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In this study the wood anatomical description of 12 species characteristics from cloud forest in the State of México was carried out. For each species the qualitative and quantitative microscopic characters of wood are described. On the basis of the Runkel relationship, the quality of their fibers is classified to obtain pulp for paper. The morphological characteristics of each species are given, as well as their common names and national distribution. Eight species have growth rings formed by bands of fibers with lumens reduced and thick walls, or compressed radially, in the late wood. The porosity is diffuse; the vessels are small, with less than 100 µm diameter, and numerous. Several species presented vessel elements with scalariform perforation plates Vessel elements and fibers were medium and long. In general the axial parenchyma is scarce and in seven species the rays are heterogeneous type I. These results are similar to those obtained in other regions. According to the relationship of Runkel it was found out that the fibers are of medium to good quality for paper. [ABSTRACT FROM AUTHOR]

In this paper, we document the role and potential of plant resources in the Popoloca community of Zapotitlán Salinas, Puebla, located in the most arid zone of the Tehuacán-Cuicatlán Valley. In total, 298 species belonging to 82 families were found. Ethnobotanical information is included for 288 species belonging to 219 genera and 79 botanical families, whose uses are placed in 19 categories. A total of 164 species are wild plants growing in different natural plant communities and in some of the transformed areas, while 124 can be found exclusively in the homegardens. The families with the highest number of useful plants were Poaceae (35 spp.), Cactaceae (24 spp.), and Asteraceae (23 spp.). Most of the useful plants are herbs (162 spp.), followed by shrubs (86 spp.) and trees (41 spp.). The paper includes information about spatial and seasonal availability of the useful species, as well as data concerning relative importance of the most important ones, such as those used as medicine, food, firewood and fodder. [ABSTRACT FROM AUTHOR]

This paper is part of an ongoing series of taxonomic investigations documenting the richness of conidial fungi occurring on plant debris in the cloud forests of Veracruz, Mexico. In the present paper 18 species are described; 15 of which are new to Mexico, and three were collected for the first time in a cloud forest habitat. [ABSTRACT FROM AUTHOR]

I analyzed information about studies of white-tailed deer (Odocoileus virginianus), mule deer (O. hemionus), red brocket deer (Mazama americana) and brown brocket deer (M. pandora), in Mexico. I compiled 502 papers written between 1850 and early 2001. Only 24% were accomplished during the first 130 years, and 76% were done in the last 20 years. One percent were books, 13% were specific articles on deer, 12% were sections or chapters in books, 16% were articles on other mammals including deer, 7% were articles in popular science magazines, 11% were thesis and 40% were works published in proceedings of meetings. The brocket deers and mule deer were the least studied species. The white-tailed deer was the most studied species with 75% of the total number of research papers. In particular, only five of the 14 subspecies of white-tailed deer were the most studied: O. v. texanus, O. v. couesi, O. v. sinaloae, O. v. mexicanus and O. v. yucatanensis. Based on this analysis, future research and management should consider: 1) Increase the studies on mule and brocket deers. 2) Carry out studies on genetics and distributions to define how many white-tailed deer subspecies exist in Mexico. 3) Approach studies from a landscape perspective incorporating fragmentation and metapopulations. 4) Carry out long-term studies. 5) Link research to specific management problems. 6) Rescue the ethnozoological knowledge of the indigenous people about deer species. 7) Evaluate the role that deer have as structural agents of vegetation in tropical habitats. 8) Search for ways of management for the white-tailed deer subspecies that inhabit the tropical forest. 9) Classify the country in white-tailed deer management regions or provinces. 10) Create a information data bases. Finally, in this paper a complete list of all bibliography references is presented. [ABSTRACT FROM AUTHOR]

