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1.
Tigridia amatlanensis is described and illustrated as a new species from Mexico. It is recognized by its nodding flowers and its inner and outer tepals cirrhous and markedly dimorphic in length. It is most closely related toT. hallbergii subsp.hallbergii andT. meleagris. Other morphologically similar species areT. catarinensis andT. molseediana.  相似文献   

2.
Sicyos mcvaughii, a new species from Oaxaca, is described and illustrated. It is similar to Sicyos sertuliferus Cogn., and grows in secondary tropical deciduous forest, between 20 and 630 meters.  相似文献   

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Weight, stature, arm circumference, and the triceps skinfold were measured in 1,410 school children, 6 through 14 years of age, from two urban colonias in the city of Oaxaca de Juarez (n = 479), and from two rural Ladino (n = 467) and two rural Zapotec (n = 464) communities in the Valley of Oaxaca in southern Mexico. Children from rural Ladino communities and urban colonias are significantly taller, heavier, and more muscular than children in rural Zapotec communities. The differences between rural Ladino and urban colonia children favor the former, particularly for weight and stature. These observations thus suggest (1) that children in the rural, indigenous communities in the Valley of Oaxaca are relatively undernourished compared to children in Ladinoized and urban communities, and (2) that rural-to-urban migration does not necessarily result in improved growth status.  相似文献   

6.
Primate conservation requires a better knowledge of the distributions and statuses of populations in both large areas of habitat and in areas for which we currently have no information. We focused on spider monkeys (Ateles geoffroyi) and howler monkeys (Alouatta palliata) in the state of Oaxaca, Mexico. This Mexican state has protected large tracts of forest, and has historical records for both primates, although very little is known about them. To update our knowledge of the distributions of these primates and identify potential areas in which they are present, we modeled their geographic distributions by characterizing their ecological niches using the genetic algorithm for rule-set production (GARP), performed interviews and carried out field surveys. The predicted distributions, surveys and interviews indicate that the distributions of these primates are restricted to northeastern Oaxaca. The results suggest that spider monkeys occupy a wider area and elevational range than howler monkeys. Throughout that range there is a wide variety of suitable habitats for these primates. Most of the sites where monkeys were recorded in the field are not officially protected and there was evidence of hunting and habitat destruction. It is important to improve protection, economic alternatives and environmental education as we move towards an integral solution for the conservation of these species. Validation of the GARP model was done for A. geoffroyi, since we had obtained enough field data for this species; this validation indicated that the predicted distribution of the species was statistically better than expected by chance. Hence, ecological niche modeling is a useful approach when performing an initial assessment to identify distribution patterns, detecting suitable areas for future exploration, and for conservation planning. Our findings provide an improved basis for primate conservation and productive fieldwork in Oaxaca.  相似文献   

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Tapirira chimalapana is a new species of tree common in the rain forests and lower montane forests of the Isthmus of Tehuantepec in the Mexican states of Veracruz and Oaxaca. It is most similar to the AndeanT. guianensis Aubl. subsp.subandina Barfod &; Holm-Niels. but differs from this and all other congeners by having larger petals on pistillate flowers than on staminate flowers and by pubescence features. Details of field characteristics, distribution, ecology, phenology, germination, and local names and uses are included.  相似文献   

