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1.
《Journal of Natural History》2012,46(43-44):2735-2746
Two new Indonesian taxa are proposed in Onthophagus Latreille, 1802, illustrating the composite faunal spectrum of the Lesser Sundas (Indonesia): O. montishannoniae, a new species from Flores, and O. accedens nusatenggaricus, a new subspecies from Lombok and Flores. O. accedens Lansberge, 1883 is, with O. dux Sharp, 1875, placed in what is here defined as the dux subgroup within the subgenus Parascatonomus Paulian, 1932. The three included species‐group taxa are keyed, their status is discussed, and new records are given. The position of O. montishannoniae seems taxonomically and geographically isolated: this species has no known close relatives in the region, neither in the Lesser Sundas, nor anywhere else in Wallacea.  相似文献   

2.
《Journal of Natural History》2012,46(31-32):1939-1945
Mosquitoes of five Iranian islands in the Persian Gulf (Abu-Musa, Greater Tonb, Lesser Tonb, Kish and Qeshm), Hormozgan Province of southern Iran, were studied during 2009 (February and March) and 2010 (April, May and November). Adult mosquitoes were obtained by hand catch, total catch and night landing catch using aspirators and light traps. Larvae were collected by dipping with a 350-ml dipper. In total, 963 adults and 114 third-instar and fourth-instar larvae representing seven species belonging to four genera were collected and identified, including Anopheles stephensi Liston, Culex perexiguus Theobald, Cx. quinquefasciatus Say, Cx. sitiens Wiedemann, Cx. tritaeniorhynchus Giles, Culiseta longiareolata (Macquart) and Ochlerotatus caspius (Pallas) s.l. This is the first record of mosquitoes on the Greater Tonb, Lesser Tonb and Kish Islands.  相似文献   

3.
4.
We examined stomach contents of preserved specimens of larval Pacific giant salamander ( Dicamptodon tenebrosus ) and Cope's giant salamander ( D. copei ) collected from sympatric and allopatric stream populations. The dietary components of these specimens were used to calculate dietary overlap between the 2 species and to determine if changes in overlap existed between sympatric and allopatric populations. To statistically test overlap values, a randomization algorithm was used to construct a simulated data matrix (i.e., null model) in order to compare observed values of dietary overlap to a distribution of overlap values from the null model. Significant levels ( P < 0.05) of dietary overlap occurred in all cases of sympatry as well as allopatry. Average dietary overlap in sympatry was significantly lower than in allopatry, suggesting a dietary shift when in sympatry to reduce competition. Diet composition also differed between sympatric and allopatric populations of each species, further suggesting a partitioning of food resources by one or both species when in the presence of its congener.  相似文献   

5.
《Journal of Natural History》2012,46(10):1503-1515
Neoathyreus androsensis n.sp., is described from Andros Is. in the Bahamas and from Cayo Coco, Cuba. The new species and four other previously described species, now known to occur in the West Indies, are briefly described, keyed and figured. One species, Neoathyreus lanei (Martínez) occurs in the Lesser Antilles and also in northern South America. The four other species occurring on either Cuba, the Bahamas, or Hispaniola are closely related to each other and somewhat less so to the Neoathyreus hamifer complex, known from Mexico and Central America. A minimum of two or three over-water dispersals by ancestral forms seem to be necessary to explain the current distributions of at least some of these West Indian species.  相似文献   

6.
We used the computer program RAMAS to explore the sensitivity of an extinction-risk model for the Gila trout ( Oncorhynchus gilae ) to management of wildfires and number of populations of the species. The Gila trout is an endangered salmonid presently restricted to very few headwaters of the Gila and San Francisco river tributaries in southwestern New Mexico. Life history data for 10 extant populations were used to examine sensitivity of the species viability to changes in a variety of factors including population size, fecundity, life stage structure, number of populations, severity and probability of forest fires, and a regulated fishery. The probability and severity of forest fires and number of populations had the greatest effect on viability. Results indicate that successful conservation of Gila trout requires establishment of additional populations and reduction of the severity of forest fires through a program incorporating more frequent, but less severe, fires.  相似文献   