This contribution is essentially a complement to the data and concepts exposed in a previous paper, devoted to the topic of diversity and origins of the Mexican phanerogamic flora. A part of the mentioned paper deals with the subject of endemism which, according to evidence and estimations, involves the family level and accounts for ±10% of the genera and ±52% of known species. If an ecologically more natural area (wich expands the territory of Mexico by about 1/3)is taken as reference, these figures rise respectively to ±17% and ±72%. If these figures are compared with existing information for other countries and regions of the world, it can be concluded that the extent of endemism in the flora of Mexico is not as large as that of Australia, Madagascar or South Africa, but surpasses that of Cuba and of the California floristic province and is much larger than those of many other parts of the world. The origin of this significant wealth of endemic organisms must be sought on the one hand in the existence of a fair number of regions that behave as true ecological islands and peninsulas within the territory of Mexico, some of them extending over large portions of the country, and on the other hand, in the events and environmental conditions of the geological past. Particularly, it must be emphasized that during much of the Cenozoic era no terrestrial connection existed with South America and accordingly Mexico bore the form of a peninsula which, much like South Africa, penetrated in form of a wedge toward climatic conditions in sharp contrast with those prevailing on the wider part of the continent. Different types and aspects of endemism in Mexican flora are discussed and it is pointed out that an important proportion of very local and/or rare species can be recognized. The majority of endemics, however, do not belong to this group and in fact many of the most common and characteristic plants of the Mexican landscape belong to taxa of restricted distribution, including a large number of weeds and some cultivars. Gypsophytes stand out among edaphic endemics and this group seems to bear a long evolutionary history. A large additional assemblage of paleoendemics can be distinguished, in part concentrated in areas which acted as refugia during the epochs of changing climates of the Tertiary and the Quaternary. A rough estimation indicates that endemism in the Mexican flora is most accentuated among shrubs' and perennial terrestrial herbs, whereas lianas and aquatic plants show the lowest incidence. Among the larger families, Cactaceae, Rubiaceae and Compositae stand out with about 70% of endemic species, while Orchidaceae and Gramineae only reveal 35% and 25% respectively. A remarkable correlation can be observed between the proportion of endemic genera arid the degree of climatic aridity. At the species level, however, temperate and semi-humid areas are equally privileged in endemics. On the other hand in warm and humid regions endemism is poorly represented. Numbers of localities and regions are indicated, in which a significant concentration of floristic endemism has been detected and in general terms it can be observed that endemic genera are much better represented in the northern half of the country, whereas endemic species are more numerous on the Pacific slopes than on the Atlantic. It is pointed out, however, that in most parts of the country, practically at any point, the flora of terrestrial and not excessively disturbed communities includes a high percentage of endemics. [ABSTRACT FROM AUTHOR]

In this paper we report new localities for Abronia oaxacae and Tantalophis discolor in a pine forest with intense management in San Pedro El Alto locality, municipality Zimatlán, in the state of Oaxaca, southwestern Mexico. These new localities extends the known range of both species. [ABSTRACT FROM AUTHOR]

The Southwest region of the State of Mexico (PSEM as it stands in Spanish) is located in the so called Mexican Transition Mountainous Zone. The forest communities that prevail in this area are pine trees forests (Pinus spp.), oak trees forests (Quercus spp.), mixed ones, mountainous cloud forest and tropical deciduous forest, which are being modified due to the influence of human processes. This research paper establishes a methodology to analyze the changes on the land cover of the PSEM which took place from 1989 to 2009 using a technique of image satellite interpretation (Landsat TM), as well as the use of the maximum authenticity algorithm which leads towards the implementation of soil and vegetation maps whose main purpose is to obtain information on the validity of these study cases. Overlapping those maps, it is possible to come up with a matrix of changes to check annual modifications on the land cover, and based on it the changes rates can be measured. From data obtained through this research, it can be stated that the land cover of this forest has considerably decreased because 19 262 ha disappeared and were taken up by water supplies (105 ha), farming lands (19 113 ha), human settlements (39 ha) and technical and controlled agriculture (5 ha). It can be summed up that this deforestation mainly comes as a result of the practice of agriculture and livestock activities indeed. [ABSTRACT FROM AUTHOR]

Woody flora of cloud forest (BMM) in Tamaulipas has different taxa with respect to other BMM in Mexico. Consequently, wood anatomical characters of its species can also express this variability, related to environment and the linages to which they belong. In this paper, wood anatomy of 12 species growing in of the BMM at "El Cielo" Biosphere reserve in Tamaulipas, Mexico was described. Unlike other Mexican BMM, results showed a positive trend with respect to the presence of conspicuous growth rings. This character seems related to the geographical position of this BMM in Mexico. Other characters such as diffuse porosity, tangential vessels diameter < 100 µm, vessel elements with helical thickenings and length >350 µm, fibers lengths > 900 µm, and scarce axial parenchyma, are common features in the species studied. Some anatomical characters of taxa were compared with related groups at the genus or family level. [ABSTRACT FROM AUTHOR]