9.
Adult stature and the age at menarche among individuals from Zapotec-speaking communities in the Valley of Oaxaca in southern Mexico are considered in a secular perspective. Four sets of observations are utilized: (1) adult stature in males and females from five rural communities; (2) age at menarche in adult women and school girls from a single rural community; (3) earlier studies of adult stature in the Valley of Oaxaca; and (4) estimated stature from long bones excavated in various archaeological sites in the Valley of Oaxaca. There were no significant differences among the five communities for stature; hence, the data were pooled for analysis and comparison. Results of linear regression of stature and stature adjusted for the estimated effects of aging after 30 years of age on year of birth indicate negligible secular changes in either sex. Comparisons with statures from earlier surveys, the earliest dates to 1899, also indicate negligible changes. When adult women are grouped according to age, there are no differences in mean ages at menarche between the older and younger women. Mean age at menarche for the total adult sample is 14.53 ± 0.08 years, which compares favorably with the probit estimate for school girls, 14.70 ± 0.32 years. These results thus suggest virtually no secular change in adult size and maturity of the Zapotec-speaking population in the Valley of Oaxaca over the past 80 years. Differences in stature between contemporary populations and estimated statures from long bones from several archaeological sites in Oaxaca are small, and thus suggests little secular change over the past one to two–thousand years.  相似文献   

10.
In the present study, two new species of Gyrodactylus are described from Profundulus oaxacae, a fish endemic to the Pacific slope of Oaxaca State, Mexico. Fishes were collected within their distribution range in 5 localities in the Atoyac-Verde River. Gyrodactylus montealbani n. sp. and G. zapoteco n. sp. were erected and characterized morphologically (sclerites of the attachment apparatus and the male copulatory organ) and molecularly (sequences of the Internal Transcribed Spacer region of rDNA). The haptoral sclerites of the new species are similar to those of Gyrodactylus iunuri and Gyrodactylus tepari, both recently described from the goodeid fish Goodea atripinnis, from the Mexican States of Jalisco and Querétaro, respectively; and to Gyrodactylus xtachuna described from the poeciliid Poeciliopsis gracilis in Veracruz State, Mexico – nonetheless, these species can all be discriminated based on their marginal hook morphology. Specimens of G. montealbani n. sp. and G. zapoteco n. sp. were sequenced, and were aligned with sequences of 25 other Gyrodactylus spp. Both Maximum likelihood and Bayesian inference analyses indicated that the two new species are members of independent, well-supported lineages – these are the first Gyrodactylus species described from Profundulus oaxacae.  相似文献   

11.
In this article, I highlight the challenges, tensions, and affinities between Latino educational anthropology and diaspora studies. Some of the urgent questions include attention to new Latino destinations, transnationalism, and Latino diversity. It concludes by suggesting future pathways through Latina feminist thought.  相似文献   

12.
This survey investigated the prevalence of ethnomedical syndromes and examined treatments and treatment-seeking in Mayan Guatemalans living in United Nations High Commissioner for Refugee (UNHCR) camps in Chiapas, Mexico. Methods included a rapid ethnographic assessment to refine survey methods and inform the cross-sectional survey, which also examined mental health outcomes; 183 households were approached for interview, representing an estimated 1,546 residents in five refugee camps and 93% of all households. One adult per household (N = 170) was interviewed regarding his or her health; an additional 9 adults in three surveyed households participated and were included in this analysis; of the 179 participants, 95 primary child-care providers also answered a children’s health questionnaire for their children. Results indicated that ethnomedical syndromes were common in this sample, with 59% of adults and 48.4% of children having experienced susto (fright condition) and 34.1% of adults reporting ataques de nervios (nervous attacks); both conditions were significantly associated with symptoms consistent with posttraumatic stress disorder, anxiety and depression and are mental health conditions recognized by the American Psychiatric Association. Combining healthcare provider and indigenous treatments such as physician prescribed medication (65%), medicinal plants (65.7%), and limpias (spiritual cleansings) (40.6%) was reported. Most participants (86%) sought routine medical treatment from UNHCR trained health promoters in their camp. Assessing ethnomedical health is important for informing mental health programs among this population.  相似文献   

