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1.
Fefilova  E. B. 《Biology Bulletin》2021,48(8):1231-1235
Biology Bulletin - The morphological characters and biology of the copepod genus Nordodiaptomus Wilson from temporary waterbodies lying in the northern part of the middle taiga belt of the Komi...  相似文献   

2.
An identification guide is presented for species of calanoid copepod family Diaptomidae from “de la Plata” River Basin (Argentina, Brazil, Bolivia, Paraguay and Uruguay). It was based on material collected during the summer and winter of 2010 from 43 sites across the eastern part and the lower stretches of this basin, the second largest in South America and the fourth in the world. The guide contains identification keys and species diagnoses for males and females, richly supported by scanning electronic micrographs and/or line drawings of 19 species. It also includes some general remarks on the taxonomy and phylogenetic relationships of these species. The key was adjusted to be useful for these species only, with separate keys for each sex, and is the first for females of South America. One species classified herein as incertae sedis was not included in the analysis. At least ten other species have previously been recorded in the basin but were not present in our samples. This is the first attempt to compile comprehensive taxonomic information on this group of copepods in this region, and it is expected to become a useful tool for biologists and young taxonomists interested in the crustacean biota of the Neotropical region.  相似文献   

3.
Leising  Andrew W.  Franks  Peter J.S. 《Hydrobiologia》2002,480(1-3):193-207
The swimming behavior of Acartia clausi within small aquaria containing phytoplankton was videotaped, along with unfed controls. From these videos, aspects such as swimming speed, distance traveled, and 2D (horizontal, X, and vertical, Z) headings were then measured from over 75000 X Z positional data in order to quantify their swimming functional response. There was generally no significant difference in swimming behavior between different food levels, although there was a large difference between feeding and unfed controls. Because feeding bouts moved the copepods a short distance at a slow speed, net vertical displacement decreased as feeding-bout frequency increased. Non-feeding individuals showed longer periods of sinking, interspersed with longer-distance, high-speed jumps, which displaced them farther distances than filter-feeding copepods over the same time interval. For both fed and unfed control copepods, a 1D unbiased random walk was adequate to describe their displacement over these very short time periods (10 s). This behavior is consistent with an area-restricted search foraging strategy. The net vertical displacements predicted by combining the experimental data with a 1D random walk model suggest that A. clausi would be retained within even small 10 cm phytoplankton patches long enough to fill their gut. However, copepods outside of phytoplankton patches must rely on other means to find patches of food greater than 50 cm apart. Potentially, knowledge of a copepod's swimming functional response could enable predictions about the typical spatial and temporal patchiness of its food in situ.  相似文献   

4.
The effect of food concentration on gut clearance time of a pelagic copepod, Pseudocalanus minutus Krøyer, was investigated. Gut clearance time was estimated from ingestion rate and gut content pigment of copepods which were continuously fed during experiments. The time estimated by this method was longer than that estimated by evacuation of gut content pigment in filtered sea water by a factor of 1.3 to 2.6. Gut clearance time showed fluctuation with food concentration over 1.6 to 3.3. h, whereas food category had little effect on the time.  相似文献   

5.
Revision of the Asiatic representatives of the genus Tropodiaptomus. Of the 20 names hitherto given for species or varieties, one is a nomen nudum, 9 forms are characterized insufficiently and, hence, their taxonomical position is still uncertain, 10 species are redescribed and illustrated, and 2 taxa have proved to be new to science.
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6.
7.
During monthly sampling from Lake Alada (Bolu, Turkey) between April 2003 and June 2004, nine ostracod taxa (Candona candida, Cypridopsis vidua, Darwinula stevensoni, Eucypris virens, Eucypris sp., Heterocypris sp., Limnocythere inopinata, Physocypria kraepelini, and Tonnacypris lutaria) were recorded from seven stations. Physocypria kraepelini was commonly found in the lake while the others were recorded in particular months. UPGMA analyses clustered three groups based on their occurrence. Accordingly, the occurrence of species (C. candida, E. virens, and T. lutaria) was positive and significantly related to each other. Two species, P. kraepelini and D. stevensoni, showed a significant positive relationship with electrical conductivity. A significant negative correlation was found between the occurrence of P. kraepelini and dissolved oxygen, while there was a significant positive correlation between the occurrence of P. kraepelini and turbidity. About 76% of the relationship between species and environmental factors was explained by the first two axes of canonical correspondence analyses (CCA). Temperature and dissolved oxygen were the two most important influences on the species assemblages. All species showed different but high optima and tolerance ranges, corresponding with their cosmopolitan characteristics. These responses may be related to unstable ecological characteristics of Lake Alada, which is often subjected to human activity.  相似文献   

