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1.
History and technical literature describing potential effects of livestock grazing on mule deer ( Odocoileus hemionus ) populations and winter range habitat are reviewed. Recommendations for livestock grazing on winter ranges within the Great Basin are advanced.  相似文献   

2.
Deer mice ( Peromyscus maniculatus ) are known to larder hoard food, but their scatter-hoarding behavior is poorly documented. Eleven deer mice were each presented with 150 Jeffrey pine ( Pinus jeffreyi ) seeds in 10 γ 10- m enclosures in Jeffrey pine forests on the east slope of the Sierra Nevada. Subjects made a mean ± 1 s of 31.2 ± 30.0 caches per trial. Caches were shallow (most 2-12 mm deep) and usually contained only 1 or 2 seeds. Most caches were made at the edge of antelope bitterbrush ( Purshia tridentata ) shrubs in mineral soil or in thin layers of plant litter. These results suggest that deer mice might make a significant contribution to the dispersal of Jeffrey pine.  相似文献   

3.
《Journal of Natural History》2012,46(43-44):2795-2814
Iran’s Persian onager populations are critically endangered. This study of their natural history in Qatrouyeh National Park provides insights for enhancing their conservation. The population as a whole is greatly affected by weather. Wind, rain and cold drive populations from the plains to the valleys of hill-valley habitats. Vegetation features and water also influence habitat use, but differently for different sex and reproductive classes. Females with juveniles use plains with high-quality vegetation, whereas females without young and solitary territorial males choose those of intermediate quality. Females with young foals are also found closest to watering points. Future translocation of Persian onagers will only succeed if prospective habitats have sufficient hill-valley refuges and enough plains with winds to moderately hot conditions. Sufficient plains supporting high-quality vegetation near water for lactating females must co-exist with plains of moderate-quality vegetation that attract females without young, so reducing crowding and competition.  相似文献   

4.
Seventeen loci were examined for polymorphism in four populations of Neotoma cinerea and Peromyscus maniculatus on isolated mountain ranges in the Great Basin, one population of each in the Sierra Nevada, and one of each in the Rocky Mountains. All Peromyscus populations had higher levels of heterozygosity than syntopic Neotoma populations.  相似文献   

5.
The tropical African species of the genus Exoprosopa Macquart placed by Bezzi (1924) in his group 10, E. busiris are reviewed. A key, short diagnoses and outline distributions are provided for each species. E. albonigra Bezzi and E. saskae Szilády are shown to be synonyms of E. luteicosta Bezzi; E. engyoptera Hesse a synonym of E. brevinasis Bezzi; and E. ferrieri Hesse a synonym of E. decastroi Hesse. Two new species are described; E. selenops from Kenya and E. glossops from Nigeria.  相似文献   

6.
Summary

Three different methods of coiling the long stylets within the head capsule in the Aradidae are described; and the bearing of this on the relationships of the subfamilies is discussed.  相似文献   

7.
《Journal of Natural History》2012,46(37-38):2377-2386
The species of Bannatettix Zheng, 1993 Zheng, ZM. 1993a. One new genus and three new species of Tetriginae from Yunnan province (Orthoptera: Tetrigidae). J Shaanxi Normal Univ., 21(1): 4650.  [Google Scholar] are listed. A total of 11 species of Bannatettix Zheng were systematically researched in this paper. One new species, Bannatettix barbifemura sp. nov. is described as new to science. The distribution and an updated key to the species are presented. The type specimens are deposited in the Institute of Zoology, Shaanxi Normal University, Xi'an, China.  相似文献   

8.
9.
《Journal of Natural History》2012,46(15):1823-1840
Soil-feeding termites are dominant members of the soil fauna in lowland tropical rainforests. As ecosystem engineers, they have a profound effect on their environment, particularly through modification of the vast quantities of soil that they ingest. There is growing evidence that the processing of the soil in the gut is influenced by the enteric valve--an extremely well-developed feature in the hindgut of the Termitidae, consisting of six ridges, variously armed with spines, teeth and scales. Although this valve has been extensively used in morphological work, little is known of its function. Scanning electron microscopy has been used in this study to better understand the three-dimensional structure of the enteric valve in the Afrotropical Apicotermitinae, a group in which these valves are everted into the following chamber of the hindgut. This configuration lends itself to scanning electron microscopy in a way that it does not in other soil-feeders, since in those species the armature is obscured within the gut lumen. It seems plausible that this structure is instrumental in filtering material through the gut in such a way that the coarse, organic-poor portion of the soil is channeled fast through the centre, while directing the fine, organic-rich portion to the edges for lengthier digestion of recalcitrant plant material. Thus, the enteric valve would appear to be important for the termites to survive on this nutrient-poor but super-abundant food resource.  相似文献   