13.
A total of 1,302 parasitoids representing 8 species and 4 families were recovered from 9,818 fruit fly host fruits sampled. The most common parasitoid species wasDiachasmimorpha longicaudata (Ashmead). Average percent parasitism ranged between 0.44 and 29.23%. Parasitoid emergence data indicate thatAnastrepha ludens (Loew),A. obliqua (Sein),A. serpentina (Wiedeman),A. striata (Schiner) andToxotrypana curvicauda (Gerstaecker) were subject to parasitism. We provide information on the population fluctuation ofAnastrepha ludens, A. obliqua, A. serpentina, A. distincta (Greene),A. striata, A. fraterculus (Wiedeman),A. chiclayae (Greene),A. montei (Costa Lima),A. leptozona (Hendel) andA. tripunctata (Wulp).Anastrepha ludens andA. obliqua were the most common species, representing 95.3% of all fruit fly species caught in McPhail traps.   相似文献   

14.
The systematics and taxonomy of North Americancyprinid fishes has historically been said tobe in a chaotic state of affairs. Much of theconfusion as to relationships of species restsin the lack of explicit phylogenetic hypothesesof species and reliance upon degree ofdistinctiveness of taxa or their overallsimilarity for generic placement. Some specieshave had more turbulent or variable taxonomichistories than others. The ornate shiner, Cyprinella ornata, is one of those species,having been placed in the genera Notropis,Codoma, and Cyprinella within the last20 years and found in current texts in any ofthese three genera. Most of the confusionregarding placement of this species has beenrelated to lack of explicit phylogenetichypotheses to formulate its classification, butto a certain degree some researchers haveignored phylogenetic studies and preferred torely upon its morphological distinctiveness orreproductive behavioral traits of questionablehomology to place it in a monotypic genus andalign it with the genera Pimephales andOpsopoeodus.I present a phylogenetic analysis based oncomplete Cytochrome b sequences fromornate shiners, other species of Cyprinella, purported relatives, and severalother species of the Shiner Clade to determinethe phylogenetic affinities of this enigmaticspecies. Molecular analysis reveals the ornateshiner to be more closely related to species ofCyprinella than to a Pimephalesplus Opsopoeodus clade as previouslydiscussed in one morphological analysis, or asargued by Page and Johnston (1990), Johnstonand Page (1992) and Page and Ceas (1989) basedon observations of spawning behaviors andhypotheses of homology between crevice-spawningand egg-clumping behaviors. This molecularanalysis is more consistent with earliermorphological phylogenetic hypotheses of Mayden(1989) wherein these two clades are notconsidered to be closely related and the ornateshiner is a member of the genus Cyprinella.  相似文献   

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Conservation of forested riparian ecosystems is of international concern. Relatively little is known of the structure, composition, diversity, and extent of riparian ecosystems in Mexico. We used high- and low-resolution satellite imagery from 2000 to 2006, and ground-based sampling in 2006, to assess the spatial pattern, extent, and woody plant composition of riparian forests across a range of spatial scales for the state of Sonora, Mexico. For all 3rd and higher order streams, river bottomlands with riparian forests occupied a total area of 2,301 km2. Where forested bottomlands remained, on average, 34% of the area had been converted to agriculture while 39% remained forested. We estimated that the total area of riparian forest along the principal streams was 897 km2. Including fencerow trees, the total forested riparian area was 944 km2, or 0.5% of the total land area of Sonora. Ground-based sampling of woody riparian vegetation consisted of 92, 50 m radius circular plots. About 79 woody plant species were noted. The most important tree species, based on cover and frequency, were willow species Salix spp. (primarily S. goodingii and S. bonplandiana), mesquite species Prosopis spp. (primarily P. velutina), and Fremont cottonwood Populus fremontii. Woody riparian taxa at the reach scale showed a trend of increasing diversity from north to south within Sonora. Species richness was greatest in the willow-bald cypress Taxodium distichum var. mexicanum—Mexican cottonwood P. mexicana subsp. dimorphia ecosystem. The non-native tamarisk Tamarix spp. was rare, occurring at just three study reaches. Relatively natural stream flow patterns and fluvial disturbance regimes likely limit its establishment and spread.  相似文献   

