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1.
New earthworm samples from Cyprus are assessed and discussed. A re-evaluation of specimens previously relegated to the Southern Alpine species Perelia nematogena (Rosa, 1903), revealed two independent species: Perelia phoebea (Cognetti, 1913 Cognetti, L. (1913): Escursioni zoologiche del Dr. E. Festa nell’Isola di Rodi V. Oligocheti. Bollettino dei Musei di zoologia ed anatomia comparata della R. Università di Torino, 28, 16. [Google Scholar]) ,described originally from Rhodes Island, (Greece) and an undescribed species Perelia makrisi sp. n. The new species is similar also to the Levantine Pe. galileana Csuzdi &; Pavlí?ek, 2005 and corroborates the hypotheses that the autochthonous earthworm fauna of Cyprus is of Levantine origin.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:FD1996DC-2FFC-42D5-A1D2-005B50E6FC64  相似文献   

2.
A review of the earthworm fauna of the Carpathian Basin recorded a total of 97 earthworm species of which three: Dendrobaena vladeasa, Octodriloides izanus and Octodrilus parvivesiculatus spp. nov. are new to science. A biogeographic analysis of the earthworm fauna revealed an extraordinarily high rate of endemism (40.21%) which is explained by the special Quaternary and tectonic history of the region.  相似文献   

3.
Leposoma is a conspicuous component of leaf litter herpetofauna of South and Central American rainforests. The 15 bisexual and one parthenogenetic species are allocated to the parietale and scincoides groups based on morphology. Phylogenetic analyses of 1830 bp (mtDNA + nuclear) were performed on 63 specimens of four species from Amazonian and Panamanian rainforests, and six species and one undescribed form from the Atlantic Forest. Different methods of tree reconstruction were explored, with Anotosaura vanzolinia and Colobosauroides cearensis as outgroups. The monophyly of the parietale and scincoides groups is strongly supported. Contrary to previous hypotheses suggesting a recent contact between Atlantic and Amazon forests, our estimates point to an initial split in Miocene. The position of Leposoma baturitensis, endemic to relictual forests in the semiarid Caatingas northeastern Brazil, and its divergence from the remaining species of the Atlantic Forest, suggests an ancient isolation with no indication of a secondary contact with forests of the eastern coast. Our data do not permit unambiguous assignment of parental species of the unisexual Leposoma percarinatum or the mechanism involved in the origin of parthenogenesis, but revealed two highly divergent diploid and triploid lineages within L. percarinatum, indicating that the unisexuals represent a species complex.  相似文献   

4.
In many species of simultaneous hermaphrodites, body size correlates with fecundity, and larger partners are preferred to small ones. Since sperm exchange is usually reciprocal, small individuals may be rejected by larger partners resulting in size-assortative mating. We studied the mating patterns in a natural population of the simultaneous hermaphroditic earthworm Eisenia fetida (Oligochaeta, Lumbricidae). We found that size-assortative mating processes existed, with variance in body weight within pairs lower than between pairs in mating earthworms. This non-random mating pattern probably reveals the existence of mate selection in this species, which lives at elevated densities with high availability of potential mates.  相似文献   

5.
Mitochondrial cytochrome oxidase II (COII) gene sequences (549 base pairs) were used to investigate the taxonomic relationships among 12 marmoset (Callithrix, Cebuella and Mico) taxa. A large number of substitutions were found in the third base codon positions, providing a strong phylogenetic signal in a gene coding a conserved protein. Despite the significant affinity between the 2 Amazonian genera Cebuella and Mico, found in recent molecular studies, the analysis presented here did not resolve convincingly the phylogenetic relationships between the 3 genera. Mico nevertheless formed 3 distinct clades, reflecting a basic division of species groups based on geographic distribution (east or west of the Rio Tapajós) rather than morphology (presence or absence of auricular hair). This supports the taxonomic distinction of the allopatric emiliae forms. In Callithrix, Callithrix aurita forms a distinct clade, but the remaining morphotypes form a somewhat contradictory cluster, possibly resulting from an extremely rapid radiation.  相似文献   

