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1.
A preliminary list is given of the species of the Muscidae (Diptera) of the Magadan region, including 93 species in 23 genera. Eighty-one species are newly recorded from this territory. Six species [Spilogona aenea Huckett, 1965, S. bifimbriata Huckett, 1965, S. fulvibasis Huckett, 1965, S. incerta Huckett, 1965, S. separata Huckett, 1965, S. trigonifera (Zetterstedt, 1838)] are newly recorded for Russia. All these species, except Spilogona trigonifera, are newly recorded for the Palaearctic region. The species list includes the material examined, ecological data of some species, the distribution and all known references to each species. According to preliminary estimates, this list reflects 60% of expected species in the Magadan region. Two new synonyms are proposed: Coenosia shumshuensis Shinonaga & Zhang, 2000, n. syn. for C. alaskensis Huckett, 1965, and Coenosia remissa Huckett, 1965, n. syn. for C. ciliata Hennig 1961.  相似文献   

2.
Otolith morphology is a widely accepted tool for species identification in teleost fish, but whether this holds true for very small species remains to be explored. Here, the saccular otoliths of the cryptobenthic Mediterranean clingfish Gouania (Gobiesocidae) are described for the first time. The new data, although preliminary, indicate that otolith morphology and morphometry support the recognition of the recently differentiated five species of Gouania in the Mediterranean Sea. Furthermore, otoliths of phylogenetically closely related Gouania species resemble each other more than do those of the more distantly related species.  相似文献   

3.
4.
The feeding interrelations and foraging of juvenile fish and shrimp were investigated in estuaries of Peter the Great Bay in summer and fall 2006 and 2007. In total 3483 specimens were analyzed. The trophic spectra of 34 fish species and 3 shrimp species were described for the first time. Three trophic groups were singled out depending on differences in diet compositions: (i) detritophages (3 species of bitterlings—Acanthorhodeus sp., A. chankaensis and Rhodeus sericeus, redlip mullet Liza haematocheila and two species of shrimp-Palaemon macrodactylus and Crangon cf. septemspinosa); (ii) predators (lookup Culter alburnus and Amur catfish Silurus asotus); (iii) euryphages (28 fish species and the shrimp Palaemon paucidens). The detritus food chain was found to be the primary one in estuaries of Peter the Great Bay. Most of the species had two peaks of feeding activity each day. Values of daily feeding rations were determined for 21 fish species; these varied from 1.6% to 8.0% of body weight. Similarity in diet composition was significant only for 10% of the species, which shows a low level of competition for food in the community.  相似文献   

5.
Thirty-six species of coccidia, all members of the genus Eimeria, have been described from 3 of the 9 genera and 11 of the more than 48 species in the lagomorph family Leporidae. All these are described briefly in the present paper and their synonymies are given. Coccidia have been described from the single species of Oryctolagus, from 4 of the 13 species of Sylvilagus and from 6 of the 26 species of Lepus. These genera have 12, 12, and 14 known species of Eimeria, of which only 2 are shared by Oryctolagus and Sylvilagus. Lepus has none of the coccidia of these genera. One species is known to occur in the bile ducts of the liver, 13 in the intestine, and the location of 22 is unknown. Life cycles have been determined for 9 of the species, of which 8 have been worked out in the domestic rabbit Oryctolagus and 1 in the cottontail Sylvilagus.  相似文献   

6.
B. A. Wood 《Human Evolution》2000,15(1-2):39-49
The genusHomo was established by Carolus Linnaeus in 1758. During the course of the past 150 years, the addition of fossil species to the genusHomo has resulted in a genus that, according to the taxonomic interpretation, could span as much time as 2.5 Myr, and include as many as ten species. This paper reviews the fossil evidence for each of the species involved, and sets out the case for their inclusion inHomo. It suggests that while the case for the inclusion of some species in the genus (e.g.Homo erectus) is well-supported, in the case of two of the species,Homo habilis andHomo rudolfensis, the case for their inclusion is much weaker. Neither the cladistic evidence, nor evidence about adaptation suggest a particularly close relationship with laterHomo.  相似文献   

