首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
《Journal of Natural History》2012,46(7-8):479-488
The snakes of the genus Thermophis, including two species (Thermophis baileyi and Thermophis zhaoermii), which are found only on the Qinghai‐Xizang Plateau, were studied to determine the phylogenetic position of the genus within the broad superfamily Colubroidea. In this study, T. baileyi from two different localities in Xizang and T. zhaoermii from western Sichuan formed a monophyletic group as determined using Bayesian and likelihood methods of phylogenetic inference. Based on the nucleotide sequence of the cyt b and c‐mos genes, Thermophis appeared to be a member of the subfamily Xenodontinae, which prior to this finding had been confined to a New World distribution. The molecular data also indicate a large genetic distance between T. baileyi and T. zhaoermii, which strengthens the validity of the new species: T. zhaoermii.  相似文献   

2.
Galls found on Ephedra nebrodensis in Spain are formed by a species of Eurytoma (Hymenoptera, Chalcidoidea, Eurytomidae) which is described as new. Four other species of Chalcidoidea (two described as new) and one species of Braconidae are parasitoids or inquilines of the eurytomid. An account is given of the biology of the community of insects associated with the gall.  相似文献   

3.
《Journal of Natural History》2012,46(18):1469-1482
Three new species of octothecate Metaphire pheretimoid earthworms are described from Taiwan. They have close phylogenetic relationships with five described species, Metaphire paiwanna, Metaphire bununa, Metaphire riukiuensis, Metaphire taiwanensis, and Amynthas formosae. These eight species are all octothecate. They have similar body size, colour, prostate glands and caeca, and the seven species belonging to the genus Metaphire have C‐shaped male pores. Excluding M. riukiuensis, which has been found only in the Ryukyu Islands, the other seven species are endemic species in Taiwan. Each of them has a distinct geographical distribution. Accordingly, we inferred that the ancestor of these eight species, including M. riukiuensis, came to Taiwan from the continent of East Asia during the Pleistocene. A few of their descendants went northward to the Ryukyu Islands and were isolated. The others remained in Taiwan, dispersed, and were isolated by geographical barriers such as mountains and rivers. Subsequent allopatric speciation events in Taiwan and in the Ryukyu Islands then generated these eight species.  相似文献   

4.
Bird species density, diversity, and species richness in relation to habitat and seasonal variations were studied in the Betatakin Canyon area of Navajo National Monument, Arizona. The two most prominent habitat types are a riparian forest deep in the canyon bottom and a mature pinyon-juniper woodland on the mesas and slopes above the canyon. One hundred thirty-five species of birds were encountered during the study and recorded by season and habitat. The avifauna assemblages demonstrate definite habitat selection into groups associated with the riparian and pinyon-juniper woodland communities. Diversity, density, and species richness were greatest in the riparian habitat during the spring and summer months. The differences in bird community composition were greater between seasons than between habitats. Pinyon pine and Gambel oak were highly selected as perch sites in the pinyon-juniper and riparian areas, respectively.  相似文献   

5.
Studying animal space use patterns can help increase our understating of ecological processes such as competition and community dynamics. To quantify space and habitat use in an isolated and patchy cloud forest community in Mexico, we evaluate the vertical stratification, home range and habitat selection of two arboreal rodents: Habromys schmidlyi and Reithrodontomys microdon. Using live-traps at ground level and different forest strata, we radio-equipped nine individuals of H. schmidlyi and seven of R. microdon, and evaluated fine-scale space use and broad-scale habitat selection between cloud forest and oak forest. We found an average home range of 0.24 ha for R. microdon males and 0.72 ha for females, with a preference for higher canopy in the cloud forest. For H. schmidlyi the home range was 0.83 ha for males and 0.29 ha for females, with a preference for the understory level in the cloud forest. Home range is three-dimensional for these rodents, so we estimate that on average, individuals of both species used eight trees in the time they were tracked. We characterised the vegetation at the trap sites, and used recursive partitioning to relate the presence of different plants with the probability of finding these two species and Peromyscus aztecus, a third rodent species also present in the area and considered in our analysis of habitat use. The highest probability of finding R. microdon (96%) was related to the presence of Brachythecium occidentale and Renauldia mexicana, while H. schmidlyi (95%) was found in close proximity to Fabronia ciliaris and Everniastrum. We highlight the importance of arboreal trapping in biodiversity assessments, and the role of arboreal rodents in maintaining tropical forest ecosystems. We suggest that these rodent species could avoid or reduce competition by using the vertical strata differentially, and that H. schmidlyi and R. microdon can be biological indicators for cloud forest management and conservation.  相似文献   

