615,"journal":{"name":"Italian Journal of Zoology","volume":"22 1","pages":"291 - 297"},"PeriodicalIF":0.0,"publicationDate":"2015-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89630182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"We need monographs, and revisions","authors":"F. Boero","doi":"10.1080/11250003.2015.1041718","DOIUrl":"https://doi.org/10.1080/11250003.2015.1041718","url":null,"abstract":"The production of monographs has kept zoologists busy for a very long time. Monographs often cover the material collected during expeditions and are mostly produced as books. Journals have not much to do with monographs, but they often contribute to the publication of the intermediate work that is conducive to their production. Revisions of higher taxa, often containing the description of new species, are the main type of contribution leading to a monograph. Monographs must cover a well-settled knowledge, even though it is inevitable that they are rapidly destined to become obsolete for several reasons. The exploration of biodiversity is not finished yet, and there are more species to be discovered than those that have already received a name. The disentangling of phylogenies often leads to merging taxa, or to splitting them, with inevitable changes in nomenclature. Furthermore, species move. If a monograph covers a given region, it is often the case that, in the course of decades, new species arrive from elsewhere, and well-known species become rare or even locally extinct. Like all things in biology, faunas are dynamic. The preparation of a monograph is the product of decades of work. Electronic publication is a perfect tool for monographs, since it allows for updates and corrections as soon as new knowledge becomes available. The Fauna of Italy, so far, is covered by 44 monographs that started to be produced in the 1950s. They treat a small part of the fauna and, obviously, the old ones need to be thoroughly revised. Several monographs are waiting to be published, but it is increasingly rare to find authors with sufficient expertise to produce such pieces of work. Due to the current evaluation measures of scientific production, monographs receive limited reward: they are just one title in own publication score, and the lack of impact factor is considered as an index of low quality. It does not matter if the number of pages is in the hundreds and citations are made for a very long time, with an almost infinite shelf life for these products. This kind of science is in a paradoxical situation. The importance of biodiversity is universally acknowledged, and monographs are just the catalogue of the natural capital that sustains us, allowing for the functioning of ecosystems. With these premises, it should be obvious that the exploration of biodiversity and its inventorying is the most urgent priority for mankind. Our impact on biodiversity is affecting the goods and services that benefit us and that are vital for our well being. The knowledge of the natural capital is urgent because we are eroding it now, and the effects of this erosion are overwhelmingly evident. This should lead to huge investments in the production of monographs and to give a high value to the expertise leading to their production. Instead, the expertise is vanishing, and there is no money for this kind of research. The series of monographs covering the Fauna of Italy, due to th","PeriodicalId":14615,"journal":{"name":"Italian Journal of Zoology","volume":"2 1","pages":"149 - 150"},"PeriodicalIF":0.0,"publicationDate":"2015-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73608066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Distribution of brown trout (Salmo trutta Linnaeus, 1758) (Teleostei: Salmonidae) in its southwesternmost European limit: possible causes","authors":"J. E. Larios-López, J. M. Tierno de Figueroa, C. Alonso-González, B. Nebot Sanz","doi":"10.1080/11250003.2015.1018351","DOIUrl":"https://doi.org/10.1080/11250003.2015.1018351","url":null,"abstract":"Abstract Andalusian brown trout populations represent the southwestern limit of this species in Europe, show a high genetic diversity, are subjected to extreme habitat conditions and environmental alterations, and are very sensitive to extinction. However, there is a lack of scientific studies on them. A necessary first step to preserve them is to describe their spatial distribution. We detected the species in eastern Andalusia along almost 710 km of rivers, finding 38 populations inhabiting streams and reservoirs in the upper reaches of three basins (Guadalquivir, Segura and South) in an altitude range between 200 and 2200 m above sea level. Populations are constrained by natural causes in their upper limits, and by anthropogenic causes in their lower limits (mainly related to water management). Currently, the populations are very isolated in protected areas (62% of their distribution) or downstream of those areas (32%), and a range displacement towards higher altitudes compared with their distribution in the nineteenth century is observed.","PeriodicalId":14615,"journal":{"name":"Italian Journal of Zoology","volume":"1 1","pages":"404 - 415"},"PeriodicalIF":0.0,"publicationDate":"2015-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83558200","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ontogenetic change in the body length–mass relationship concomitant to the onset of vitellogenesis in female blackmouth catshark Galeus melastomus (Chondrichthyes: Scyliorhinidae)","authors":"G. Bello, R. Zupa, A. Corriero","doi":"10.1080/11250003.2015.1027308","DOIUrl":"https://doi.org/10.1080/11250003.2015.1027308","url":null,"abstract":"Abstract The examination of the total length (L) vs. body mass (W) relationship in the blackmouth catshark from the southern Adriatic Sea showed the occurrence of two development phases or growth stanzas in females. The passage from the first stanza (L range: 22.8–37.4 cm) to the following one (L range: 39.7–51.4 cm) was marked by an inflection in the power equation correlating body mass to total length, occurring at about 38.6 cm of length (change point). After the change point, growth became positively allometric. This catshark is a lecitotrophic oviparous continuous spawner, and follicles in different stages of development are simultaneously present in the ovary. The histological analysis of the ovary showed that the smallest vitellogenic follicles were about 2 mm in diameter; the diameter of the largest observed oocyte was 18 mm. The change point occurred slightly before the onset of vitellogenesis (smallest vitellogenic female L = 41.0 cm) and appeared to be related to the activation of the reproductive axis.","PeriodicalId":14615,"journal":{"name":"Italian Journal of Zoology","volume":"44 1","pages":"358 - 365"},"PeriodicalIF":0.0,"publicationDate":"2015-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77932549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Surface architecture of the olfactory epithelium of two Chinese cave loaches (Cypriniformes: Nemacheilidae: Oreonectes)","authors":"B. Waryani, Y. Zhao, C. Zhang, A. R. Abbasi, S. Ferrando, R. Dai, A. N. Soomro, W. A. Baloch, Ghulam Abbas","doi":"10.1080/11250003.2015.1018851","DOIUrl":"https://doi.org/10.1080/11250003.2015.1018851","url":null,"abstract":"Abstract The surface of the olfactory epithelium of two species of cave loaches in China, Oreonectes polystigmus and O. guananensis, was studied by scanning electron microscopy (SEM). The structure of the olfactory organ of the two species is quite different from each other; as well, the distribution patterns of cell types in the olfactory epithelium of the studied species showed interesting features. A needle-like spine is visible on the lamellae of the olfactory organ of O. polystigmus, which is a unique character in this species. Ciliated non-sensory cells and microvillus sensory cells showed a different distribution in the two species, being more numerous in O. polystigmus. The non-sensory elements in O. guananensis were ciliated non-sensory cells, with microridges and chloride cells. The presence of chloride cells in the olfactory epithelium of O. guananensis may be of special interest in this species; otherwise, possible differences and physiological changes of the concerned species should be taken into account in order to explain such variability in cell types.","PeriodicalId":14615,"journal":{"name":"Italian Journal of Zoology","volume":"27 1","pages":"179 - 185"},"PeriodicalIF":0.0,"publicationDate":"2015-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84827264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}