7.
Checklist of the Anostraca   总被引:13,自引:13,他引:0  
Dento Belk  Ján Brtek 《Hydrobiologia》1995,298(1-3):315-353
In this checklist, we number the named anostracan fauna of the world at 258 species and seven subspecies oraganized in 21 genera. The list contains all species described through 31 December 1993, and those new species names made available in previous pages of this volume. The most species rich genus isStreptocephalus with 58 described species level taxa.Chirocephalus with 43,Brachinecta 35, andBranchinella 33 occupy the next three places. With the exception ofBranchipodopsis andEubranchipus each having 16 species, all the other genera include less than 10 species each. The need for zoogeographic study of these animals is demonstrated by the fact that almost 25% of the named taxa are known only from their type localities.  相似文献   

8.
Random amplification of polymorphic DNA (RAPD) was used to analyze six species, three populations, and seven regional cultivars of barley. A unique pattern of amplified DNA products was obtained for each species of the genus Hordeum.High polymorphism of barley species was revealed. Specific fragments were found in most RAPD patterns; the fragments can be used as molecular markers of corresponding species and subspecies. Several other DNA fragments were shown to serve as molecular markers of the H genome. Specific RAPD patterns were obtained for each population and each cultivar of H. vulgaresensu lato. In total, variation between the populations and between the cultivars was substantially lower than between species. Cluster analysis (UPGMA) was used to estimate genetic distances between theHordeumspecies, between the H. spontaneumpopulations, and between regional H. vulgarecultivars and a dendrogram was constructed.  相似文献   

9.
Many fagaceous species mature acorns during the second autumn after flowering and are called “2-year species.” In 2-year species of subgenus Cyclobalanopsis (genus Quercus), alternate bearing (2-year seed production cycle) is prominent, but this has not been reported for other 2-year species in the genera of Lithocarpus and Castanopsis. We tested the hypothesis that the difference in reproduction of 2-year species is linked to the weevil, Mechoris ursulus. After ovipositing on acorns, this insect cuts the shoots to which the acorns are attached. We examined the host preference of M. ursulus and reproductive traits of fagaceous 2-year species. Percentage infestation was remarkably high in the subgenus Cyclobalanopsis, whereas Lithocarpus and Castanopsis species suffered almost no damage. Furthermore, unlike Lithocarpus and Castanopsis, most of the acorn-producing shoots in subgenus Cyclobalanopsis had no current-year shoots. The clear relationship suggests that alternate bearing in subgenus Cyclobalanopsis is an adaptation to the shoot-cutting behavior of M. ursulus.  相似文献   

10.
The Drosophila willistoni group consists of 23 species of which six are sibling species and belong to the D. willistoni subgroup: D. willistoni, Drosophila equinoxialis, Drosophila tropicalis, Drosophila insularis, Drosophila pavlovskiana and Drosophila paulistorum. These sibling species are abundant in the Neotropical region and can hardly be differentiated by the usual taxonomic traits. Four of them (D. willistoni, D. equinoxialis, D. tropicalis and D. paulistorum) cover extensive geographic distribution areas overlapping in places while two of them are endemic (D. insularis and D. pavlovskiana). In this study, we presented a method for the identification of five sibling species of the D. willistoni subgroup based on the allozyme variation of acid phosphatase‐1 (Acph‐1) in acrylamide gel electrophoresis. Our work showed that Acph‐1 allozyme differences can be used for species‐diagnostic characterization. This method was shown to be a more efficient tool for species identification than others because it is both quicker and produces reliable results.  相似文献   

11.
ABSTRACT. This paper reviews the taxonomy of the microsporidia of the family Mrazekidae Léger & Hesse, 1922, based on reexamination of slides in the collection of Prof. O. Jirovec, Prague, and discusses the available type material of Mrazekia argoisi and Bacillidium criodrili. Mrazekia argoisi differs prominently from the other species, and the genus Mrazekia is restricted to this species. The aberrant cytology and development exclude the species from the phylum Microspora. The genus Bacillidium is resurrected for the type species B. criodrili and for four other species. The genus Jirovecia is retained, and five species are transferred to this genus. A new family is erected for Bacillidium and Jirovecia. As B. criodrili does not exhibit octosporoblastic, pansporoblastic sporogony, the recent taxonomic treatment of the genus Bacillidium by Issi is rejected. Mrazekia jiroveci Sprague, 1977, the new name for B. limnodrili Jirovec, 1936, is rejected.  相似文献   