6.
Abstract The introduced earthworms, Aporrectodea trapezoides and Aporrectodea caliginosa, are common in agricultural soils in southern Australia. The seasonal abundances of these species were monitored in five pastures in the Mount Lofty Ranges, South Australia. Highest numbers occurred from winter to early spring: densities of up to 407 and 446 m?2 were recorded for A. trapezoides and A. caliginosa, respectively. Adults were restricted to winter and spring, when breeding occurred. Subadults and juveniles survived summer. Aporrectodea trapezoides and A. caliginosa were abundant in the surface layers of the soil (0–10 cm depth) for between 3 and 7 months (autumn to spring), when soils were moistest. During summer, most individuals were found > 20 cm below the surface where they were inactive, coiled tightly within sperical chambers. The abundance of A. trapezoides and A. caliginosa varied within and between pastures. Numbers were lowest where the clay content of the soil was low. A dipteran parasite attacked a small proportion of A. trapezoides at one site in spring.  相似文献   

7.
The earthworm Octodrilus complanatus (Dugès, 1828) is a large-sized species often found in grasslands and pastures, with a wide distribution area in Europe and North Africa. In order to determine the characteristics of its life cycle, earthworms of this species were cultured from hatching until they reached maturity. Development rates, cocoon production, and incubation period were recorded under controlled conditions. On average, individuals of O. complanatus reared in isolation from hatching reached maturity at day 150 and body weight at maturity ranged between 6 and 8 g. The cocoon incubation period was 66 days, and only one individual hatched from each cocoon, with a mean hatchability of 55%. Reproductive rate showed by O. complanatus after mating was of 52 cocoons per earthworm per year. The results showed that the life cycle of O. complanatus was characterized by both low growth rates and low fecundity. Specific features in life history traits of O. complanatus were compared with those of species of the genus Octodrilus and other related earthworms.  相似文献   

8.
Distribution of frequencies alleles of polymorphous loci of peroxidase (Pox), leucineaminopeptidase (Lap), phosphoglucomutase (Pgm) and octanoldehydrogenase (Odh) were studied by electrophoresis in polyacrylamide gel in 22 local samples of Esenia foetida in Russia (European part), Ukraine, Kazakhstan and Kirghizia. The samples form two spatial groups--"northern" and "southern", distinguished by set of alleles in every studied locus. The "northern" groups is formed by local populations of European Russia from Murmansk region on the north to Smolensk region on the south, and also by cultivated population of selection line "red California hybrid". The "southern" group is formed by local populations on the territory of Russia from middle Volga to the North Caucasus, Ukraine, Kazakhstan, Kirghizia, cultivated populations from Kirghizia and Portugal. High degree of genetic difference between samples and independence of alleles frequencies distribution from geographical location and habitat allows to consider almost all studied groups as separate populations. Statistical processing of Nei genetic distances (Nei, 1972) revealed reliable differences between averages of within- and intergroup distances. Besides, discrete differences between intervals of significance of genetic distances were revealed. The results indicate that on the studied territory E. foetida has hierarchical two level structure. The first level is formed by local populations differed by frequency of the same alleles. The second level is formed by local populations, united into spatial groups, that are qualitatively distinguished by the set of alleles in the same loci.  相似文献   

9.
10.

Background and Aims

Species'' boundaries applied within Christensonella have varied due to the continuous pattern of variation and mosaic distribution of diagnostic characters. The main goals of this study were to revise the species'' delimitation and propose a more stable classification for this genus. In order to achieve these aims phylogenetic relationships were inferred using DNA sequence data and cytological diversity within Christensonella was examined based on chromosome counts and heterochromatin patterns. The results presented describe sets of diagnostic morphological characters that can be used for species'' identification.

