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1.
Schönhuth S Hillis DM Neely DA Lozano-Vilano L Perdices A Mayden RL 《Molecular phylogenetics and evolution》2012,62(1):427-446
Accurate delimitation of species is a critical first step in protecting biodiversity. Detection of distinct species is especially important for groups of organisms that inhabit sensitive environments subject to recent degradation, such as creeks, springs, and rivers in arid or semi-desert regions. The genus Dionda currently includes six recognized and described species of minnows that live in clear springs and spring-fed creeks of Texas, New Mexico (USA), and northern Mexico, but the boundaries, delimitation, and characterization of species in this genus have not been examined rigorously. The habitats of some of the species in this genus are rapidly deteriorating, and many local populations of Dionda have been extirpated. Considering the increasing concerns over degradation of their habitat, and pending a more detailed morphological revision of the genus, we undertook a molecular survey based on four DNA regions to examine variation over the range of the genus, test species boundaries, and infer phylogenetic relationships within Dionda. Based on analyses of two mitochondrial (cytb and D-loop) and two nuclear (Rag1 and S7) DNA regions from specimens collected throughout the range of Dionda, we identified 12 distinct species in the genus. Formerly synonymized names are available for two of these species, and four other species remain undescribed. We also redefine the known range of six species. The limited distribution of several of the species, coupled with widespread habitat degradation, suggests that many of the species in this genus should be targets for conservation and recovery efforts. 相似文献
2.
J. Juárez-Muñoz G. Carrillo-Castañeda R. Arreguin A. Rubluo 《Biodiversity and Conservation》2002,11(5):921-930
The species of Prosopis (Leguminosae) are welladapted to grow in the arid regions of the world. In Mexico, nearly 70%of its territory accounts for arid lands and nine species of this genus arefound in the country which are currently utilized for multiple purposes. Giventhat a sustainable exploitation of this important natural resource is necessary,knowledge of the genetic variability of natural populations is required. Thegenetic variation among and within four wild populations of Prosopisglandulosa, P. juliflora, and two ofP. laevigata, located in the Mexican States of Chihuahua(1), Sinaloa (2), Guanajuato (3) and Hidalgo (4), respectively, was determinedusing random amplified polymorphic DNA (RAPDs). There was a genetic variation of72.48% among these four populations, and within them the estimated geneticvariation was 27.52%. Between the populations of P.laevigata the genetic variation obtained was 7.15%, and within them92.85% (AMOVA, P < 0.001). Based on the assumption ofWright's island model, the genetic variation found among populations correspondsto a gene flow (Nem) of 0.09, while the gene flow detected betweenthe populations of P. laevigata was 3.2. A total of 27 RAPDphenotypes were identified in the four populations; among them, 11 correspondedto P. laevigata. The phylogenetic analyses showed that thethree species are differentiated in three clades and that probably P.juliflora was the origin of the other two species. The protogynoustrait of their flowers and the outcrossing are the main factors that may explainthe genetic variation observed in these populations. 相似文献
3.
Parker MA 《Applied and environmental microbiology》2002,68(4):2044-2048
rRNA genetic markers were analyzed in 97 isolates of nodule bacteria from six legume species in Chihuahua, Mexico. The most common genotypes were widely shared across host species and had 16S rRNA sequences identical to those of strains from an eastern North American legume (Amphicarpaea) that are closely related to Bradyrhizobium elkanii. 相似文献
4.
Matthew A. Parker 《Applied microbiology》2002,68(4):2044-2048
rRNA genetic markers were analyzed in 97 isolates of nodule bacteria from six legume species in Chihuahua, Mexico. The most common genotypes were widely shared across host species and had 16S rRNA sequences identical to those of strains from an eastern North American legume (Amphicarpaea) that are closely related to Bradyrhizobium elkanii. 相似文献
5.
Jesús Pérez-Moreno Magdalena Martínez-Reyes Angélica Yescas-Pérez Adriana Delgado-Alvarado Beatriz Xoconostle-Cázares 《Economic botany》2008,62(3):425-436
Wild Mushroom Markets in Central Mexico and a Case Study at Ozumba. More than 200 species of wild edible mushrooms are consumed in Mexico, and over 100 are sold in local, regional, and wholesale markets. This paper analyzes general trends in the commercialization of wild edible mushrooms at twelve markets in central Mexico, where at least 90 species are sold and more than 100 local names were registered. The paper then focuses its analysis on the traditional market at Ozumba (state of Mexico) near Izta-Popo and Zoquiapan national parks. In 2006, 411 stands selling more than 60 mushroom species were sampled throughout the year to record information on the vendors and the species they sold. The greatest diversity of species was recorded in July and August. More than 90% of the wild mushroom vendors were women, and 64% were 40 to 60 years old. The economic value of wild mushrooms in some regions of Mexico appears to contribute to the maintenance of traditional ethnobiological knowledge, generally observed to be in overall decline. 相似文献
6.