10.
Polyrhachis weaver ants build their nests from vegetation bound together using silk produced by their larvae. Here we provide a pilot study of the composition and the physical structure of three arboreal silk nests of Polyrhachis (Cyrtomyrma) delecta based on examination of three colonies. We found broadly similar nest architecture and size of the nests with each containing six or seven identifiable chambers, and describe the distribution of ants of different castes and life stages between them. We also note the construction of silk ‘girder’ structures, which spanned larger chambers, and we hypothesize that these provide additional strength to the internal nest structure. This study highlights the importance of more detailed investigation of the internal nest structure and composition in Polyrhachis, and other weaver ant species, which will help to develop our understanding of this specialized form of nest construction and nesting habits in a diverse group of ants.  相似文献   

11.
12.
Australothis volatilis sp. n., the only species of Heliothinae endemic to New Zealand, is described. The larval food plants, Vittadinia spp., are recorded and other biological information is provided. The male and female genitalia, penultimate and final instar larva, pupa, adult, native food plant, and habitat are illustrated.  相似文献   

13.
Lepidium papilliferum is an ephemeral species that occupies ""slick spot"" microhabitats in the matrix of sagebrush steppe vegetation of the southwestern Snake River plains, Idaho, USA. We related population demographic data collected from 1993 to 1996 to on-site precipitation data on the Orchard Training Area west of Boise. We also carried out field seed-retrieval and in situ seed bank studies. We found that L. papilliferum has a dual life history strategy. A fraction of each cohort sets seed as summer annuals, while the remaining plants remain vegetative and potentially biennial. Surviving biennials flower and set seed along with the annual cohort of the following year. The switch to flowering as an annual appears to be based on threshold rosette size. Probability of survival to flowering was much lower for biennials than for annuals of the same cohort, but surviving biennials sometimes had enhanced seed production. The summerdry environment of the Snake River plains combined with the slick spot habitat has apparently selected for a primarily summer annual life cycle for this species. Seeds were highly dormant at dispersal and were not responsive to dormancybreaking cues. Those from a given cohort of L. papilliferum remained viable in the soil for at least 11 years. This persistent seed bank provides a buffer against extinction in sequences of years when seed production is low or absent. Estimated seed bank size varied from near zero for a heavily disturbed site that formerly supported the species to 18 viable seeds · dm -2 for an extant population in high-quality habitat. Management for population preservation for L. papilliferum should focus on protecting the seed bank from destruction caused by livestock trampling and other anthropogenic disturbances.  相似文献   

14.
Fourteen species have either been described in, or referred to, the genus Euniphysa. Seven of these are here re-described based on type material and two new species, E. quadridentata and E. filibranchia, are described. Euniphysa oculata is found to be a subjective synonym of E. spinea, and E. unicusa is a subjective synonym of E. aculeata. Euniphysa taiwanensis and E. megalodus are correctly assigned to the genus, but cannot be described due to lack of material. Euniphysa misakiensis, E. tubicola and E. tubifex are transferred to Eunice. A key is given to the nine identifiable species retained in Euniphysa. Coding strategies for polymorphic and inapplicable characters, as well as problems associated with shared absences, are discussed. A phylogenetic analysis of Euniphysa based on 24 morphological characters yielded two most parsimonious trees (CI = 0.902, RI = 0.905). The tree topology separates Euniphysa into two distinct groups. Group I includes E. filibranchia n. sp., E. italica, E. jeffreysii, E. quadridentata n. sp. and E. spinea, it is supported by five equivocal similarities. Group II is supported by five unequivocal synapomorphies and two equivocal similarities, it includes E. aculeata, E. auriculata, E. falciseta and E. tridontesa. Based on the phylogenetic topology, Paraeuniphysa and Heterophysa are considered as junior synonyms of Euniphysa. The recognition of a separate family for Euniphysa is not warranted. All species of Euniphysa are fragile, shallow, warm water species. They have been collected mainly from sandy sediments of the Northern Hemisphere. The greatest diversity is from the South China Sea area; other species are found throughout the Indian Ocean, the Mediterranean Sea and the East Atlantic Ocean coasts suggesting the genus may have originated in the Tethys Sea. A few species have also been found in the Gulf of Mexico and the West Atlantic Ocean coast again suggesting a Tethyan origin associated with the westward drift of the North American continent.  相似文献   