Mesquite is one of the most important forest resources in northern Mexico, constituting an important part of the national flora and its great importance to the inhabitants of the arid and semiarid regions. This paper shows a volumen and wood weight table obtained in m³ which can be used in the área of influence. This technique was based on dimensional analysis, measuring the tres readily available, which enables farmers, foresters and institutions, rely on production parametersand volumen of timber (wood) for the rational and sustainable use of natural populations of mesquite, in turn providing protection and conservation of the environment. The evaluation was conducted in Ejido San Antonio de la Sierrecilla, municipality of Mazapil, Zacatecas. The largest diameter was measured on crown and total height in cm, destructive sampling was carried out in 39 trees, and volume and weight of branches were determined. In regression analysis polynomial model was used resulting in timber volumen (m³)=2,341E-6X²-0,0012X+0,1803 and determination of weight (kg)=0,001X2- 0,556X+81,909*D with 95% reliability. [ABSTRACT FROM AUTHOR]

Recent studies have suggested that climatic variations may have implications on ecosystem biogeography. Dendrochronological techniques constitute a useful tool to analyze relationships tree growth-climate. Ring widths usually are standardized before the analysis in order to remove unwanted bias due to individual growth related to stem size and age. This approach produces rings widths indices while retaining climatic signals that are in common among trees into a single chronology. However, in dendroclimatology few papers show their sensitive capacity. As a result its use could be becomes routine practice without considering their implications. The aim of this work was to assess the climate sensitivity responses of three chronologies indexes of Pinus cooperi: Standard (Sd), Residual (Rd), and Arstan. Such series were correlated with historical records of precipitation, temperature and two index El Niño-Southern Oscillation ENSO (Niño3 and MEI).The three chronologies showed similar trends during previous growing months (August to December). Nevertheless, Rd was better associated with current growing months, but showed weaker correlation with ENSO. Comparatively Sd and Ar demonstrated stronger sensibility to large-scale climatic patterns in previous growing months. It is concluded that appropriate selection of dendrochronology index is important, indicating repercussions on climatic scenarios. Neither should be considered substitutes for each other. Combining them with complementary tools would improve the sensitivity capacity of ecological processes in the forest. [ABSTRACT FROM AUTHOR]

Non Timber Forest Products (NTFP) contribute to the food security of forest communities. Around 1000 of those are used in Mexico, but little information is available on local knowledge and women's roles in NTFP management. This paper pursues three objectives: to describe the distribution, light and soil conditions of a NTFP called "poleo" Satureja macrostema (Benth.) Briq.; to document local knowledge on this plant; to analyze gender differences in terms of access, use and trade. Research was conducted in San Miguel Mixtepec, a Zapotec community of the Central Valleys of Oaxaca. Methods include soil and canopy analysis, participant observation, interviews and workshops. Poleo grows under a closed canopy, in slightly acid, organically rich soils. Local knowledge on the plant's reproductive process contributes to its permanence. The plant is used for community rituals, as ornament, food and medicine. Men predominate in the first two uses and women in the remaining ones. Trading activities are female-dominated, mostly by 'widows' (adult women with children and no partner). The plant is informally traded in regional markets at very low prices. However, its barter or sale contributes to diversify local diets and is a good example of women's subsistence activities in the forest communities of Mexico. [ABSTRACT FROM AUTHOR]

Family Aphelinidae is one of the most important in the biological control of insect pests at world level. It includes 34 genera and around 1,300 species, with 12 genera and 184 species in Mexico. Genus Encarsia is the most diverse with 409 species and 94 in Mexico. In this paper, three new species of this genus are described and illustrated: E. antennata sp. n. from Baja California Sur, E. caudata sp. n. from Nuevo Leon, and E. oaxaca sp. n. from Oaxaca and Tamaulipas. [ABSTRACT FROM AUTHOR]