17.
We used a well-characterized barley mapping population (BCD 47 × Baronesse) to determine if barley stripe rust (BSR) resistance quantitative trait loci (QTL) mapped in Mexico and the USA were effective against a reported new race in Peru. Essentially the same resistance QTL were detected using data from each of the three environments, indicating that these resistance alleles are effective against the spectrum of naturally occurring races at these sites. In addition to the mapping population, we evaluated a germplasm array consisting of lines with different numbers of mapped BSR resistance alleles. A higher BSR disease severity on CI10587, which has a single qualitative resistance gene, in Peru versus Mexico suggests there are differences in pathogen virulence between the two locations. Confirmation of a new race in Peru will require characterization using a standard set of differentials, an experiment that is underway. The highest levels of resistance in Peru were observed when the qualitative resistance gene was pyramided with quantitative resistance alleles. We also used the mapping population to locate QTL conferring resistance to barley leaf rust and barley powdery mildew. For mildew, we identified resistance QTL under field conditions in Peru that are distinct from the Mla resistance that we mapped using specific isolates under controlled conditions. These results demonstrate the long-term utility of a reference mapping population and a well-characterized germplasm array for locating and validating genes conferring quantitative and qualitative resistance to multiple pathogens.  相似文献   

18.
In central Mexico, the center of origin forLeptinotarsa decemlineata (Say) and its principal host plants,L. decemlineata is associated with a diverse complex of natural enemies. Observations during 2 years in Morelos, Mexico revealed 4 species of asopine pentatomids, 7 species of foliar searching carabids, and 2 coccinellids among the predators ofL. decemlineata. Parasitoids include 3 species of tachinids andEdovum puttleri Grissel, an eulophid egg parasitoid. These natural enemies include several predators that have not previously been reported attackingL. decemlineata. University of Maine Agriculture Experiment Station No. 1553  相似文献   

19.
Agar properties of two potentially commercial important seaweeds from the Gulf of California were studied. Maximum yield in Gracilaria vermiculophylla (45.7%) occurred during the summer months, coinciding with high water temperatures (31°C) whereas minimum yields (11.6%) were obtained during the coldest months of the year when populations of this species diminish in the bay. Gracilariopsis longissima showed two yield peaks, one in spring and another in fall, before the maximum and minimum seawater temperatures. Gel strength in native agar from the two species was low (<22.5 g cm−2) for most of the year. G. vermiculophylla native agar showed a slight increase in gel strength from June to August, which were the hottest months. Maximum value was 85 g cm−1 in August. Maximum gel strength in G. longissima was observed in October (91 g cm−1), and an unusual native agar with no detectable gel strength was observed in March and April samples. Gelling temperatures range from 27.7 to 36.5°C in G. vermiculophyla and from 26.6 to 34.9°C in G. longissima, meanwhile melting points were 73.9 – 53.5°C and 75.5 – 56.6°C, respectively. Sulfate content was high, 6.3–13.9% in G. vermiculophylla and 1.9–11.9% in G. longissima, and on the other hand 3,6 anhydrogalactose content was low 12.1–26.7% and 9.1–23%, respectively compared to other species. Results obtained showed that mean native agar yields of Gracilaria vermiculophylla and Gracilariopsis longissima from the Gulf of California are comparable to other tropical Gracilaria. However, the low gel strength, high sulfate content and low 3,6 anhydrogalactose content observed in the native agar extracted from these species make this an agaroid, thus alternative methods of extraction should be used to evaluate the possibility of commercial utilization of both species.  相似文献   

20.
Yucca linearifolia is described, illustrated, and distinguished from other yucca species. Its distinctive combination of fleshy fruit and narrow, linear, denticulate leaves sets it apart from all other yuccas. Se describe e ilustraYucca linearifolia y se discute su separación de otras especies del géneroYucca. La combinación de caracteres tales como el fruto, carnoso y la hoja linear y denticulada la distingue del resto de las especies del género.  相似文献   

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