7.
To overview the morphological and ecological diversification within a species of phytophagous ladybird beetle Henosepilachna diekei, information concerning its distribution and host plant use was studied. This species was found widely in South East and South Asia from the Philippines through the Greater Sunda islands, a western part of Lesser Sundas, the Malay Peninsula to Sri Lanka. Mikania species (Asteraceae), Mikania micrantha in particular, were the most frequently used host plants, but some other plants belonging to Lamiaceae or Acanthaceae were also used by some local populations. Each population is possibly monophagous. According to morphological analyses, seven populations from four host plants at six sites on four Indonesian islands were grouped into two, one occurring on Java and Kalimantan (Borneo) and another on Sulawesi and Lombok, indicating that they were separated by the Wallace line. This morphological distinction was not correlated with the host plant use.  相似文献   

8.
The ability of a plant population to respond and eventually adapt to environmental stress ultimately determines that population's survival. This becomes especially significant in environments where important plant resource levels have radically decreased. Southwestern riparian areas have numerous plant species that are experiencing radical changes in water availability due to construction of dams, and thus their ability to respond to such changes is critical. One such species likely to be greatly affected by these hydrological changes is Populus deltoides var. wislizenii (cottonwood) because it relies heavily on both groundwater and river surface volume as primary water sources. Both water sources have been extremely impacted by impoundments along southwestern rivers. To understand how New Mexico populations of cottonwood may respond to environmental changes, we quantified environmental differences and characterized physiological and morphological variation among 4 cottonwood populations. Significant differences among study sites in water availability were indicated by both soil and groundwater salinity. The northernmost site, at Abiquiu, had the highest salinity levels in both soil and groundwater, followed by Bernardo, while San Antonio and Corrales sites had the lowest soil salinity. As expected, variation in physiological and leaf morphological characters existed among and within the tree populations, most likely in response to environmental factors. Midday xylem pressure potentials indicated that Abiquiu individuals suffered the greatest water stress and they also had the highest transpiration levels. Because of high specific leaf weights and high photosynthetic levels, cottonwoods at Corrales may better mitigate lower water availability. Such physiological and morphological trait variability among populations is ecologically important and may be of use in present reclamation and conservation efforts in these areas.  相似文献   

9.
Relationships within, between, and among the Anthemideae genera Sphaeromeria, Artemisia , and Tanacetum were investigated using 238 randomly amplified polymorphic DNA (RAPD) markers obtained from twenty 10-mer primers amplified on genomic DNA. Forty-one populations from 16 taxa (15 species) were studied. Jaccard's coefficient of similarity and UPGMA clustering analysis were used to construct phenograms. T tests were used to make comparisons between samples at various systematic levels. DNA markers were 75% similar for conspecific populations. Sixteen Sphaeromeria populations (5 species) showed an average interspecific similarity of 21%. Interspecific similarity among 23 Artemisia populations (8 species with 2 subspecies of A. tridentata included) averaged 27%. Two Tanacetum species (1 population each) were 89% similar. The high similarity of Tanacetum species was in the range of observed values for conspecific populations; indeed those 2 species ( T. vulgare and T. boreale ) have been considered conspecific by some authors. The 3 subgenera of Artemisia studied ( Artemisia, Dracunculus , and Tridentatae ) formed separate groups. In comparison among the genera, Sphaeromeria was 18% similar to Artemisia (more similar to subgenus Tridentatae than the other Artemisia subgenera); intergeneric comparisons of Sphaeromeria and Artemisia and Tanacetum , which supports previously established morphological distinctions. Sphaeromeria potentilloides may be misplaced in the genus Sphaeromeria based on DNA marker results. It is likely that North American Anthemideae are circumboreal derivatives of ancestral Eurasian stock and that Sphaeromeria is derived from an Artemisia -like ancestor.  相似文献   

10.
Road track surveys were a poor index of cougar density in southern Utah. The weak relationship we found between track finding frequency and cougar density undoubtedly resulted in part from the fact that available roads do not sample properly from the nonuniformly distributed cougar population. However, the significantly positive relationship ( r 2 = .73) we found between track-finding frequency and number of cougar home ranges crossing the survey road suggested the technique may be of use in monitoring cougar populations where road abundance and location allow the population to be sampled properly. The amount of variance in track-finding frequency unexplained by number of home ranges overlapping survey roads indicates the index may be useful in demonstrating only relatively large changes in cougar population size.  相似文献   