Methods

Phylogenetic studies were based on sequence data of nuclear and plastid regions, analysed using maximum parsimony and maximum likelihood criteria. Cytogenetic observations of mitotic cells were conducted using CMA and DAPI fluorochromes.

Key Results

Six of 21 currently accepted species were recovered. The results also support recognition of the ‘C. pumila’ clade as a single species. Molecular phylogenetic relationships within the ‘C. acicularisC. madida’ and ‘C. ferdinandianaC. neowiedii’ species'' complexes were not resolved and require further study. Deeper relationships were incongruent between plastid and nuclear trees, but with no strong bootstrap support for either, except for the position of C. vernicosa. Cytogenetic data indicated chromosome numbers of 2n = 36, 38 and 76, and with substantial variation in the presence and location of CMA/DAPI heterochromatin bands.

Conclusions

The recognition of ten species of Christensonella is proposed according to the molecular and cytogenetic patterns observed. In addition, diagnostic morphological characters are presented for each recognized species. Banding patterns and chromosome counts suggest the occurrence of centric fusion/fission events, especially for C. ferdinandiana. The results suggest that 2n = 36 karyotypes evolved from 2n = 38 through descendent dysploidy. Patterns of heterochromatin distribution and other karyotypic data proved to be a valuable source of information to understand evolutionary patterns within Maxillariinae orchids.Key words: Chromosome number, Christensonella, Cymbidieae, cytotaxonomy, fluorochrome staining, Maxillaria, Maxillariinae, molecular phylogenetics, species delimitation  相似文献   

11.
Cold hardiness of 12 species and 2 subspecies of earthworms from Northern Eurasia was studied. Supercooling temperatures, the water content and the thresholds of tolerated temperatures of worms and their cocoons were determined. The threshold values varied within ?1…?35°C for worms and within ?1…?196°C for cocoons. Earthworms of 4 species and 2 subspecies survived freezing. Cocoons of all species except Eisenia fetida possessed a protective dehydration mechanism which prevented their freezing. During wintering at subzero temperatures, earthworms lost up to 20% of water, cocoons up to 37%. Species of the same life form can overwinter at different phases and have different cold hardiness values. On the whole, epigeic and epi-endogeic species (except for Eisenia fetida) were more resistant to cold than endogeic ones. The following preliminary classification of earthworms according to their tolerance to negative temperatures is proposed: (1) both onthogenetic phases are tolerant; (2) only cocoons are tolerant; (3) both onthogenetic phases are intolerant. The geographic distribution of all the studied species (except for Eisenia nordenskioldi nordenskioldi) is partially or completely limited by insufficient resistance of the worms to negative temperatures. A significant cold hardiness of cocoons of most species is nonadaptive, since the worms hatched from the eggs in spring die without having enough time to reach maturity and to lay cocoons before the onset of subzero temperatures. Only 3 species (Eisenia nordenskioldi nordenskioldi, Eisenia atlavinyteae, and Dendrobaena octaedra) can live in permafrost regions; this is the main reason for a drastically reduced diversity of earthworm assemblages in eastern Siberia except for its southern, mountain parts. In general, the reasons for the impoverishment lie in the modern climatic conditions correlated with the ecophysiological capacities of earthworms.  相似文献   

12.
13.
The species composition, population structure, and synecological characteristics of earthworms inhabiting forest and meadow formations of unique beech–hornbeam woodland of the Karasu River basin have been studied. Thirteen Lumbricidae species were found. The species composition and earthworm population structure depend on phytocenosis edificators. The greatest diversity, namely, species, chorological, and ecological, was recorded in soils of relict beech phytocenosis. It was shown that in the case of forest clearing its earthworm’s fauna remains intact. In the secondary meadows, the following was noted: the lowest species diversity of Lumbricidae, domination of soil species proper, and dramatically increasing diversity indices compared to forest associations.  相似文献   