6.
Summary

An account is given of seven collections of insects and spiders made in summer 1979 on snowfields above 1100m elevation in the Cairngorm mountains, Scotland. In one comprehensive collection 278 recently deposited animals representing 35 species were obtained in 25 m2; the other collections were selective. A high proportion of the roughly 700 specimens obtained have been identified. They represent at least 130 species, including 12 species of Araneae and 34 species each of Coleoptera, Hymenoptera and Diptera. Only 10 species are known to be restricted to ‘montane’ environments and it is concluded that the composition of fallout on mountain snowfields, both in Britain and elsewhere, reflects mainly the nature of the vegetation, and thus of the insect communities, in upwind areas at lower elevations. The discussion concerns the significance of fallout as a resource for high altitude communities and as a manifestation of long-distance migration and potential gene flow among populations of terrestrial arthropods.  相似文献   

7.
《Journal of Natural History》2012,46(11):1607-1625
By virtue of their low vagility, flightless insects are useful indicators of biogeographical history. Relationships of the flightless dung beetle genus, Gyronotus, are of particular interest due to its Gondwanaland ancestry, distinctive relict distribution along the south-eastern seaboard of Africa, and its restriction to forests which are seriously threatened by exploitation. Because of the limited number of diagnostic morphological characters, it was necessary to code morphometric data in order to conduct distance and cladistic parsimony analysis of interspecific relationships in Gyronotus. There was a good correlation between relationships indicated by the dendrograms/cladograms and those determined by an examination of aedeagus character states both of which indicate a disjunction between south and east African species and a broad separation between northern and southern South African species. Comparison of the bilaterally asymmetrical aedeagi of Gyronotus with the symmetrical aedeagi of the sister genus, Anachalcos Hope, suggests geographical polarization of character states from greater plesiomorphy in east African Gyronotus to greater apomorphy in South African species, particularly in the southernmost element in which the aedeagus shows extreme asymmetry. Furthermore, body shape follows a similar geographical gradient in that the three Gyronotus species of tropical east Africa are significantly more elongate than the three ovoid, lowland/afromontane species of South Africa. An examination of historical factors suggests that this spatially-restricted distribution is the relict of a very old tropical lowland pattern. In extant taxa, the phylogenetic polarization is towards one of five main centres of afrotropical forest biodiversity in the geologically old Eastern Arc and the adjoining lowland forest (Swahili centre of endemism). Survivors from old lineages may be one reason for such centres of high biodiversity.  相似文献   

8.
《Journal of Natural History》2012,46(39):3453-3470
This work is a study of the communities of oribatid mites in steppic areas of Burgos Province, central northern Spain, in relation to different habitat types belonging to natural or disturbed ecosystems. The primary objective was to find the relationship between anthropogenic use of land and several diversity indices. Parameters such as abundance, species richness, real diversity (H′) and equitability (J′) of the mite communities were calculated in 20 soil plots, sampled in spring and autumn 2000, belonging to the predominant habitat types of this area: (1) cultivated lands, (2) abandoned crop lands, (3) grasslands/pastures, and (4) natural oak forests or a pine plantation. The most widespread species in the area as well as the most abundant taxa overall are documented, together with the faunistic checklist of oribatid mites identified in the study. The results show a general decline in the composition of the oribatid community, in terms of species diversity and abundance, from non‐disturbed soils to cultivated lands. The number of species (richness) was usually higher in forest soils than in disturbed ecosystems, in which the most degraded soils showed the lowest number of species. The community analysis shows the differences due to habitat type and ubiquitous bioindicator species.  相似文献   