Marshall C. Johnston 《Brittonia》1975,27(2):119-122
Canotia, a genus of holacanthoid shrubs of southwestern United States and northern Mexico, is redescribed, and reasons are advanced for retaining it in the family Celastraceae. Two species are recognized, includingC. wendtii sp. nov. from Chihuahua. 相似文献
7.
Thomas Mione Richard C. Olmstead Robert K. Jansen Gregory J. Anderson 《American journal of botany》1994,81(7):912-918
Chloroplast DNA restriction site data were used to assess relationships among the solanaceous genera Jaltomata, Hebecladus. Old and New World Physalis, Chamaesaracha, Leucophysalis, Margaranthus, Nicandra, and Saracha, and to assess interspecific relationships within Jaltomata. Cladograms rooted with Nicotiana tabacum were constructed with Wagner and Dollo parsimony. Strict consensus trees indicate that Hebecladus originated from within Jaltomata; together these genera are monophyletic and constitute the recently circumscribed genus Jaltomata. There are two primary clades in Jaltomata: one a morphologically diverse group confined to western (largely Andean) South America, the Greater Antilles, and the Galapagos Islands; and the other a morphologically homogeneous group widely distributed from the southwestern United States to Bolivia. The controversial Leucophysalis viscosa, formerly treated as Jaltomata viscosa, is related to Leucophysalis, Physalis, Chamaesaracha, and Margaranthus; it does not group with any of the sampled species of Jaltomata. Physalis appears to be polyphyletic since P. alkekengi of the Old World branches off prior to a clade including Chamaesaracha, Margaranthus, and the two New World Physalis species sampled. 相似文献
8.
The populations of many species are declining worldwide, and conservation efforts struggle to keep pace with extinction rates. Conservation biologists commonly employ strategies such as translocation and reintroduction, which move individuals of endangered species from one part of their range to another. Because individuals from endangered populations are nonexpendable, identifying any potential barriers to the establishment of viable populations prior to release of individuals should be a priority. This study evaluates the potential for learned communication signals to constrain conservation strategies such as reintroduction in an endangered species, the Thick-billed Parrot (Rhynchopsitta pachyrhyncha). We conducted vocal surveys at three geographically distinct breeding populations in the Sierra Madre Occidental of Chihuahua, Mexico. Acoustic analyses utilizing both spectrogram cross-correlations and parameter measurements from spectrograms revealed no significant differences among the three sites in two common call types. Calls did vary among individuals within a site. The apparent lack of significant geographic variation across sampled sites suggests that differences in learned communication signals are unlikely to pose a barrier to the integration of translocated individuals from different populations into newly established populations. 相似文献
9.
10.
P. K. Bretting 《Economic botany》1984,38(4):452-463
11.
Patricia Dávila-Aranda Rafael Lira-Saade Jesús Valdés-Reyna 《Biodiversity and Conservation》2004,13(6):1101-1121
The Poaceae family includes approximately 700 genera and 10000 species, and Mexico is considered one of its most important centers of diversity and endemism. A total of 256 taxa (including 16 subspecific taxonomic units), belonging to 65 genera, are endemic to Mexico. Some of them are close relatives of important crops, while others are used in different ways all over the country. The aim of this paper is to discuss the distribution patterns at state level of the Mexican endemic species of Poaceae. Using cluster strategies, the states are classified according to their floristic similarities. Later, hotspots of endemism are identified, in order to discuss their role in conservation strategies. To evaluate the importance of each state in the conservation of the Mexican endemic Poaceae, two iterative complementarity methods were also used. Our results show that the largest concentration of endemic taxa occurs in a few states, such as Jalisco, Mexico, Michoacán, Durango, Oaxaca, Veracruz, San Luis Potosi, Chiapas, Chihuahua, Puebla, and Coahuila. The results also show that there are some patterns in the relationship to its endemism that seem to reflect important diversification trends in the family. Accordingly, 31% of the grass genera of Mexico have at least one endemic species, and 16.7% of the genera have only one endemic species. In contrast, six genera contribute 47.2% of the total number of grass endemics in Mexico. The Chloridoideae contributes 42.9% of the total grass endemic species of Mexico, whereas the Panicoideae includes 24.6%, and the Pooideae 19.8%. Thus, these three subfamilies contribute about 87% of the species endemism. On the basis of the habitat and distribution patterns of these subfamilies, two main areas of endemicity can be identified. The first area is located in warm habitats, whereas the second is related to temperate and high regions. The cluster analyses indicate the occurrence of four state groups whose phytogeographical explanation is discussed on the basis of a floristic regionalization of Mexico. The results also indicate the need to establish a relatively high number of sites and states for the conservation of 256 endemic taxa. The elevated number of sites required to conserve the Mexican endemic Poaceae is mainly due to the fact that many taxa have a restricted distribution pattern. On the basis of the patterns obtained, a few proposals are presented for undertaking the establishment of conservation priorities of these taxa. 相似文献
12.