14.
The distribution of polyploid races of earthworms in the East European plain and Siberia was analyzed. Amphimictic autopolyploid races of two species of the Asian genus Eisenia, E. nordenskioldi and E. atlaviniteae, are widespread in Siberia, from its southern boundary to the arctic region, while polyploid Lumbricidae in the East-European plain, except for the Volga region, are represented mainly by parthenogenetic forms of other genera. This is presumably related to differences in the Pleistocene environmental history between the two adjacent geographic regions of Eurasia.  相似文献   

15.
In order to assess the response of epigeic earthworms to seasonal changes we monitored the population dynamics of Eisenia fetida (Oligochaeta, Lumbricidae) in a manure heap in the field during a year. Earthworms were hand-sorted from five 0.25 x 0.25 x 0.20 m blocks around the heap in November (autumn) 1999 and in January (winter), April (spring) and August (summer) 2000 to determine earthworm population dynamics. Earthworms of each block were classified into different age classes: mature, preclitellate, juvenile, hatchling and cocoon, and afterwards counted and weighed. Seasonality had a strong effect on the density, biomass and reproductive activity of the population. The population of E. fetida was characterized by a high density of individuals and the predominance of mature individuals throughout the year. Maximum density, mating activity and size of cocoons were achieved in spring, but there were not changes in the number of cocoons per mature earthworm throughout the year. Unexpectedly, the smallest cocoons were produced in winter by the largest individuals. These results suggest that E. fetida is able to allocate resources to growth and/or reproduction in response to environmental fluctuations.  相似文献   

16.
Cardoso A  Vogler AP 《Molecular ecology》2005,14(11):3531-3546
Species delimitation is complicated where morphological variation is continuous or poorly subdivided, but for taxonomic convenience it is common practice to separate and name geographical groups to capture this variation. DNA-based approaches may be used to test if these groups in fact represent historically divided, discrete species entities. The Cicindela hybrida complex (Coleoptera: Cicindelidae) is an assemblage of up to seven morphologically recognized species and 15 subspecies with wide distribution in the Palaearctic region. We sequenced a discontinuous segment of 1899 bp of mtDNA including three regions (coxI, rrnL+trnL2+nad1, cob) for a total of 99 specimens from 36 sampling localities across Europe, revealing 48 haplotypes. Four major clades could be identified corresponding to geographical groups from central Iberia, Ukraine, central Europe, and a band from the Atlantic Iberian coast to northern Europe. Taking into account further subdivisions within these clades, four of the six named species included in the analysis were recognizable by applying various procedures for species delimitation. Age estimates from calibrated molecular clocks date the diversification of the hybrida group within the past 2 million years (Myr), and the separation of the northern clade within 0.4 Myr. Nested clade analysis revealed the rapid range expansion of the northern group consistent with postglacial dispersal, but we did not find support for specific source population(s) in the postulated southern refugia. The evolutionary framework based on mtDNA sequences is shown to identify species entities as discrete clusters of closely related sequences and provides an objective system for delineating and recognizing hierarchically structured groups. In the case of the C. hybrida complex, these groups largely coincided with those established from morphology. The study adds further support to the utility of mtDNA-based sequence profiles (the 'DNA taxonomy') as a rapid and objective synthesis of evolutionary diversity and as reference system for communication.  相似文献   