9.
Differences in host-plant species may affect the structure of parasitoid communities of phytophagous insects. Phytophagous insect species often consist of host races, and comparisons between host races enable us to infer the effects of host-plant differences on parasitoid communities. Here, we compare the parasitoid fauna of two host races of the leaf-mining moth Acrocercops transecta, which are associated with either Juglandaceae or Lyonia ovalifolia (Ericaceae). Field collection and subsequent laboratory rearing revealed a significantly higher parasitization ratio in the Juglandaceae race than in the Lyonia race. In the Juglandaceae race the majority of parasitoids were Braconidae, whereas in the Lyonia race the majority were Eulophidae. Furthermore, even within the same host race the most abundant parasitoid species differed between populations with different host associations. Hence, the present results strongly indicate that different host-plant taxa affect the structure of parasitoid communities even within a single phytophagous insect species.  相似文献   

10.
The parasite community of the ray Rhinoptera steindachneri from Acapulco Bay was examined and quantified; analyses were based on the sex of the host and the date of sampling. A total of 171 specimens of R. steindachneri were examined during July–August of 2010, and May and July of 2012. Twenty-one species of parasites were found: three species of Monogenea; eight adult and one larval species of Cestoda; one larval species of Nematoda; five species of Copepoda; two species of Isopoda; and one species of Hirudinea. Cestodes had the greatest species richness (43% of the total species), followed by the copepods (24%). Two species of cestode, Glyphobothrium sp. and Rhinebothrium sp., were collected only from adult rays. At the component community level, species richness showed statistically significant variation between 13 and 16 species, which is similar to previous reports for other species of rays. The parasite component communities and infracommunities of R. steindachneri exhibited similar patterns: high species number and low numerical dominance by a particular species of parasite. The differences of body size of male vs. female rays, and a change in diet and feeding behaviour with the age of R. steindachneri, are likely important factors in the structuring of their parasite communities.  相似文献   

11.
《Journal of Natural History》2012,46(7-8):481-494
Old-growth mountain forests in the Pyrenees have natural gap dynamics, a well-developed shrub layer and a large amount of dead wood. Small mammal communities in two types of old-growth forests, silver fir and mountain pine, were studied in July and September in 2006 and 2007. Four species were trapped: bank vole (Myodes glareolus), wood mouse (Apodemus sylvaticus), garden dormouse (Eliomys quercinus) and common shrew (Sorex araneus). Bank voles and wood mice were most commonly trapped (78% of all captures). There were no differences in community composition in the two forest types, although the bank vole was more often captured in the silver fir than in the mountain pine forest. Mammals were more frequently captured at trap stations with high shrub cover, high tree regeneration cover and low herbaceous cover. Our results show that forest structure and, to a lesser extent, forest type determine small mammal community structure, and specifically fine-scale occurrence patterns, in these old-growth forests.  相似文献   