A. Michael Powell 《Brittonia》1973,25(2):116-118
A new genus,Correllia, and its single species,C. montana, are described from Sierra Mohinora in southwestern Chihuahua, Mexico. The genus belongs in subtribe Peritylinae (Compositae tribe Helenieae) and appears to be most closely related toPerityle. 相似文献
13.
Mexico is considered a megadiverse country containing more than 10% of the world's biodiversity. The distribution of this species richness and endemism is different among the different Mexican states. We examined the species richness patterns of 13 families of vascular plants (including ferns, gymnosperms and angiosperms) in Mexico using political divisions (states) as units of analysis. We analysed the species richness values (absolute richness, endemic richness and restrictive richness) of these plant families using stepwise multiple regression analysis, assessing their relationship with a set of 10 environmental variables (expressed as heterogeneity coefficients). A combined cluster analysis with multidimensional scaling analysis (MDS) and an analysis of similarities were also undertaken to define the spatial–geographical patterns. Additionally, we proposed a methodological strategy to determine which states of Mexico have priorities for conservation. Our results suggested that the three species richness values used were significantly predicted by environmental factors, especially by climatic heterogeneity. Notwithstanding that a linear pattern was recognized, the Mexican states were gathered in four groups, which were confirmed by the MDS and the cluster analysis: (1) the Yucatan Peninsula, (2) arid Mexico, (3) the Mexican Transition Zone and (4) the megadiverse states. We proposed that 12 Mexican states include all the environmental conditions and are candidates for developing conservation programmes: (1) Quintana Roo, Tabasco and Yucatán, (2) Baja California, Chihuahua and Sinaloa, (3) Guerrero, Jalisco and Nuevo León and (4) Chiapas, Oaxaca and Veracruz. 相似文献
14.
The genus Polianthes belongs to Asparagaceae, subfamily Agavoideae (APG III, 2009) and is endemic to Mexico, spanning the states of Chihuahua and Tamaulipas in the north, and extending to the state of Oaxaca in the south. Its species are perennial, herbaceous plants with corms and bulbs. Their leaves are green or glaucous, linear or lanceolate. Inflorescences are in racemes or spikes with narrow and widely infundibuliform flowers, varying in color from white to red. The fruit is a capsule with black seeds. The number of species of Polianthes varies depending on the criteria to classify them. For example, in the first revision for the genus, Rose (1903) recognized 12 species. According to Espejo and López (1992), the genus has 15 species, whereas GarcíaMendoza and Galván (1995) reported 12 species, and Solano and Feria (2007) recognized 14 species and three varieties. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
15.