The Protection Area of Flora and Fauna La Primavera (APFFLP) located in western Mexico in the state of Jalisco, is one of 19 protected areas in the state decreed. This area is of great interest to be located in the metropolitan area of the city of Guadalajara and the Transmexican Volcanic Belt. However, it has received little attention and there is not a full inventory of its mammalian fauna. The aim of this paper is to list the species of mammals in the APFFLP, highlight its relevance to other protected areas in the state and the country, and richness within the Transmexican Volcanic Belt. Fieldwork was conducted in two periods, December 2004-December 2006, and October 2010-December 2012. The checklist of mammals was obtained using several techniques such as traps and visual records of the mammals and tracks; we used mist nets for the collection of bats. 59 species were recorded, which are covered in eigth orders, 19 families and 48 genera. The order Chiroptera was the most abundant (27), followed by Rodentia (14) and Carnivora (11). The distribution of species shows that 23 are shared with North and South America; 17 with North America; nine with South America and 10 are endemic to Mexico and Meso America. Three species are considered at risk by Mexican regulations: Cratogeomys fumosus, Leptonycteris yerbabuenae and Choeronycteris mexicana as threatened. In conclusion, APFFLP is important for harboring more species and endemic species than other areas considered relevant in the country, besides being an important area of mammal species richness in the Transmexican Volcanic Belt. [ABSTRACT FROM AUTHOR]

In this paper, three equations were generated to estimate the normal diameter, height and total volume from stump diameter for Quercus laurina stands in Ixtlan de Juarez, Oaxaca, with a sample of 54 trees. Linear and nonlinear models were adjusted to the database to obtain the most reliable equation to the functional relationship: (a) normal diameter - stump diameter, (b) total height - stump diameter and (c) total volume-stump diameter. The criteria for defining the adjustment in all three cases was based on: normal and adjusted coefficient of determination, mean square error, P-value, coefficient of variation, and sum and dispersion of residuals against predicted values. The model with the highest goodness of fit for the estimated normal diameter based on the diameter of the stump was the simple linear regression model, and in the other two cases, it was the potential model. With these equations, it is possible to accurately estimate the dependent variables values and evaluate different scenarios in areas affected by natural or anthropogenic phenomena. [ABSTRACT FROM AUTHOR]

This paper seeks to show the deforestation rate in Mexico based on land use and vegetation changes data from 1976 to 2007 using the official data published by INEGI. The results of the National Forest Inventory for 2000 were added to make a cut and the process was analyzed in two stages from 1976 to 2000 and from 2000 to 2007. Moreover, a polygon level analysis was carried out over the forest with secondary vegetation to know if they are coming from a recovery process or from a degradation process. The results show that the change rates are lower in the 2000-2007 than the 1976-2000 periods, but the annual loss of forest are around the 500 000 ha. For the complete period it was found a forest annual loss of 534 707 ha. The deforestation official data are sub valued since 2006 because they discount the 100% of secondary vegetation, when the real amount of recovery process is over 10% to 13%. The deforestation official data were recalculated from 2006 on, and the new results match with the amount of 500 000 ha per year. The principal use for the deforested areas is still the rainfed agriculture. [ABSTRACT FROM AUTHOR]

The present paper reports new distribution records of Triatoma gerstaeckeri (Stål) in the municipalities of China, General Bravo, Santiago and Villaldama of the state of Nuevo Leon; whereas Triatoma rubida (Uhler) is reported for the first time in the municipality of Ocampo of the state of Coahuila, México. [ABSTRACT FROM AUTHOR]

Chapultepec Forest is the largest and most visited urban green area (UGA) of Mexico City and for these reasons, the protection and conservation of this place is a relevant issue to maintain the generation of the environmental services and benefits that it provides. Despite the importance of this area, there is a lack of information about the horizontal structure and indicators of the tree stands located in this place, as well as for the rest of the UGA of the city and the country, although some floristic or sanitary conditions studies had been done in some of them. The aim of this paper was to determine the dendrological and dasometric characteristics of the stands at the 2nd section of Chapultepec Forest, according with the information obtained from a total tree inventory, complemented with 111 sampling sites of 500 m². The estimated mean of trees per site was 295/ha, the mean crown cover value was 27,19 m² and the canopy cover in the area exceeds 80% of the total surface. The mean basal area was 0,10 m² and the stems occupied 0,32% of the total surface. This data will provide basic indicators for the 2nd section tree stands and a reference for future research projects and characterization of UGA in the city. In addition, the information is basic to sustain the management that requires the urban forest of Mexico City. [ABSTRACT FROM AUTHOR]

