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1.
In compliance with the 1981 Sydney Code of Botanical Nomenclature, the combinationSalvia dorrii var.incana (Benth). Strachan is made for what has previously been calledS. dorrii var.carnosa (Greene) Cronq.  相似文献   

2.
Jamesia (Hydrangeaceae) is endemic to western North America from the southern Rocky Mountains in southeastern Wyoming and Colorado west across the Great Basin to the southern Sierra Nevada and south through New Mexico and southeastern Arizona to Chihuahua and Nuevo León. Its distinctiveness and Oligocene fossil record suggest that it is an old genus. The genus comprises five geographically distinct taxa that can be grouped into two species. One of these,Jamesia americana, is further divided into four varieties, the second of which is new, and the fourth of which assumes a name older than that in current use:J. americana var.americana, var.zionis, var.macrocalyx, and var.rosea. The second species,J. tetrapetala, is new.  相似文献   

3.
The goldspotted oak borer, Agrilus auroguttatus Schaeffer, is an invasive woodborer in California USA that is native to oak woodlands across southern Arizona USA. Developing a classical biological control program for this pest in southern California is a high priority due to the continuing ecological and economic damage caused by this insect since its recent introduction into the area. In an attempt to determine the area of origin for this invasive beetle, analyses of the mitochondrial cytochrome oxidase and ribosomal nuclear D2 domain of the 28S gene regions were undertaken and provided insight into the phylogeographic relationship between and within populations of A. auroguttatus in Arizona and California. The area of origin for the invasive population of goldspotted oak borer in California was not determined conclusively, although our molecular data suggests the Dragoon Mountains in Cochise Co., Arizona as a possible source for the California population of A. auroguttatus. Results also confirmed that individuals collected from populations across southern Arizona and California are all A. auroguttatus, and are not part of a cryptic species complex comprised of the morphologically similar A. coxalis. Future surveys for natural enemies of A. auroguttatus will focus on the Dragoon Mountains as a potential source for co-evolved enemies for use in a classical biological control program against this invasive woodborer in southern California.  相似文献   

4.
The following ten new species of the ant genus Temnothorax are described and illustrated: T. anaphalantus (California, Baja California), T. arboreus (California), T. caguatan (Oregon, California, Baja California), T. morongo (California, Baja California), T. myrmiciformis (California, Baja California), T. nuwuvi (Nevada), T. paiute (California, Nevada), T. pseudandrei (Arizona, California), T. quasimodo (California) and T. wardi (California). A key to workers of the twenty-two Temnothorax species known or expected to occur in California is provided.  相似文献   

5.
Two desert shrubs belonging toEriogonum subgen.Eucycla sect.Corymbosa are described from southern Utah and northern Arizona.Eriogonum mortonianum, endemic to red clay hills southwest of Fredonia, in extreme northeastern Mohave County, Arizona, is most closely related toE. smithii, a species endemic to the San Rafael Desert of Emery County, Utah, but differs in having wider leaves, a much more branched inflorescence, and smaller, pale-yellow or white flowers.Eriogonum leptocladon var.papiliunculi, found in central Garfield and eastern Kane counties, Utah, southward into northern Coconino and Navajo counties, Arizona, is distinguished from var.leptocladon by its white flowers and from var.ramosissimum by its glabrous stems.  相似文献   

6.
Epidemics of wheat stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), are more frequent in the regions where Pst can oversummer and overwinter. Regions for potential oversummering and overwintering of Pst were determined in the contiguous United States using a survival index (SI) ranging from 0 (most unfavorable) to 10 (most favorable) developed based on long-term weather data. The pathogen can survive in cool summer in the most regions north of latitude 40°N, particularly Washington, Idaho, Montana, Oregon and California. Due to limiting high temperatures, it survives marginally during summer in Arkansas, Delaware, Georgia, Iowa, Illinois, Indiana, Kansas, Kentucky, Massachusetts, Missouri, Ohio, Oklahoma, Rhode Island and Texas. Similarly, unfavorable hot summer restricts summer survival of the pathogen in the most regions south of 40°N except for highlands in the Rocky or Appalachian Mountains. Warm winters favor fungal survival in most regions south of 40°N and the Pacific Coast, including Alabama, Arkansas, Arizona, California, Florida, Georgia, Idaho, Louisiana, Mississippi, New Mexico, Nevada, Oregon, South Carolina, Texas and Washington. Severe winters do not allow survival in most regions north of 40°N and east of the Rocky Mountains, whereas less severe winter in Delaware, Illinois, Indiana, Kansas, Kentucky, Massachusetts, Maryland, Michigan, Missouri, North Carolina, New Jersey, New York, Ohio, Oklahoma, Pennsylvania, Rhode Island, Tennessee, Utah and Virginia permits marginal survival of Pst. Most wheat-growing regions have climatic suitability for either oversummering or overwintering. Both oversummering and overwintering can occur in the Pacific Northwest (Idaho, Oregon and Washington), Arizona, California, North Carolina, New Mexico, Pennsylvania, Virginia and West Virginia. These regions may provide primary inoculum for stripe rust epidemics in their own and surrounding regions.  相似文献   