Ecological biogeography of Mexican bats: the relative contributions of habitat heterogeneity,beta diversity,and environmental gradients to species richness and composition patterns
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Celia López‐González Steven J. Presley Abraham Lozano Richard D. Stevens Christopher L. Higgins 《Ecography》2015,38(3):261-272
Mexico has higher mammalian diversity than expected for its size and geographic position. High environmental hetero geneity throughout Mexico is hypothesized to promote high turnover rates (β‐diversity), thus contributing more to observed species richness and composition than within‐habitat (α) diversity. This is true if species are strongly associated with their environments, such that changes in environmental attributes will result in changes in species composition. Also, greater heterogeneity in an area will result in greater species richness. This hypothesis has been deemed false for bats, as their ability to fly would reduce opportunities for habitat specialization. If so, we would expect no significant relationships between 1) species composition and environmental variables, 2) species richness and environmental heterogeneity, 3) β‐diversity and environmental heterogeneity. We tested these predictions using 31 bat assemblages distributed across Mexico. Using variance partitioning we evaluated the relative contribution of vegetation, climate, elevation, horizontal heterogeneity (a variate including vegetation, climate, and elevational heterogeneity), spatial variation (lat‐long), and vertical hetero geneity (of vegetation strata) to variation in bat species composition and richness. Variation in vegetation explained 92% of the variation in species composition and was correlated with all other variables examined, indicating that bats respond directly to habitat composition and structure. Beta‐diversity and vegetational heterogeneity were significantly correlated. Bat species richness was significantly correlated with vertical, but not horizontal, heterogeneity. Nonetheless, neither horizontal nor vertical heterogeneity were random; both were related to latitude and to elevation. Variation in bat community composition and richness in Mexico were primarily explained by local landscape heterogeneity and environmental factors. Significant relationships between β‐diversity and environmental variation reveal differences in habitat specialization by bats, and explain their high diversity in Mexico. Understanding mechanisms acting along environmental or geographic gradients is as important for understanding spatial variation in community composition as studying mechanisms that operate at local scales. 相似文献
16.
M. Socorro González-Elizondo Jorge A. Tena-Flores Ma. Teresa Alarcón-Herrera Edith Flores-Tavizón Nélida Barajas-Acosta 《Brittonia》2005,57(2):150-154
A new aquatic, arsenic-tolerant species ofEleocharis (Cyperaceae) endemic to Chihuahua, Mexico, is described and illustrated. It belongs toEleocharis sect.Eleogenus seriesMaculosae. A key for the species ofEleocharis sect.Eleogenus from Mexico is included.
Resumen Sc describe e ilustra una nueva especie deEleocharis (Cyperaceae) acuática, tolerante a altas concentraciones de arsénico, y endémica de Chihuahua, México. Forma parte de la secciónEleogenus serieMaculosae. Se incluye una clave para las especies deEleocharis sect.Eleogenus de México.相似文献
17.
Gone to Texas: phylogeography of two Trachymyrmex (Hymenoptera: Formicidae) species along the southeastern coastal plain of North America
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Jon N. Seal Larrimy Brown Cynthia Ontiveros Jeffrey Thiebaud Ulrich G. Mueller 《Biological journal of the Linnean Society. Linnean Society of London》2015,114(3):689-698
Ants are widely recognized as ecologically important members of many low‐ to mid‐latitude ecosystems. Surprisingly, there is very little phylogeographical information on ants at regional scales. We examine here the phylogeography of two partially sympatric species of Trachymyrmex (Trachymyrmex septentrionalis and Trachymyrmex turrifex) ants in southeastern North America. We test the hypothesis that all Trachymyrmex species found in the USA expanded into North America from refugial populations located in northern Mexico as the post‐Pleistocene climate warmed. Phylogeographical theory predicts that these northward‐expanding species should exhibit higher genetic diversity in regions closer to Mexico and less diversity in more northern regions. We also examine, in the widely distributed T. septentrionalis, the hypothesis of vicariance that occurred at the formation of the Mississippi Embayment. Phylogeographical patterns indicate that T. septentrionalis has an eastern origin because diversity was highest east of the Mississippi, whereas T. turrifex probably has a Mexican origin because it lacked mitochondrial DNA (mtDNA) variation throughout its range and is currently absent from eastern North America. Both species are characterized by reduced haplotypic variation in the western coastal plain of the Gulf of Mexico (Texas and Louisiana), which may indicate recent expansion and/or bottlenecks associated with increased aridity and drought in these western regions. © 2015 The Linnean Society of London, Biological Journal of the Linnean Society, 2015, 114 , 689–698. 相似文献
18.