This paper describes the birds' structure and composition of associated sites to tropical forest in the Central Depression of Chiapas, Mexico, through 2003 to 2004. I recorded 364 species considering scientific literature, museum collections and field work. Families with highest species richness were Tyrannidae, Parulidae, Icteridae and Trochilidae. Resident birds represented 68% of the total and the 32% remaining were migratory. Thirty four percent of bird species were rare, 11% common and 3% abundant. Highest species richness was found for the tropical deciduous forest (226), followed by the secondary forest (163) and the tropical semideciduous forest (122). From all birds, 136 were additional records in the region and, 56 were for the Sumidero Canyon National Park. The species richness recorded included 45% of the avifauna of Chiapas, indicating the relevance of this region and the urgent need to establish conservation and protection management strategies. The magnitude of species increment and lack of information in this region suggest that regional and local inventories are necessaries to improve the knowledge about species distribution. [ABSTRACT FROM AUTHOR]

Migration counts of raptors have been used as a valid technique to assess population levels. Counts from Veracruz, Mexico, have the potential of generating valuable information for regional- to continental-scale populations of some species and to provide coverage for others that are not monitored elsewhere. This paper evaluates the use of Veracruz migration counts to monitor populations, documents the adjustments made to a currently existing method to analyze migration count data and fit it to the specific properties of our dataset, and presents estimates of population change over a decade. We used long-term, effort-adjusted migration count data to generate annual indexes of abundance. The series of annual indexes is fitted to a polynomial regression to produce an estimate of the annual rate of change. The use of this methodology with Veracruz data shows its usefulness to datasets of many species, as well as limitations to datasets from species with high interannual variation in migration counts, and those recorded rarely. In seven species, the authors found significant population change. Six of them, Swallow-tailed Kite, Mississippi Kite, Cooper's Hawk, Swainson's Hawk, Zonetailed Hawk, and Peregrine Falcon show increases at an annual rate between 1.9-15.7% per year-1 in the period 1995-2005. One species, the Northern Harrier, is decreasing at a rate of -8.4% year-1 during the same period. Trends reported here reveal population increases in most cases, and concur with the pattern found in migration counts from surveys such as the Breeding Bird Survey and the Christmas Bird Count. [ABSTRACT FROM AUTHOR]

This paper describes a user-friendly computer application developed for forest management planning in El Salto, Durango (Mexico). The computer program BWINPro7 version El Salto allows for forest growth and predicts future stand development. It represents an easy tool that can be used by forest managers and owners of forest lands in the decision-making process. The program incorporates individual tree growth models developed for most pine and oak species during recent years in mixed and uneven-aged forests in the north-eastern region of Mexico. Specifically, the models that were incorporated into the program BWINPro7 are: (1) models to estimate crown width and the height to the live crown base, (2) individual tree basal area and height growth models, and (3) a model to predict individual tree mortality. In addition, the simulator can be used in permanent sample plots to describe stand spatial structure, and to prescribe thinning and timber harvest at industrial scale. [ABSTRACT FROM AUTHOR]

Prickly pear, Opuntia ficus-indica (L.) Miller, is cultivated for many purposes around the world. In Mexico, people consume young pads as vegetables and call them "nopalitos". The production of nopalitos occurs mainly around Mexico City where cochineal insects (Dactylopius spp.) are one of the most important pests. Farmers partly control Dactylopius using insecticides, but biological control could offer a tool for the Integrated Pest Management. In this paper the cochineal insects and their natural enemies were studied in Tlalnepantla, Morelos, one of the most important regions for nopalitos production in Mexico. In order to determine Dactylopius species, 30 samples sites were selected in this region. Additionally natural enemies were collected every other week during one year period in five different zones. Dactylopius opuntiae (Cockerell) was the only cochineal species found in Tlalnepantla. The natural enemies, in order of abundance, were Leucopis bellula, Sympherobius barberi, Laetilia coccidivora, Hyperaspis trifurcata, Salpingogaster cochenillivorus, Sympherobius angustus, and Chilocorus cacti. We also included some lab and field biology descriptions of these predators. Diverse factors of crop management appeared to affect D. opuntiae population and their natural enemies. [ABSTRACT FROM AUTHOR]