12.
Cryptic diversity is common among marine macroalgae, with molecular tools leading to the discovery of many new species. To assign names to these morphologically similar species, the type and synonyms have to be examined, and if appropriate, new species must be described. The turf-forming red alga Polysiphonia scopulorum was originally described from Rottnest Island, Australia, and subsequently widely reported in tropical and temperate coasts based on morphological identifications. A recent study of molecular species delineation revealed a complex of 12 species in Australia, South Africa, and Europe. These species are placed in a taxonomically unresolved lineage of the tribe Polysiphonieae. The aim of this study was to resolve the genus- and species-level taxonomy of this complex and related species using molecular and morphological information. Three morphologically indistinguishable species of the complex were found at the type locality of P. scopulorum, preventing a straightforward assignment of the name to any of the molecular lineages. Therefore, we propose a molecularly characterized epitype. Polysiphonia caespitosa is reinstated for the only species found in its type locality in South Africa. We describe seven new species. Only one species of the complex can be morphologically recognized, with the other eight species indistinguishable based on morphometric analysis. The studied complex, together with another seven species currently placed in Polysiphonia and two Bryocladia species, formed a clade distinct from Polysiphonia sensu stricto. Based on observations of Bryocladia cervicornis (the generitype), we describe our seven new species in the genus Bryocladia and transfer another nine species from Polysiphonia to Bryocladia.  相似文献   

13.
The currently accepted type species of the genusTrichosporon Behrend isT. beigelii. This species has formerly been regarded as identical toT. cutaneum. However, these fungi are now known to represent separate species with different ecology. The first species described inTrichosporon wasT. ovoides, an agent of human white piedra. A neotype strain is designated for this species, while a lectotype strain is indicated forT. cutaneum. The nameT. beigelii is considered as doubtful and consequently cannot be maintained.  相似文献   

14.
Li  Yao-Yao  Li  Hao-Tian  Hao  Jia-Wei  Zhang  Chen-Yi  Liu  Guan-Ze  Lin  Xing-Han  Sun  Xiao-Qing  Zang  Guo-Chen  Li  Yu-Chun 《Journal of Mammalian Evolution》2022,29(3):627-643

Cryptic species are prevalent among mammals, and identifying morphological methods or measurements that can effectively distinguish cryptic species has high significance in taxonomy. Three of the white-bellied rats, Niviventer confucianus, N. fulvescens and N. huang (Rodentia: Muridae), have such similar morphological characteristics that taxonomists have not been able to effectively identify them according to their morphologies. Recent studies have determined that the N. fulvescens species complex contains multiple species, indicating that previous morphological comparisons were potentially based on inaccurate species identifications, leading to false conclusions. To clarify whether the morphological differences among these three species can be used for identification, a variety of morphological methods and measurements were combined with molecular species identification to ensure accurate identifications prior to comparing morphological characteristics. The results showed that: (1) only N. confucianus has a white tail tip, distinguishing this species from the other two species but not N. fulvescens from N. huang; and (2) the tail length of N. fulvescens and ear length of N. confucianus are greater than those of the other species. Traditional morphological methods cannot differentiate these species well, with the discrimination rate reaching more than 90%; therefore, they can only be used as auxiliary methods for morphological identification. Additionally: (3) the geometric morphological results of the four skull views can be combined to distinguish the three species, among which the discrimination rate of lateral view of mandible reaches 98%, making it effective for differentiating these species; and (4) the phallic morphologies of the three species differed significantly in the presence of a dorsal groove, thickness of the distal baculum, and the positional relationship between the distal and proximal baccula; thus, this approach can completely distinguish these species. This study examines the applicability of various morphological measurements for the identification of highly morphologically similar species, provides a reference for distinguishing cryptic species produced by convergent evolution or incomplete differentiation by morphology, and suggests that phallic morphology should be the primary characteristic for differentiating such species in the future.