7.
Study ofChenopodium incanum has revealed considerable variability in what has been viewed previously as a uniform species. Variation is correlated with geographic distribution, and thus two new varieties are described. Varietyeatum Crawford occurs in western Texas, southern New Mexico and southern Arizona, whereas var.occidentale Crawford is restricted to the Great Basin and Mohave Desert. The var.incanum grows primarily on the western Great Plains and eastern slopes of the Rocky Mountains. Morphological features serving to distinguish the varieties are presented and discussed. Also considered are the characters that allow the separation ofC. incanum andC. fremontii.  相似文献   

8.
Four flavonoid geographical races based on twenty flavonol 3-O-glycosides were found to exist in Chenopodium fremontii with those populations from the northern part of the range (northern Colorado, Wyoming. and western Nebraska) producing 7-methyl ethers and 3-O-galactosides and glucosides. Plants from Arizona. southern Colorado and New Mexico lack 7-methyl ethers and contain 3-O-rhamnogalactosides and rhamnoglucosides (rutinosides). California populations are chemically similar to those from Arizona, southern Colorado and New Mexico but contain arabinosides while lacking rutinosides. No morphological features could be correlated with the chemical races. Chenopodium fremontii can be distinguished chemically from other closely related diploid species of the western U.S., all of which exhibit simpler flavonoid patterns. It is suggested that the simpler chemical patterns for the latter species (which include C. atrovirens, C. desiccatum, C. hians. C. incanum, C. leptophyllum, and C. pratericola) are a derived condition relative to C. fremontii.  相似文献   

9.
The breeding grounds of migrant generation monarch butterflies in eastern North America are well known. In stark contrast the location of natal grounds of western migrants has not been delineated. We show that 55% of the area within seven western states was potential breeding range based on: (1) the occurrence of milkweed host plant species with phenology making them available during late-summer and (2) regional thermal conditions supportive of adult reproductive activity and development of immature stages. We next used a series of spatially explicit “bottom-up” regression models to test this first-approximation natal origins distribution. We tested for associations between variation in moisture availability at putative natal habitat and inter-annual variation in monarch abundance at western wintering sites for a 10 year period (1998–2007). Variation in moisture availability, as measured by Palmer’s drought severity index (PDSI), across the western region predicted monarch abundance patterns. In contrast and as expected, PDSI across known eastern breeding grounds did not predict variation in western monarch migrant abundance. The pattern of moisture availability was not uniform between states or within states and permitted similar tests of association at a finer geographical level. PDSI for California, Idaho, Nevada, and Oregon (but not Arizona, Utah, or Washington) were each significantly associated with monarch wintering abundance patterns with California exhibiting the strongest relationship. At a more focused spatial scale we tested the local recruitment hypothesis. This is the notion that western coastal wintering monarch populations derive only from nearby coastal breeding habitat and that monarchs do not migrate from more distant natal grounds. Variation in moisture availability within a block of three contiguous central California climate divisions (Sacramento Drainage, San Joaquin Drainage, and Southeast Desert Basin) significantly predicted inter-annual abundance of migrant generation monarchs. In contrast PDSI patterns of three coastal California climate divisions, i.e., ones local to wintering sites, as well as that of climate divisions in western Nevada and Arizona did not predict variation in monarch abundance at this more focused spatial resolution. Our findings suggest that moisture regimes act as a strong bottom-up driver of monarch abundance pattern via resource availability in western USA.  相似文献   

10.
Two new taxa are described from California:Astragalus (sect.Flexuosi)shevockii from the Sierra Nevada in Tulare County representing a new subsect.Shevockiani; andA. lentiginosus var.piscinensis from an alkaline spring in Mono County. Rediscovery in Nevada of long-lostA. lentiginosus var.sesquimetralis and a new station for the same in Inyo County, California are reported.  相似文献   