15.
16.
In this study, a total of nine species of the family Psychidae were recognised from Korea. Among them, Psyche yeongwolensis sp. nov. is described as new to science. Also, a species, Proutia maculatella Saigusa et Sugimoto, is reported for the first time from Korea. All available material were dissected and illustrated. Also, an annotated catalogue of the family Psychidae from Korea is provided.  相似文献   

17.
Summary

Monthly or two-monthly samples of G. complanata were taken from the stony littoral of five unproductive lakes in N. Wales and seven productive lakes in Cheshire and Shropshire, England, over two years. Satisfactory antisera were produced against ten potential prey groups, viz. Tricladida, Oligochaeta, Mollusca, Cladocera, Asellus, Amphipoda, Chironomidae, Ephemeroptera, Plecoptera and Trichoptera. These were used in the precipitin test to identify the gut contents of the field-collected leeches.

In productive lakes Mollusca were fed on extensively followed by Oligochaeta and Chironomidae, whereas in unproductive lakes the last two prey groups were most heavily utilized. The lesser utilization of Mollusca in unproductive sites reflects lower availability. Together, these prey groups constituted 91% and 85% of the overall diet in productive and unproductive sites respectively. The other prey groups formed only small proportions of the diet with Tricladida and Cladocera being least favoured.

Dietary composition did not vary much over the course of a year. Feeding activity is low in the reproductive period and in the winter months when low temperatures prevail. There were no significant differences in resource utilization between three weight classes, viz. small, medium and large leeches.  相似文献   

18.
《Journal of Natural History》2012,46(17-18):1085-1101
A review of the genus Amphiops occurring in China is provided. A new species, Amphiops coelopunctatus sp. nov., is described from Hainan, China. Based on a study of the type material, Amphiops yunnanensis Pu, 1963, is proposed as a junior synonym of Amphiops mirabilis Sharp, 1890. Amphiops pedestris Sharp, 1890 and Amphiops annamita Régimbart, 1903 are confirmed as synonyms of Amphiops mater Sharp, 1873. Amphiops coomani d’Orchymont, 1926 is reported from China for the first time. Amphiops globus Erichson, 1843, previously reported from Macau, is found to be a misidentification. An identification key to Chinese species of the genus is provided.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:47C95EED-8B09-4BE0-A335-7E8B7CB23FE7  相似文献   

19.
20.
The present study reviews the taxonomy of the Phtisicidae (Crustacea: Amphipoda) from the coast of New South Wales, Australia. The following seven species are described; Dodecas decacentrum Stebbing, 1910b, Dodecas hexacentrum Mayer, 1903, Hircella cornigera (Haswell, 1879b), Metaproto novaehollandiae (Haswell, 1879a), Notoprotomima smithi gen. nov., sp. nov., Paraproto sp. and Perotripus sp. Generic diagnoses of Notoprotomima gen. nov., Dodecas, Hircella and Metaproto are provided based on the present materials. Notoprotomima smithi is fully described as a new species of the new genus. Dodecas decacentrum differs from Dodecas hexacentrum by the presence of paired dorsodistal projections on pereonite 2, paired mid-dorsal projections on pereonites 3 and 4 and shorter gill length on pereonites 2 and 3. Hircella cornigera and Metaproto novaehollandiae are described in detail. The larger mature males of M. novaehollandiae possess the unusual massive type of the propodus of gnathopod 2. The extended distribution of Perotripus to the New South Wales coast is noted. A key for these phtisicid amphipods from New South Wales, Australia is provided.  相似文献   

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