  相似文献   

15.
The DNA sequences of GapC intron 8 were determined for three closely related Abies species, Abies firma, Abies homolepis and Abies veitchii, and ten alleles were identified. Although, in most cases, an allele was specifically detected in one species, some rare alleles were found in two species. The phylogenetic analysis of those alleles showed that they trace back to different ancestral sequences, and that a species possessed the different originated alleles. The polymorphism of the GapC gene observed in the three Abies species seemed to have preceded their evolutionary divergence. Received: 1 February 2000 / Accepted: 10 May 2000  相似文献   

16.
Different approaches to the study of life cycle strategies of Antarctic copepods are described in an attempt to shed new light on our present knowledge. To date, most studies were carried out on abundance, horizontal and vertical distribution and stage composition during different seasons and in various regions. Hence, the seasonal pictures had to be compiled from different years and sampling regions. The physiological method includes measurements on e.g. egg production, feeding, respiration and excretion rates, C:N and O:N ratios, lipid and protein contents. However, both physiological and biochemical data are still rare. Results of field observations are given in this paper for investigations conducted within the last 15 years in the eastern Weddell Sea, while data of physiological parameters are based on a broader geographical region. In the eastern Weddell Sea, eight copepod species account for about 95% of copepod abundance and for more than 80% of copepod biomass. Within the calanoids, the small species Microcalanus pygmaeus dominates by numbers with 66%, while the large species Calanoides acutus and Calanus propinquus comprise together 52% of the biomass. Species abundance is lowest in winter and highest in summer/autumn, however, seasonal changes in the abundance of M. pygmaeus are small and this species occurs in similar quantities throughout the year. All copepod species show a distinct seasonal vertical distribution pattern and they occur in upper water layers in summer, in contrast to the other seasons. However, the depth layers of maximum concentration differ between species. The ontogenetic vertical migration is most pronounced in C. acutus and relatively weak in C. propinquus. The age structure also shows seasonal differences with the youngest population observed in summer for C. acutus, C. propinquus, Ctenocalanus citer or autumn for Metridia gerlachei, whereas the M. pygmaeus population is oldest during summer. The youngest copepodite stage and the males are not always present in C. acutus and C. propinquus. In contrast, all developmental stages and both sexes occur throughout the year in M. gerlachei, M. pygmaeus and C. citer. Gonad maturation in the dominant calanoid species proceeds well before the onset of phytoplankton production in the eastern Weddell Sea. However, the highest portion of females with ripe gonads and hence highest egg production rates coincide with the productive period in spring and summer. In autumn, ovaries of the three larger species C. acutus, C. propinquus and M. gerlacheiare all spent. In contrast, the percentage of ripe females of the two smaller species, C. citer and M. pygmaeus, stays high in autumn. Egg production rates are highly variable within one region and species. Many copepods accumulate large depots of lipid, mainly wax esters. In contrast, five species (C. propinquus, C. simillimus, Euchirella rostromagna, Stephos longipes and Paralabidocera antarctica) almost exclusively synthesise triacylglycerols and not wax esters. The lipid content exhibits distinct seasonal patterns, and is highest in autumn. A seasonal difference is also obvious in metabolic activities with lowest rates during the dark season. The adaptation to the pronounced seasonality in the Southern Ocean differs greatly between copepod species, and most Antarctic copepods stay active during the dark season. Calanoides acutus seems to be the only true diapause species. Calculations of summer developmental rates and winter mortality rates of the large species C. acutus and C. propinquus suggest that both species have a 1-year life cycle with few females overwintering and probably spawning a second time. In contrast, a 2-year life cycle is more likely in R. gigas. However, life cycle durations of all species studied are still uncertain and regional differences are very probable.  相似文献   