8.
The mammalian fauna from Gülpinar (Canakkale, Turkey), dated Turolian, comprises threeHipparion taxa:H. cf.matthewi, H. sp. medium-sized, andH. sp. large. Two metatarsals may represent a fourth taxon or may derive from a different locality. The hipparion material is described here.  相似文献   

9.
A study on ecological records of planktonic copepods from The Ventosa Bay, Oaxaca, Mexico is presented. Five species were identified: Labidocera acuta, L. lubbockii, Pontella agassizi, P. tenuiremis and Pontellina plumata. The most abundant species was L. acuta and their copepodite stages conforming the 95.7% of Pontellids, followed by L. lubbockii 4.09%; other species were less than one percent. The reproductive success of L. acuta is probably favored by its resistance to the changes in temperature and salinity, because of it is an eurytherme and euryhaline organism. Total density of this family was between 18 and 472 copepods/100 m3 in 1987 and 1988. Nevertheless in 1992 and 1993 the density was between 490 to 123,030 copepods/100 m3. This copepod density increment could be related local phenomenon (upwelling) at the beginning and end of the year.  相似文献   

10.
Although the area of Lake Yeniça?a is a potential candidate for RAMSAR convention, several anthropogenic factors compromise its biological diversity. This is mostly due to nutrient-rich water released from both point and nonpoint sources. Thirteen ostracod taxa (Candona neglecta, C. candida, Ilyocypris bradyi, Darwinula stevensoni, Cypridopsis vidua, Physocypria kraepelini, Cypria ophtalmica, Prionocypris zenkeri, Eucypris virens, Herpetocypris reptans, Pseudocandona compressa, Fabaeformiscandona fabaeformis Potamocypris cf. fulva) were found during this study. Potamocypris cf. fulva is a new record for the Turkish freshwater ostracod fauna. The first nine of these species have broad geographic ranges, implying high tolerance levels to different environmental variables. Based on the estimated species optima and tolerance levels, two species exhibited higher effective number of occurrences (C. neglecta, and D. stevensoni, respectively) than the other species. Three species (C. neglecta, D. stevensoni, I. bradyi) did not show significant correlation with any environmental variable we used. Both Canonical correspondence (CCA) and Pearson correlation analyses showed that temperature was the most effective predictor of species occurrence, followed by electrical conductivity and redox potential. In contrast, pH and dissolved oxygen of water were the least effective predictors. Approximately 71% of the correlation between community composition and environmental variables was explained by the first axis of the CCA diagram, which had a relatively low (7.7%) cumulative variance of species. The lower (560 μg/l) and the upper (2030 μg/l) levels of ammonia (NH3) exceeded the limits during winter season. The concentrations of total coliform and Escherichia coli bacteria were measured up to 10 × 107 cfu/ml and 10 × 103 cfu/ml, respectively. Results of physicochemical measurements, microbiological counts, and species data indicate that water quality of Lake Yeniça?a has been rapidly deteriorated by anthropogenic factors that are the main threat for not only the lake’s aquatic diversity but also human health around the lake.  相似文献   