The Myrtaceae family in Mexico is represented by twelve genera widely distributed in temperate, tropical and semiarid regions. The family has economic importance due mainly to the extraction of wood (from Eucalyptus spp.), of fruit for human use (Psidium spp.) and to the practice of apiculture (in Eugenia spp.), among other uses. Several genera representing the family have been recorded in Quintana Roo, among which Eugenia, with several species, is well represented in the tropical rainforest. Wood of this genus has important local uses: poles and pillars used in the construction of rural houses, it has also been used to build railroad (sleepers). Valuable melifer species have also been found. Its wood structure has been poorly studied; therefore this paper describes the anatomy of Eugenia capuli (Schlecht. & Cham.) Berg. and of Eugenia mayana Standley, wich were collected in the common land (ejido) Cafetal Limones, Quintana Roo. The anatomical descriptions, have produced esthetic, macroscopic and microscopic studies using the three typical cuts and dissociated material. A statistical analysis was done using the measurable characters which were determined based on the value of the mean. Botanical data was included in each description. In both species, the wood is light brown, with diffuse-porous and the vessels have simple perforation plates; the axial parenchyma comes in stripes and it is diffused; rays are heterogeneous type I, II, III and libriform fibres. E. mayana is different from E. capuli in that it has axial parenchyma vasicentric, triseriate rays and its fibres have gums. [ABSTRACT FROM AUTHOR]

In this research paper, information is presented on the dasometric features of standing volume, diameter, top height, tree density, diameter distributions, tree and stand productivity, aboveground biomass, carbon in aboveground biomass and the tree biological diversity of temperate forests of the state of Nuevo Leon, Mexico. This information was derived from 63 inventoried sites within the framework of the forest inventory of 2004-2006. It is concluded that temperate forests are in juvenile state with diameter distributions skewed to the right, with low tree density, low densities of standing volume, biomass and carbon stocks. Tree productivity is also small since it does not surpass on the average 0,36 cm y-1. Tree diversity at the site scale is also small since less than four species are found on the average on these sites. There was statistical evidence that productivity is related to tree diversity and structural diversity in a positive and linear manner. Therefore, there is a great potential to sustainably manage these forests for a wide range of goods and services. It is recommended a light management for goods for 15 years and to carry on the appropriate silvicultural practices to enhance tree diversity as well as structural diversity to increase productivity. [ABSTRACT FROM AUTHOR]

As part of a series of papers dealing with the diversity of anamorphic saprophytic fungi in cloud forest remnants from the Veracruz state, an account of 25 species are described and illustrated. All of them but Helminthosporium solani are new records for the Mexican mycobiota. The species Dictyochaeta tumidospora, Fusariella intermedia, Hyphodiscosia queenslandica and Dictyosporium digitatum had not been recorded since their original description. For all taxa, data about their geographical distribution and substrates are included. [ABSTRACT FROM AUTHOR]

Scientific papers published in Mexican and Latin American journals are usually assigned very low (or even null) value in the research evaluation systems that are currently prevalent in this region. Consequently, our scientists are publishing their most relevant research elsewhere, mainly in journals that are indexed in ISI's Citation Index (CI) and have a high Impact Factor (IF) because these journals are the most highly valued by our evaluators. Latin American journals literally are being deprived of the best contributions from the region, making it even more difficult to acquire the international visibility needed for our journals to become more attractive to our researchers and evaluators. If this cycle continues, our journals will be condemned to a secondary role in the advancement of science and may even disappear. Several scientists have exposed the main problems and limitations of ISI's CI and the IF as indicators of 'good science' and I review these here. I then briefly describe recently developed alternatives that should at least complement these indicators or possibly replace them in the evaluation of research. Finally, I reflect on current practices of research evaluation and propose some measures to break the vicious cycle in which our journals are trapped. My main objective is to contribute to the debate on the indicators employed in our evaluation systems and to stimulate the discussion of the far reaching consequences that the use of these indicators is having on the development of science in Latin America and on the future of our journals. [ABSTRACT FROM AUTHOR]

In this paper, the distribution in Mexico of the ant genus Thaumatomyrmex is analyzed. The Los Tuxtlas region in the state of Veracruz represents the most northern locality for this rare Neotropical genus. Body measurements and photographs of the two specimens collected are provided; the status of the species remains unclear due to the lack of definition on the species diagnostic characters. The rarity of the genus in Mexico is discussed. [ABSTRACT FROM AUTHOR]

Current knowledge about savanna vegetation in Mexico is still incomplete, and it is dominated by an ongoing debate over their natural versus anthropogenic origin. In this paper we provide a detailed structural and floristic description of the savannas of the Nizanda region (Oaxaca, S Mexico). Vegetation was sampled in 20 sites of 15 m² each (totaling 300 m²). A total of 135 morphospecies were encountered, 86 of which could be determined to species level; they were distributed in 29 families and 68 genera. Leguminosae, poaceae and asteraceae were the families with the largest taxonomic richness. Total community cover was 200.7 m², of which 69% was accounted for by grasses and sedges. Despite a clear dominance of Trachypogon spicatus (berger-parker index = 0.82), this community had a relatively large diversity (log[sub 2] shannon = 3.64). Life form spectrum showed a dominance of chamaephytes and hemicryptophytes, indicating a harsh environment. Notwithstanding the widespread occurrence of secondary vegetation and ruderal species in the region, the virtual lack of exotic species in these savannas, together with the presence of some endemics and the identity of the dominant species, strongly support the primary nature of this plant community. [ABSTRACT FROM AUTHOR]