17.
We tested the hypothesis that within a relatively homogeneous vegetation type the spatial configuration of different plant species may be a determining factor in the composition of the soil animal communities. Six vascular plant species (Luzula confusa, Dryas octopetala, Cassiope tetragona, Salix polaris, Silene acaulis and Saxifraga opposigifolia), growing within high Arctic Saxifraga‐lichen heath vegetation, showed different distributional patterns. Luzula confusa and S. polaris were ubiquitous throughout while D. octopetala and C. tetragona had the most scattered distributions. Soil microarthropod density varied significantly among plant species from 18 000 (S. polaris) to 42 000 m?2 (S. acaulis). Few significant numerical interrelationships were found between the population densities of the different Collembola or cryptostigmatic mite species or between microarthropod densities and variation in the physical properties of the soil associated with each plant species. However, despite the high similarity of species present, Discriminant Analysis idengified distinct microarthropod assemblages associated with each plant species. Over 70% of microarthropod samples taken from soil beneath S. polaris or L. confusa were correctly classified. Rank order of animal species abundance, however, varied among plant species. The collembolan Folsomia quadrioculata ranked first in five of the six plant species but the mite Camisia anomia was numerically dominant under S. polaris. The second most abundant species was much more variable. Despite these variations, the shape of the species rank abundance curve for microarthropods was remarkably similar for all plant species, with rank one and two species comprising ca 55 and 27% of the fauna respectively. These conclusions were reinforced by χ2 analysis which idengified significantly distinct faunal communities between each plant species. Those microarthropod species contributing most to these between‐plant differences, as measured by higher or lower than expected populations, were idengified and were shown to be not always the most abundant species. Thus, on a local scale plants of different species were shown to act as useful proxy indicators of soil conditions that affect the soil microarthropod community. This should be taken into account when designing sampling programmes for soil invertebrates.  相似文献   

18.
A checklist of 137 liverwort and 445 moss species is established for Andorra based on a review of the literature and a long-term floristic survey. Five moss species, Barbula amplexifolia, Ditrichum zonatum, Grimmia donniana, Pohlia bulbifera, and P. lutescens, are new to the Iberian Peninsula. Another 7 liverwort and 156 moss species are new to Andorra. For each species, the distribution at the scale of 1?km2 and altitudinal range are documented, resulting in an improved assessment of the frequency and distribution of 101 moss species previously reported from a single record. Haplomitrium hookeri and Scapania verrucosa, which are the two Regionally Extinct species of the Spanish Red List of liverworts, occur in Andorra, which hosts between 23 and 37% of the species listed as Critically Rare, Endangered, or Vulnerable in the Spanish Red List of bryophytes. Therefore, it appears that Andorra is a key area for the conservation of the high-altitude flora of the Iberian Peninsula.  相似文献   

19.
Eichhornia azurea is a tristylous species of Pontederiaceae. Moderate self-incompatibility accompanies the floral heteromorphism of this species.Eichhornia azurea is almost exclusively visited by one bee species,Ancyloscelis gigas (Anthophoridae), in South Brazil. This species has an extremely long proboscis covered with recurved hairs. Bees use these hairs to collect pollen from the anthers placed inside the narrow perianth tube ofE. azurea. Analyses of the pollen load ofA. gigas females show that they are flower constant and carry pollen from all three anther levels. The behavior ofA. gigas and its proboscis morphology make this bee species narrowly adapted and an effective pollinator for facilitating legitimate pollination ofE. azurea flowers in southern Brazil.  相似文献   

20.
Abstract: The family Phylloporinidae was introduced in the late 19th century to accommodate a small number of Palaeozoic bryozoan genera characterized by irregularly fenestrated colonies generated by anastomosis of unilaminate branches. Among the first named of these genera were Chasmatopora Eichwald, 1855 and Phylloporina Ulrich in Foerste, 1887. The two names have been variously in fashion, and there has been confusion about whether they are subjective synonyms or are distinct genera. This taxonomic confusion has been due in large part to whether the single species (Retepora angulata Hall, 1847) assigned to Phylloporina in Foerste (1887) or the species that Ulrich intended (Retepora trentonensis Nicholson, 1875) is the type species and also because of lack of sufficient information about Foerste’s material to characterize it well. We here redescribe the pertinent species, erect the new species Chasmatopora foerstei for the species that Foerste incorrectly assigned to Phylloporina angulata (Hall), and suggest that Retepora trentonensis Nicholson be retained as type species of Phylloporina based on prevailing usage, until the issue is settled by the International Commission on Zoological Nomenclature.  相似文献   

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