11.
Descurainia torulosa was established in 1983 based on material collected in northwestern Wyoming. The species is now known from 2 disjunct populations in southwestern Wyoming, and recent collections have expanded the known distribution within the northern portion of its range. The north-south disjunct distribution and apparent habitat differences have stimulated questions concerning the degree of relatedness between the disjunct elements to the point that the southern populations have been suggested to be a distinct taxon. Recognition of D. torulosa as a distinct species has also been questioned. This paper is based on field examination of D. torulosa populations, study of all known D. torulosa herbarium specimens, and analysis of nucleotide sequence from the internal transcribed spacer regions 1 and 2 of nuclear ribosomal DNA (ITS-1 & 2) from population exemplars. Cladistic analysis of the sequence data support our conclusion, based on morphological analysis. Northern and southern populations of D. torulosa are conspecific. Western North American Descurainia is in need of modern, critical taxonomic revision.  相似文献   

12.
Two local pierid populations in western North America showing regionally aberrant phenologies were investigated in the laboratory. Neither a partially bivoltine Pieris napi from the Sierra Nevada foothills in El Dorado County, California (surrounded by univoltine populations), nor a vernal - univoltine P. occidentalis from a foothill outlier of the Colorado Front Range (below bivoltine populations) showed unusual responses to controlled developmental regimes in the laboratory. Their unusual phenologies are hypothesized to be the product of microclimate. Failure to undergo genetic adaptation to unusual microclimates is discussed with particular reference to the presence or absence of gene flow from nearby normal populations.  相似文献   

13.
A Teotihuacán population of the Sceloporus grammicus complex was compared with other previously studied populations (Parque Nacional Zoquiapan [PNZ], Monte Alegre Ajusco [MAA], Pedregal San Angel [PSA], Cantimplora [CA], Capulín, Laguna, Paredon, Michilia, and south Texas) for variations in several life history characteristics (SVL at sexual maturity, reproductive period, ovulation and gestation time, and litter size). Mean body size at sexual maturity of females from Teotihuacán was larger than PNZ, MAA, CA, and Capulín. Reproductive period (vitellogenesis, ovulation, gestation, and birth) for the Teotihuacán population was the shortest of all populations. In the Teotihuacán population, gestation time was similar to the Capulínand MAA populations but was shorter than all other populations except the Michilia population. Embryonic development at ovulation varied among populations, with Teotihuacán and Capulín showing earlier stages (stages 1) at ovulation than all other populations. Teotihuacán, PSA, PNZ, and Texas all showed similar litter size, which were larger than Laguna, Paredon, MAA, Capulín, and CA populations. Differences in reproductive characteristics of these populations could indicate phylogenetically constrained, reproductively isolated populations, or they may be explained as merely responses to different environments.  相似文献   

14.
The classical taxon, Steganacarus (Steganacarus) magnus (Nicolet, 1855) is redescribed on the basis of topotypic material. The study and the comparison of many European and North African populations reveals a variation in the size of the anterior notogastral tectum and consequently enables another classic entity, S. (Steganacarus) anomalus (Berlese, 1883), to be put into synonymy. These two different ecophenotypes, in the authors' opinion, seem to be linked to the presence of xeric low-altitude southern environments (S. (S.) magnus f. anomala) or cool higher-altitude mid-northern environments (S. (S.) magnus f. magna).  相似文献   

15.
Diploid, tetraploid, and hexaploid populations of Atriplex canescens ( x =9) were examined for 18 isozyme systems. Of 24 interpretable loci, only one locus (Per 1 ) was polymorphic. Another locus (Per 2 ) showed a dosage effect. Genetic distance values, D, ranged from near 0 to 0.05, which are in the normal range for local species races. Results from clonal ramets gave identical results. The data and analyses support an essentially autopolyploid origin for the polyploid populations examined.  相似文献   