17.
Caprines include all bovids related to sheep and goat. The composition of the group is controversial and inter-generic relationships have been widely debated. Here, we analysed 2469 characters draw from three distinct molecular markers, i.e. two mitochondrial genes (cytochrome b and 12S rRNA) and one nuclear fragment (exon 4 of the κ -casein gene). The taxonomic sampling includes all genera putatively described as caprines, as well as several other bovid genera in order to elucidate the position of caprines within the family Bovidae, and to determine the exact composition of the group. Phylogenetic analyses confirm firstly that Pseudoryx and Saiga do not belong to caprines, and secondly, that all tribes classically defined in the literature are not monophyletic, supporting the inclusion of all caprine species into a unique enlarged tribe Caprini sensu lato . Our results are in contradiction with previous investigations suggesting a sister-group relationship between Ovis (sheep and mouflons) and Budorcas (takins). By using a molecular calibration point at 18.5 Mya for the first appearance of bovids, we estimated divergence times with our molecular data. We also performed biogeographic inferences to better understand the origin and diversification of caprines during the Neogene. Our analyses suggest that caprines shared a common ancestor with Alcelaphini and Hippotragini in the middle-late Miocene (13.37 ± 0.70 Mya). Our results also indicate that the extant generic diversity of caprines resulted from a rapid adaptive radiation during the late Miocene, at 10.96 ± 0.73 Mya. We propose that this adaptive radiation resulted from the acquisition of reduced metacarpals, a key innovation which occurred during the late Miocene as a consequence of insularity isolation in the mountainous mega-archipelago between Mediterranean and Paratethys Seas.  相似文献   

18.
The Leptynia hispanica stick insect species complex includes bisexuals, triploid and tetraploid parthenogenetic populations, suggesting that polyploidy has played a central role in the evolution of this complex. An analysis of karyotype, mitochondrial DNA (cox2) and nuclear DNA (ef1-alpha) markers was carried out to clarify phylogenetic relationships and microevolutionary/phylogeographical patterns of the L. hispanica complex. Our analyses suggested a subdivision of bisexual populations into four groups, tentatively proposed as incipient species. Moreover, triploids and tetraploids showed two independent origins, the latter being more ancient than the former. From ef1-alpha analysis, triploids showed hybrid constitution, while the hybrid constitution of tetraploids is likely, but more data are needed. We suggest that L. hispanica is a case of 'geographical parthenogenesis' with parthenogenetic strains colonizing large peripheral ranges, and bisexuals confined to glacial refuge areas. Moreover, the age, wide distribution and competitive advantage of polyploids over diploids, demonstrate their significance in the evolution of the L. hispanica species complex.  相似文献   

19.
The genetic diversity of Lumbricus rubellus Hoffm. earthworms collected in different parts of the Moscow and Kiev regions was studied by means of electrophoresis in polyacrylamide gel, using the loci encoding unspecific esterases and generic proteins as biochemical-genetic markers. A considerable diversity of samples in all alleles of these loci was revealed. With respect to allele frequencies of the locus My1, the samples from the Moscow and Kiev regions formed two genetically distinct spatial groups. Within these groups, the samples were genetically heterogeneous, and each of them could be regarded as an individual population.  相似文献   

20.
? Premise of the study: Despite its small size, New Caledonia is characterized by a very diverse flora and striking environmental gradients, which make it an ideal setting to study species diversification. Thirteen of the 19 Araucaria species are endemic to the territory and form a monophyletic group, but patterns and processes that lead to such a high species richness are largely unexplored. ? Methods: We used 142 polymorphic AFLP markers and performed analyses based on Bayesian clustering algorithms, genetic distances, and cladistics on 71 samples representing all New Caledonian Araucaria species. We examined correlations between the inferred evolutionary relationships and shared morphological, ecological, or geographic parameters among species, to investigate evolutionary processes that may have driven speciation. ? Key results: We showed that genetic divergence among the present New Caledonian Araucaria species is low, suggesting recent diversification rather than pre-existence on Gondwana. We identified three genetic groups that included small-leaved, large-leaved, and coastal species, but detected no association with soil preference, ecological habitat, or rainfall. The observed patterns suggested that speciation events resulted from both differential adaptation and vicariance. Last, we hypothesize that speciation is ongoing and/or there are cryptic species in some genetically (sometimes also morphologically) divergent populations. ? Conclusions: Further data are required to provide better resolution and understanding of the diversification of New Caledonian Araucaria species. Nevertheless, our study allowed insights into their evolutionary relationships and provides a framework for future investigations on the evolution of this emblematic group of plants in one of the world's biodiversity hotspots.  相似文献   

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