This paper analyzed some socio-economic conditions of forest-dependent, non-forest dependent, and policy-sensitive municipalities in the slate of Durango, Mexico. Knowledge of the socioeconomic relationships among variables that determine the main characteristics of a geographic area is important for planners and decision makers in both public and private sectors. For example, assigning monetary resources for socio-economic development or business expansion requires recognition of the territory boundaries in which the projects are embedded. The study used 51 variables to assess the socio-economic conditions, including poverty and migration indexes, and its influence on current forest conditions. Durango's forests are characterized by pine, oak, and other conifer associations. Yearly, the forest production hits 1,8 million m³r and generates around USD $120 million. While this figures position the state as the first forest producer, it ranks seventh among the Mexican states with the highest rate of illegal immigration, primarily to the USA, and sixteenth with the highest poverty index. The study recommends diversify the use of natural resources and prioritize those policy-sensitive Counties when planning and assigning monetary resources. [ABSTRACT FROM AUTHOR]

Manfreda galvaniae, a new species from the Barranca de Malinaltenango, mpio. Ixtapan de la Sal, State of Mexico, is described and illustrated. It belongs to the Manfreda guttata (Jacobi et Bouché) Rose group, and is similar to M. pringlei Rose and M. fusca Ravenna. Likewise, the paper presents comments about the taxonomic status of M. malinaltenangensis Matuda, sympatric with M. galvaniae. [ABSTRACT FROM AUTHOR]

Taking into account the methodological advancements of the last eight years, the updating of the list to subspecific level of the land native mammals of México (Class Mammalia) is been proposed, including nomenclatural changes that have taken place after 1996. The taxonomic changes, which are included, correspond to suggestion of new classification system, one above the specific level and another for the Order Chiroptera; description of new species; changes of taxonomic status of subgenera, genera, subfamilies, and families; sequence of the different orders into the classification system; separation of the components at generic and specific levels, revalidation of the species and subspecies names; incorporation of the names of species and subspecies into the synonym of others; and, correction of the nomenclature of others. The taxonomic categories mentioned in this paper belong to 12 orders, 34 families, 165 genera (13 are endemics), and 475 species (169 are endemics), 204 are monotypic and, 271 are polytypic species with 951 subspecies, 26 species exclusive to islands The information presented herein correspond only to the land native mammals of México, but the mention of two aquatic genus (Enhydra and Lontra) is made, and are excluded the components of the orders Cetacea, Pinnipedia, and Sirenia. [ABSTRACT FROM AUTHOR]

Several growth and increment in diameter, height and volume equations were fitted and validated for the pine species Pinus cooperi, P. durangensis, P. engelmannii, P. leiophylla and P. herrerae which naturally distribute in the region of El Salto, Durango, Mexico. The results showed that by using the Chapman-Richards equation the first pine species has the highest growth and increment estimated by two different approaches. This paper points out the need to establish permanent sampling plots to calibrate these technologies to be used in growth and yield modeling at the whole stand, size class or individual tree models. [ABSTRACT FROM AUTHOR]

Our knowledge concerning the systematics of Bursera is still very imperfect. In this paper we present an annotated list of 82 Mexican species of this genus that merit at least a provisional recognition, indicating for every species its known geographical distribution on the state level. On the basis of this information a map and a table are presented showing the diversity of Bursera in the 32 Mexican administrative divisions. Forty eight species are reported for Guerrero, 37 for Michoacán and Oaxaca, and 28 for Jalisco and Puebla. Tlaxcala has no recorded species, while Nuevo León, Tabasco and Quintana Roo shelter only one species each. A list of 33 Mexican species of Bursera with restricted distribution (40.3% of the total) is also presented, 10 being reported only from the type locality and its surroundings, 10 additional ones known only from one state, and 13 extending their areas into two contiguous states. On the basis of these data six areas are defined and mapped, in which endemic species of the genus are known to concentrate. [ABSTRACT FROM AUTHOR]