12.
Basidiomes of polypore fungi host many insects. Yet systematic information about insect assemblages from most fungal species is lacking. We studied the insect community associated with the wood-decaying fungus Inonotus radiatus (Sowerby: Fr.) P. Karst. (Hymenochaetales). More specifically, we studied the effect of successional stage and weight of basidiomes, as well as shore exposition (north or south), on species richness and composition, as well as occurrence and abundance of the most abundant fungivores. Basidiomes were collected from riparian forests at five lakes in Sweden. Insects were reared out from the basidiomes in the laboratory. A total of 5645 adult insect individuals of 117 taxa were obtained. Among these, 2782 specimens of 36 taxa use Inonotus radiatus basidiomes as breeding habitat. Eight species of parasitic wasps were new to Sweden. The most abundant fungivore was Ennearthron cornutum (Ciidae), which is a generalist breeding in many polypore species. Based on our material and literature, the melandryid beetles Abdera affinis and A. flexuosa seem to be specialists on the order Hymenochaetales. Other frequent fungivores were Dorcatoma dresdensis (Ptinidae), and the lepidopterans Archinemapogon yildizae, Nemapogon cloacellus and N. picarellus (Tineidae). The parasitoid community associated with the tineid moths was similar to the community associated with the other polypore species in the order Polyporales. In contrast, the parasitoids associated with Dorcatoma (and/or Abdera) were different from the other Polyporales species, suggesting that the fungal host species is more important for these parasitoid species than the beetle host species itself. The most abundant and frequent parasitoids were the braconids Diospilus dispar and Colastes fritzeni, which both parasitise Dorcatoma. Species richness was significantly smaller in fresh than in more decayed basidiomes, but species composition did not differ. There was no difference in species composition or richness between north and south shorelines.  相似文献   

13.
The taxonomy of a complex of morphologically similar Alebra species is clarified, and the number of adult colour pattern morphs of each in Britain, and their host plant associations, established. Morphological characters are figured for the identification of the four species now recognized, including two that are associated with different species of deciduous oaks and which were previously regarded as colour pattern morphs of A. albostriella. Three nymphal colour pattern morphs are described within the A. albostriella sibling species, two of which are shared, thus supplying further evidence for their close relationship. A key is given for the identification of the species and adult morphs of Alebra in Britain.  相似文献   

14.
《Journal of Natural History》2012,46(21-22):1313-1349
ABSTRACT

Nectaries are structures that secrete a sugary solution and can occur on vegetative and/or reproductive parts of plants. The significance of floral nectaries to reward vertebrate and arthropod pollinators is well supported. The role of extrafloral nectaries (EFNs) is more ambiguous, though research has been skewed to the ant-plant mutualism. Many other insects feed at EFNs, but these interactions are vastly understudied. This study addresses the hypothesis that EFNs may influence the occurrence and structure of Neotropical canopy beetle communities. Seven canopy trees (four families) exhibiting EFNs and their associated beetles were studied over a one-year period in southern Venezuela. In total, 6818 adult beetles identified to 868 species were recorded on 25 investigated canopy tree species (#47 individuals). Of the 868 beetle species, 150 species (517 individuals; 17.3% species) from 20 families were observed drinking from foliar EFNs on seven EFN-bearing tree species. Dietary dependence on EF nectar varied, with 95 beetle species utilising this nectar within a broader diet and 55 species found feeding exclusively on EFNs. This study demonstrates unequivocally that EF nectar is a frequently utilised food resource of many beetle adults and beetles have been a significantly underestimated visitor group. A more detailed study was conducted on six individual canopy trees of two species of Chrysobalanaceae, Licania hebantha Mart. ex Hook. f. and Moquilea subarachnophylla (Cuatrec.) Sothers and Prance. In total, 115 individual adults of 64 beetle species were collected on nectar secreted on newly-sprouted leaves. These beetle assemblages were dominated by species utilising EF nectar and were associated with distinct phenological phases of the host trees. Altogether, the beetle survey found support for the hypothesis that EFNs influence the occurrence and structure of beetle communities. These beetle-EFN relationships have implications for spatial arrangement, community assembly and evolution of both host plants and beetles. Like ant-EFN mutualism, EFN-bearing trees and beetles may also form mutualism. It is possible that the plants offer easier access to a nutritious resource that may deflect herbivory of vegetative parts.  相似文献   

15.
《Journal of Natural History》2012,46(12):1825-1966
The species of Encarsia Förster (Hymenoptera: Aphelinidae) known from China are revised. This study is based largely on newly-collected material from Fujian and Guangdong provinces in mainland China, and from the island of Taiwan. A total of 76 species are treated, including 29 new species, one new combination and 16 new records for China. All species are fully described or diagnosed, and illustrated. Three new specific synonymies are proposed and two lectotypes are designated. Four species are described from males only, three belonging to the perflava-group (ancistrocera, echinocera, viggianii), having modified antennae, and one (magnivena) in the strenua-group having very unusual fore wings. A key to the Chinese species of Encarsia, based largely on females, is provided.  相似文献   