16.
Historic botanical surveys documented that the natural distribution of the plains cottonwood ( Populus deltoides subsp. monilifera ) was limited to semiarid drainages east of the Rocky Mountains. Recently, a number of isolated populations of plains cottonwood have been found along the Kootenai, lower Snake, and Columbia Rivers and their tributaries. We used isozyme analysis to assess the genetic structure of these Pacific Northwest (PNW) populations in relation to native cottonwood populations east of the Rocky Mountains. These genetic data along with field surveys (dbh, age estimates) and cadastral field survey notes (mid-1800s) were used to understand the origin of these disjunct populations (i.e., relictual natives versus naturalized introductions). Genetic analyses revealed high levels of genetic diversity within and among PNW populations as well as hybridization with black cottonwood ( P. trichocarpa ). The observed range of genetic variation for PNW populations was similar to that of native cottonwood populations. Collectively, these data confirm that these scattered populations are plains cottonwood ( Populus deltoides subsp. monilifera ). Age estimates of the largest individuals found within study populations ranged from 27 to 51 years. Cadastral field surveys also noted the absence of woody vegetation along the lower Snake and Columbia Rivers. Considered together, the data suggest that these populations are of recent origin. The high levels of observed genetic variation are consistent with the reproductive biology of Populus spp. (i.e., obligate outcrossing and widespread dispersal of pollen and seed by wind and water) and a recurrent introduction of plains cottonwood throughout the study area.  相似文献   

17.
Penstemon palmeri is a short-lived perennial herb colonizing disturbed sites in semiarid habitats in the western USA. In this study seed was harvested from six native and four seeded populations during two consecutive years. In laboratory germination trials at constant 15 C, considerable between-lot variation in primary dormancy and light requirement was observed. Four weeks of moist chilling (1 C) induced secondary dormancy at 15 C. Cold-induced secondary dormancy was reversed by one week of dark incubation at 30 C. This warm incubation treatment also reduced the light requirement of unchilled, after-ripened seed. Fluctuations in dormancy and light requirement of buried seeds have been linked to seasonal changes in soil temperature. Penstemon palmeri germination responses to temperature appear to be similar to those of facultative winter annuals.  相似文献   

18.
Variation at 21 allozyme loci and 10 restriction enzymes within the mitochondrial DNA control region was assessed among 3 allopatric populations of montane vole ( Microtus montanus ) in the American Southwest. Among populations of M. montanus , the population from the White Mountains, Arizona, was most genetically divergent. Genetic and biogeographic evidence supported recognition of the White Mountains population as a distinct subspecies, M. m. arizonensis . Results also supported recognition of the Mogollon vole ( Microtus mogollonensis ) as distinct from the Mexican vole ( Microtus mexicanus ).  相似文献   

19.
Studies were undertaken to examine the degree of divergence in four populations of pika in Colorado. Separation of blood proteins was accomplished utilizing acrylamide - gel disc electrophoresis. Separate analyses of variance were carried out for the relative mobilities of two of the transferrins (designated RM &beta; 1 and RM &beta; 2 ), the mean relative distance difference of the two transferrins (DM), and the density of the most prominent albumin ( &alpha; 1 ) and transferrin ( &beta; 2 ) bands. Although the four populations were characterized by a general similarity of the gel patterns, both interpopulational and sexual variations were observed. Variations between the sexes had to do with the amounts of protein, not with differences in protein mobility. The only significant populational differences were found in reference to density and DM. The interpopulational differences may serve as an indicator of populational divergence that has not been indicated by standard morphological characters. The significant patterns of variation observed in the blood proteins of the four populations studied may reflect a lack of gene now between isolated populations.  相似文献   

20.
We investigated genetic variation within and between 3 populations of Gaura neomexicana ssp. coloradensis , a federally listed threatened species, using inter-simple sequence repeats. The data matrix included 24 individuals scored for 88 bands, with 3.4% missing data. Cluster analysis showed that members of the 3 populations are very similar and are intermixed in the phenogram. Principal coordinate analysis indicated that members of the Crow Creek population are different from the Diamond Creek and ""unnamed drainage"" populations. This could be the result of historic differences, current changes in vegetation at the Crow Creek site, or an artifact of limited sampling. In any case, for management purposes it is best to preserve the dwindling population at Crow Creek as well as the thriving populations at the other 2 sites.  相似文献   

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