RAPD variation within and among natural populations of outcrossing buffalograss [Buchloë dactyloides (Nutt.) Engelm.] 总被引:3,自引:0,他引:3
D. R. Huff R. Peakall P. E. Smouse 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1993,86(8):927-934
RAPD markers provide a powerful tool for the investigation of genetic variation in natural and domesticated populations. Recent studies of strain/cultivar identification have shown extensive RAPD divergence among, but little variation within, inbred species or cultivars. In contrast, little is known about the pattern and extent of RAPD variation in heterogeneous, outcrossing species. We describe the population genetic variation of RAPD markers in natural, diploid sources of dioecious buffalograss [Buchloë dactyloides (Nutt.) Engelm.]. Buffalograss is native to the semi-arid regions of the Great Plains of North America, where it is important for rangeland forage, soil conservation, and as turfgrass. Most sources of buffalograss germplasm are polyploid; diploid populations are previously known only from semi-arid Central Mexico. This is the first report of diploids from humid Gulf Coastal Texas. These two diploid sources represent divergent adaptive ecotypes. Seven 10-mer primers produced 98 polymorphic banding sites. Based on the presence/ absence of bands, a genetic distance matrix was calculated. The new Analysis of Molecular Variance (AMOVA) technique was used to apportion the variation among individuals within populations, among populations within adaptive regions, and among regions. There was considerable variation within each of the four populations, and every individual was genetically distinct. Even so, genetic divergence was found among local populations. Within-population variation was larger and among-population variation smaller in Mexico than in Texas. The largest observed genetic differences were those between the two regional ecotypes. These patterns of genetic variation were very different from those reported for inbred species and provide important baseline data for cultivar identification and continuing studies of the evolution of polyploid races in this species. 相似文献
19.
Data are presented on the type-material representing the species described by Linnaeus in his genera Sphex, Chrysis, Vespa, Apis and Mutilla , The names here considered total 158; six are currently applied in the Hymenoptera Parasitica. Of the balance of 147, three are emendations and five are unavailable homonyms or names proposed in the synonymy of other species. Fifteen Linnaean names are here placed as synonyms. One name is attributed to an author other than Linnaeus, and live names remain species incertae sedis. The remainder, 118, are applied as valid names in die Hymenoptera Aculeata. Holotype specimens in London, Uppsala or Stockholm represent 60 names; 55 names are based on lectotype specimens of which 49 are here designated, two by other authors. One name is represented by a neotype specimen in Lund, and one by a lectotype figure. One non-aculeate species is based on syntypes. Specimens appear to be lost with respect to 25 names; three specimens in Uppsala may be the holotypes of a further three species.
Eight new combinations are made, and twelve new synonyms established; three further new combinations and three further new synonymies are suggested. A systematically arranged summary of species treated and of nomenclatural changes made is given. Nomenclatural changes affecting non-Linnaean names are included where relevant; lectotypes are designated for two non-Linnaean species. 相似文献
Eight new combinations are made, and twelve new synonyms established; three further new combinations and three further new synonymies are suggested. A systematically arranged summary of species treated and of nomenclatural changes made is given. Nomenclatural changes affecting non-Linnaean names are included where relevant; lectotypes are designated for two non-Linnaean species. 相似文献
20.
This paper presents the results of a survey on the ethnobotany of the wild Mexican Cucurbitaceae. The sources of information
were fieldwork in different regions of Mexico, as well as herbarium specimens and bibliographic references. A total of 34
wild species (26.5% of the 128 wild mexican species) of Cucurbitaceae are reported as used in 24 of the 32 states of Mexico.
All of the species are called by one or more local names, and 23 are known by names in native languages. The uses comprise
12 categories, including human medicine (18), food (13), soap substitute (12), fodder (4), toy (3), drink (2), ornate (2),
insecticide (1), animal medicine (1), handicrafts (2), container (1), and ceremonial (1), and some uses date back to pre-Hispanic
and colonial times.
Etnobotánica de Especies Mexicanas Silvestres de la Familia Cucurbitaceae
Resumen Este artículo presenta los resultados de una investigatión etnobotánica de las especies mexicanas silvestres de la familia Cucurbitaceae. Las fuentes de informatión fueron el trabajo de campo en diferentes regiones de México, así como también ejemplares de herbario y referencias bibliográficas. Un total de 34 especies silvestres (26.5% de las 128 especies silvestres mexicanas) de Cucurbitaceae son reportadas como útiles en 24 de los 32 estados de México. Todas las especies son conocidas por uno o más nombres locales y 23 de ellas reciben nombres en lenguas nativas. Los usos registrados abarcan un total de doce categorías, incluyendo medicina humana (18), alimento (13), substituto de jabón (12), forraje (4), juguete (3), bebidas (2), ornato (2), insecticidas (1), medicina animal (1), artesanías (2), contenedores (1) y ceremonial (1), y algunos de los usos parecen remontarse a las épocas pre-Hispánica y colonial.相似文献