16.
《Journal of Natural History》2012,46(27-28):1705-1713
Two new species of Telema are described, from caves in Xinyi City and Cheheng County, Guizhou, southwestern China: T. feilong sp. nov., T. zhewang sp. nov. Male and female genitalia and other taxonomically important characters are illustrated. Some comparisons are made between these species and similar taxa. In addition, some notes on their ecology and the distribution of Chinese Telema are also presented. Telema are recorded from three scattered localities, Hunan Province, Guizhou Province and Hannan Province, in China.  相似文献   

17.
Bird species density, diversity, and species richness in relation to habitat and seasonal variations were studied in the Betatakin Canyon area of Navajo National Monument, Arizona. The two most prominent habitat types are a riparian forest deep in the canyon bottom and a mature pinyon-juniper woodland on the mesas and slopes above the canyon. One hundred thirty-five species of birds were encountered during the study and recorded by season and habitat. The avifauna assemblages demonstrate definite habitat selection into groups associated with the riparian and pinyon-juniper woodland communities. Diversity, density, and species richness were greatest in the riparian habitat during the spring and summer months. The differences in bird community composition were greater between seasons than between habitats. Pinyon pine and Gambel oak were highly selected as perch sites in the pinyon-juniper and riparian areas, respectively.  相似文献   

18.
《Journal of Natural History》2012,46(29-32):1965-1977
The frequency, species composition, and determinants of mixed‐species tadpole aggregations were analysed under natural conditions in a dry forest of western Madagascar. Most aggregations (73%) were formed by more than one species, with up to four species per individual aggregation. Dyscophus insularis (Microhylidae) and Aglyptodactylus securifer (Mantellidae) were the most abundant species in these aggregations. Using a logistic regression model we analysed to what extent the presence and absence of aggregations in a pond can be predicted by its biotic and abiotic habitat variables. Aggregations are more likely in deep, clear ponds with little leaf litter cover on the bottom, while the overall density of invertebrate predators in the pond seems to play a minor role. Our observations suggest that the formation of mixed‐species aggregations in tadpoles of the Kirindy Forest in our system is primarily a reaction to vertebrate predators. Therefore, aggregation behaviour may play a key role in the ability of several anuran species to utilize these spawning waters that are unpredictable in regard to the presence of fish and other vertebrates.  相似文献   

19.
《Journal of Natural History》2012,46(11):1649-1659
Four species of Encarsiella are recorded from China, including Taiwan, of which two species, E. nepalensis and E. amabilis sp. n. are new records for China. An illustrated key for their identification is provided, including the as yet extralimital species E. boswelli, which is almost certainly present in China, though currently unrecorded.  相似文献   

20.
《Journal of Natural History》2012,46(21-22):1365-1376
The relationship between myxomycetes and insects was investigated in a fragment of the Brazilian Atlantic Rainforest located in the city of Recife, Pernambuco, north-eastern Brazil. Sixteen excursions into the Dois Irmãos State Ecological Reserve (7°55′43′′ to 8°09′17′′ S, 34°52′05′′ to 35°00′59′′ W, 387.4 ha) were carried out during different seasons between August 2005 and August 2007 for observations and collections of myxomycetes and insects on decomposing trunks and leaf litter. A total of 196 specimens of myxomycetes was obtained, representing 31 species, 16 genera and six families. Baeocera sp. (Coleoptera, Staphylinidae) individuals predominated (86%) in the sample, found on the sporocarps of four species of Trichiales (Arcyria cinerea, Arcyria denudata, Hemitrichia calyculata, Hemitrichia serpula) and two species of Liceales (Lycogala epidendrum, Tubulifera microsperma). No preference was observed for type of sporocarp. No seasonal influence was found for the establishment of these associations, recorded for the first time in this forest environment.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号