11.
The mountain yellow-legged frog Rana muscosa sensu lato , once abundant in the Sierra Nevada of California and Nevada, and the disjunct Transverse Ranges of southern California, has declined precipitously throughout its range, even though most of its habitat is protected. The species is now extinct in Nevada and reduced to tiny remnants in southern California, where as a distinct population segment, it is classified as Endangered. Introduced predators (trout), air pollution and an infectious disease (chytridiomycosis) threaten remaining populations. A Bayesian analysis of 1901 base pairs of mitochondrial DNA confirms the presence of two deeply divergent clades that come into near contact in the Sierra Nevada. Morphological studies of museum specimens and analysis of acoustic data show that the two major mtDNA clades are readily differentiated phenotypically. Accordingly, we recognize two species, Rana sierrae , in the northern and central Sierra Nevada, and R. muscosa , in the southern Sierra Nevada and southern California. Existing data indicate no range overlap. These results have important implications for the conservation of these two species as they illuminate a profound mismatch between the current delineation of the distinct population segments (southern California vs. Sierra Nevada) and actual species boundaries. For example, our study finds that remnant populations of R. muscosa exist in both the southern Sierra Nevada and the mountains of southern California, which may broaden options for management. In addition, despite the fact that only the southern California populations are listed as Endangered, surveys conducted since 1995 at 225 historic (1899–1994) localities from museum collections show that 93.3% ( n =146) of R. sierrae populations and 95.2% ( n =79) of R. muscosa populations are extinct. Evidence presented here underscores the need for revision of protected population status to include both species throughout their ranges.  相似文献   

12.
Cortical oleoresin from more than 300 Douglas-fir trees sampled in over 30 localities throughout California and southern Oregon was analyzed for its monoterpene hydrocarbon composition. The results confirmed the existence of a distinct chemical race found in its pure unhybridized form throughout the Sierra Nevada as well as near Lompoc in the Purissima Hills of coastal California. Chemical features characterizing this race included near-absence of sabinene and presence of larger amounts of - and β-pinenes in the cortical essential oil. Elsewhere in California and southernmost Oregon, the Sierra Nevada race has extensively intergraded with the coastal Douglas-fir race from western Oregon, Washington, and British Columbia (var. menziesii), a race producing large amounts of sabinene and lesser amounts of - and β-pinenes. On the basis of chemical composition, the Sierra Nevada race was judged to be closer to the inland Douglas-fir races (var. glauca) than to the coastal race. Evolution of the Sierra Nevada race is explained by the emergence of the Great Basin arid regions during the PliocenePleistocene epochs which disjoined Western Douglas-fir populations from their eastern inland counterparts.  相似文献   

13.
Examination of type material ofVerbesina standleyi andCalea pachyphylla shows that the two taxa are conspecific. The older name,C. pachyphylla, has long been associated with the quite remote,C. orizabaensis. The latter is indistinguishable fromC. rupestris andC. guatemalensis; accordingly, these are placed in synonymy.Calea orizabaensis consists of two infraspecific taxa, var.orizabaensis and var.websteri; the latter is described as new.  相似文献   

14.
Mono- and sesquiterpenoids from wood and leaves of Pinus longaeva trees collected in various localities of eastern California and western Nevada were quantitatively analyzed by GLC. Concurrently the number and size of resin canals in foliage of the same trees and as well as Pinus aristata trees from Arizona, Colorado and New Mexico were determined. While some monoterpenes (mainly α-pinene and 3-carene) suggest that P. longaeva trees from the Panamint Mountains of California are P. aristata-like, the total chemical data and morphological data indicate that Panamint trees should be grouped with P. longaeva. A chemical latitudinal gradient is evidenced by the appearance of trees producing 3-carene in large amounts along the line joining the Panamint, Inyo and White Mountains of California. Pinus rzedowskii, well separated geographically and morphologically from the accepted members of subsection Balfourianae, is shown to be sufficiently distinct chemically, as to leave its suggested membership in the subsection an open question.  相似文献   

15.
Peter F. Zika 《Brittonia》2003,55(2):150-156
Juncus effusus s. str. has two native representatives on the coast of western North America. A new combination is provided forJuncus effusus subsp.pacificus, ranging from California to British Columbia.Juncus effusus subsp.austrocalifornicus is newly described from southernmost California, Arizona, and Baja California, México. It differs from subsp.pacificus by its pale sheaths, with less thickened and less overlapping margins, and its disjunct distribution. A key is provided for the subspecies ofJ. effusus in North America.  相似文献   