11.
12.
Seventeen ostracod species were recorded from Lake Gölköy (Bolu, Turkey) between January 2000 and December 2001. Limnocythere inopinata is a new record for the Bolu region. Canonical Correspondence Analysis (CCA) explained 73% of the correlation between species and environmental variables, suggesting that the occurrence of many species is temporally variable, and is related to seasonal changes in physico-chemical conditions. The four most frequently occurring cosmopolitan ostracod species (Candona neglecta, Darwinula stevensoni, Physocypria kraepelini, and Cypridopsis vidua) accounted for more than 70% of the species recorded. Water temperature, dissolved oxygen (DO), and redox potential were the most affective variables on the species occurrence. Two species (C. vidua, I. bradyi) were positively correlated to redox potential, while such a correlation was negative for P. kraepelini. The most frequently occurring species C. neglecta was most closely related to the changes in redox potential, whereas C. vidua and D. stevensoni showed a positive correlation to water temperature. Negative strong correlation (p<0.01) was found between pH and I. bradyi, but correlation was positive and weak for C. vidua. Some species (e.g. L. inopinata) showed no clear relationship with any of those environmental variables. UPGMA clustering of species based on their occurrence in different ecological conditions revealed three main species assemblages. Analysis of species phenology using the ‘Ostracod Watch Model’ showed that temporal patterns of occurrence could be similar among species with similar ecological preferences. The current status of the lake is discussed based on the present study.  相似文献   

13.
The gonadal structure and cycle of the Leguminaia whaetleyi is described for the first time indicating that 5% of this species is simultaneous hermaphrodite. A total of 420 individuals were collected in monthly samples from October 2008 to September 2009 in G?lba?? Lake, Turkey. Calculation of the condition index and histological examination of the gonads showed that gametogenesis began in January. Spawning occurred between May and August with one maximum peak in July. Annual maximum oocytes size peaked in July. The population consisted of simultaneous hermaphrodite individuals. Sex ratio of L. whaetleyi was significantly different from the expected 1:1 ratio (P< 0.05), and also female biased sex ratio was recorded. In hermaphrodite specimens, male and female follicles were mixed in the visceral mass but can be clearly distinguished by light microscopy study. L. whaetleyi appears to be a dioecious species in which 25 specimens were simultaneous hermaphrodite and under certain environmental conditions may be capable of self-fertilization. This suggests that detailed studies on sex ratio of L. whaetleyi may be helpful in understanding unionid phylogeny.  相似文献   

14.
15.
Stoch  Fabio 《Hydrobiologia》2001,(1):525-531
The genus Diacyclops Kiefer, 1927 emend. Morton (1985) includes more than 100 species, widely distributed in all kinds of freshwater environments, and is the richest genus in the family Cyclopidae. Traditionally, Diacyclops species were defined according to differences in a few morphological characters; some characters (number of antennulary segments, segmentation pattern of swimming legs) are useful only in the separation of species groups, others (length of caudal rami and caudal setae) are highly variable even within the same population. During the study of the D. languidoides-group, minute morphological characters were used to differentiate between species (spinulation pattern and setation of antennary basis, setation and aesthetasc shape of male antennule, setation of mandibulary palp and maxilliped, shape of leg 4 basis) which allow to identify several valid species up to now concealed under the name `Diacyclops languidoides' (Lilljeborg, 1901). The coexistence of up to six congeneric species in the same sampling area: (a) supports the validity of the proposed taxonomic characters, (b) demonstrates that species richness may be highly underestimated in freshwater cyclopoid assemblages in absence of good taxonomic practice; and (c) requires an ecological explanation of species coexistence. The role of morphologically based taxonomy in order to solve general problems of distributional ecology and theoretical biology is explored.  相似文献   

16.
The climatic preferences of Pelias barani, a rare Pontic endemic viper, are analysed and a new locality record is reported. According to species distribution modeling, with the average test AUC was was 0.904 ± 0.068, bioclimatic variables such as Precipitation of driest month(45.5%), Temperature seasonality(18.9%), Precipitation seasonality(17.9%) and Maximum temperature of warmest period(14.7%) appear to have the most useful information on geographic distribution of Pelias barani. Distribution models of Pelias barani under current climatic conditions showed better adaptation to the northwest and northeast part of Turkey.  相似文献   