16.
James L. Reveal 《Brittonia》1981,33(3):441-448
Three unnamed buckwheats listed by the United States Fish and Wildlife Service in December 1980 as potentially endangered or threatened plants are formally proposed:E. crosbyae from Lake Co., Oregon;E. grande var.dunklei from San Miguel Island, Santa Barbara Co., California; andE. ovalifolium var.williamsiae from Washoe Co., Nevada. Several other species proposed by the Fish and Wildlife Service as potentially endangered or threatened (E. allenii, E. correllii, E. eremicum, E. floridanum, E. lemmonii, E. sp./sp. nov. ined. [=E.libertini], E. tumulosum, E. umbellatum var./var. nov. ined.,E. umbellatum var.minus, E. vestitum, andE. zionis var.coccineum) are discussed and evidence is given why they cannot be considered endangered or threatened under the present Endangered Species Act of 1973, as amended.  相似文献   

17.
R. Neil Reese 《Brittonia》1984,36(1):63-66
Pedicularis contorta var.rubicunda, endemic to north-central Idaho and western Montana, is formally described and illustrated. Morphological and cytological comparisons are made with the two previously described varieties ofP. contorta. Specimens appearing morphologically intermediate between var.contorta and var.rubicunda are also examined.  相似文献   

18.
ABSTRACT Conservation of the wolverine (Gulo gulo) at the southern extent of its North American range requires reliable understandings of past and present distribution patterns and broad-scale habitat relations. We compiled 820 verifiable and documented records of wolverine occurrence (specimens, DNA detections, photos, and accounts of wolverines being killed or captured) in the contiguous United States from museums, the literature, and institutional archives. We spatially referenced 729 records with areal precision ≤1 township (93.2 km2) and temporal precision ≤10 years. Historical records (1827–1960) were located primarily in the western mountains and Great Lakes region. However, our data suggest that the historical distribution of wolverines in the Cascade Range and Sierra Nevada was disjunct, contradicting previous interpretations. Our results indicate that wolverine range in the contiguous United States had contracted substantially by the mid-1900s. Current records (1995–2005) are limited to north-central Washington, northern and central Idaho, western Montana, and northwestern Wyoming. We investigated potential relations between wolverines and alpine vegetation, cold temperatures, and spring snow cover by comparing the distribution of historical wolverine records with Kuchler's potential natural vegetation types, Holdridge's climatic life zones, and EASE snow-cover maps during the latter portion of the wolverine denning period (15 Apr-14 May). In the western mountains, historical wolverine records generally occurred in or near alpine vegetation and climatic conditions, especially at the limits of their distribution in the Cascade Range, Sierra Nevada, and southern Rocky Mountains. However, the only habitat layer that fully accounted for historical distribution patterns was spring snow cover. Causal factors for the extirpation of wolverines from the southern portions of their range in the contiguous United States are unknown, but are likely related to high levels of human-caused mortality and low to nonexistent immigration rates.  相似文献   

19.
The Joshua tree,Yucca brevifolia, is distributed over parts of Arizona, California, Nevada, and Utah. A study of its steroidal sapogenins showed that the leaves contain practically none; the wood, small amounts of smilagenin; the seeds high amounts of hecogenin and tigogenin.  相似文献   

20.
The standard model for the migration of the monarch butterfly in western North America has hitherto been movement in the autumn to overwintering sites in coastal California, followed by a return inland by most individuals in the spring. This model is based largely on observational and limited tagging and recovery data. In this paper we test the model by plotting many years of museum and collection records on a monthly basis on a map of the region. Our plots suggest a movement of Oregon, Washington and other north-western populations of summer butterflies to California in the autumn, but movement of more north-easterly populations (e.g. from Idaho and Montana) along two pathways through Nevada, Utah and Arizona to Mexico. The more westerly of these two pathways may follow the Colorado River south as indicated by museum records and seasonal temperature data. The eastern pathway may enter northern Utah along the western scarp of the Wasatch Mountains and run south through Utah and Arizona. Further analysis of distributions suggests that monarch butterflies in the American West occur primarily along rivers, and there are observations indicating that autumn migrants often follow riparian corridors. More data are needed to test our new model; we suggest the nature of the data required.  © 2005 The Linnean Society of London, Biological Journal of the Linnean Society , 2005, 85 , 491–500.  相似文献   

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