17.
The Ni?angahtepe Formation (Teke Dere unit) in the Lycian Nappes, and reworked pebbles and blocks from the Late Triassic Gevne Formation in the Alada? unit (both in Southern Turkey), present a well-developed Kubergandian microfauna and microflora found for the first time in this area. The following cyanobacterial and algal taxa are newly established: Clinortonella nov. gen., Ramovsia lyciana nov. sp., and Kantia? guevenci nov. sp.; some Cancellina and Armenina are revised. These Kubergandian faunas and floras present strong palaeobiogeographical affinities with the Eurasian southern margin (northern Palaeotethyan border). The Teke Dere unit represents an accretionary prism/fore-arc sequence containing different parts of the Palaeotethyan succession. The Late Triassic Gevne Formation marks the Eo-Cimmerian unconformity related to the closure of the Palaeotethys between the Taurus and Anatolian terranes.  相似文献   

18.
The marbled spinefoot, Siganus rivulatus (Forsskål&Niebuhr, 1775) was recorded for the first time in Izmit Bay, Sea of Marmara. One specimen was caught on 30 September 2019 by a small scale fisherman at depth of 25 m. The fish measured 151 mm in total length and weighted of 43.45 g. S. rivulatus is one of the Lessepsian immigrants who entered the Mediterranean more than half a century ago, and has now also easily adapted to the Sea of Marmara, which has a unique two-layered water system.  相似文献   

19.
Abstract

The rich and relatively diverse fossil mammalian assemblage from Gökler is of special importance for understanding of faunal evolution in Central Anatolia. Large mammals were not recovered, but insectivores and rodents are abundant. The assemblage of rodents is studied in detail and comprises mainly diversified cricetids. Dormice are abundant, but are represented by only one species. Squirrels are represented only by few specimens and also beaver remains were identified. Spanocricetodon sinuosus is referred to a new genus Latocricetodon nov. gen that is tentatively assigned to the Pseudocricetodontinae. Newly named species are Cricetodon goklerensis sp. nov., Democricetodon haltmari sp. nov., Eumyarion lukasi sp. nov. and Glirudinus matusi sp. nov. The rodent assemblage is assigned to local zone C which is correlated to the European biounit MN2 (early Miocene). Our biochronological assessment is supported by radiometric dating from two volcanic ash layers.

Latocricetodon

LSID http://zoobank.org/urn:lsid:zoobank.org:act:3414DB1E-0C5E-4154-BE5E-02A9ED183B1A

Cricetodon goklerensis

LSID http://zoobank.org/urn:lsid:zoobank.org:act:1B658872-6C10-4355-B87C-3E6277AF4EDA

Democricetodon haltmari

LSID http://zoobank.org/urn:lsid:zoobank.org:act:9B13F956-7F8C-406A-9970-1F5E999E54C6

Eumyarion lukasi

LSID http://zoobank.org/urn:lsid:zoobank.org:act:34DED87E-855F-4969-AB84-10BED5C572BF

Glirudinus matusi

LSID http://zoobank.org/urn:lsid:zoobank.org:act:798ECB9A-E3B5-4C38-B5B3-FEB17AF734FE  相似文献   

20.
Atmospheric pollen was collected with a Burkard spore trap in Ankara, Turkey, from January 1990 to January 1993. A total of 135.787 grains/m3 belonging to 47 taxa were observed. The local pollen season started in February in 1990 and 1991 and in March in 1992. Relatively low pollen concentrations were recorded in 1990 and 1992, probably because of precipitation and low wind speed in the spring. A relatively high pollen concentration was recorded in 1991 which could be caused by higher wind speed in the spring and more precipitation during the winter. Cupressaceae/Taxaceae, Pinaceae, Gramineae, Betula, Moraceae, Platanus, Populus, Acer, Quercus, Chenopodiaceae/Amaranthaceae, Plantago, Rumex are found to be the dominant pollen types in the atmosphere in Ankara. The pollen composition generally reflects the vegetation of gardens, parks and roadsides, while the natural steppe vegetation of the area around Ankara is not properly represented.  相似文献   

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