This paper reports the richness of bird species in the northeastern region of the Sierra Nevada mountains, Mexico, from August to November 2001 and from February to June 2002. A total of 104 species representing 34 families and 11 orders were recorded, of wish 88 were resident and 16 were migrants. Forty percent of the species were abundant, 22% scarce, and 38% rare. The richest families were Parulidae (13 species), Emberizidae (11) and Turdidae (9). Sixty-five species were considered core and 39 vagrant. This study adds 43 species to the inventory for this region of the state of Mexico. [ABSTRACT FROM AUTHOR]

The Sontecomapan mangrove is located at Los Tuxtlas Biosphere Reserve, in the southern of Veracruz, Mexico. Currently, this area is listed in the Ramsar index with number 1342. Its biological, cultural and economical values are recognized. This ecosystem represents habitat, refuge, nesting area and nursery for numerous species. A distinctive characteristic of this mangrove is the high forest structure compared with other mangrove forests in Veracruz and as well as the high number of plants associated to this ecosystem, mainly epiphytes and orchids, many of them endangered. At the moment, their cultural value is underestimated, although the area of the swamp of Sontecomapan had relevance from the prehispanic time mainly by the Olmecan culture. Its economic value is as a food source and revenue for many people. However, several problems are affecting its conservation, such as the advance of human settlement on swamp land, illegal hunting, among others. This swamp constitutes a natural area protected administered by the Universidad Veracruzana. This paper described the initial strategy of preservation of this ecosystem, the formulation of a Management Plan. Investigation, education and conservation are the main objectives. [ABSTRACT FROM AUTHOR]

Buteogallus anthracinus is a tipically resident specie that create its nesting at the mangrove forest of Sontecomapan. This paper describes the nesting of B. anthracinus, evaluating size, composition vegetal of the nests and the specie host tree. In 2002 and 2003 by means of routes in boat and with special emphasis to sound emmission to six nests were located on mature trees were. It was found thah Rhizophora mangle, Laguncularia racemosa and Aviccenia germinans are used by B. anthracinus as host trees. The nests are oval in shape with an average 38,5 cm of in diameter, 69,83 cm of external diameter and 52,5 cm in height. The center of the nest is constructed mainly with-leaves of Avicennia germinans and the rest of Rhizophora mangle. It is discusses that the population of B. anthracinus can be dependent on the nest sites in this mangrove. [ABSTRACT FROM AUTHOR]

Based on the revision of herbarium specimens and palynological evidence, a taxonomic study of the Mexican species of the genus Sicydium is proposed. A total of four species are recognized for Mexico: Sicydium davilae, endemic to the state of Chiapas, S. schiedeanum and S. tamnifolium, widely distributed in tropical America, and S. tuerckheimii, distributed from southern Mexico to Central America. The paper presents comments about the variation found in the most relevant morphological and palynological characters. The taxonomic part includes an identification key to the species, as well as descriptions, synonymy, habitat and geographic distribution data, and illustrations. [ABSTRACT FROM AUTHOR]

The Mexican Gray Wolf (Canis lupus baileyi) is one of the most distinctive groups of wild canids. It has been erradicated from most of its original range and there is no solid evidence of wild populations. All known individuals of this species are kept in zoos or special enclosures. Recently a great deal of efforts have been done in oder to reintroduce this subespecies to its natural habitat. Studies on this species are focused on the behavior and social structure, but there are few on the reproductive physiology. In this paper we analyze progesterone (P4), testosterone (T) and estradiol (E2) concentrations in feces of a pair of Mexican grey wolves during the Winter and Spring. Steroids were quantified by enzime immunoassay and evaluated using a micro titer plate. We tested the use of hormone levels to determine gender of the animals and found T to be useful. In the male, P4 levels had a cyclic pattern with peaks in January and February that coincided with cyclic variation in T. E2 did not show significant changes. In the female, P4 showed a cyclic pattern with fluctuations from January to April, T followed the same pattern, and E2 peaked in January, February, and April. The peak of February ended with a rise in P4. These results suggest that concentrations of sexual steroid hormones are in general high during the reproductive period. [ABSTRACT FROM AUTHOR]

Behria tenuiflora Greene is an endemic taxon of the southern part of the Baja California peninsula, Mexico. The wild populations are distributed in an altitudinal range from the top of the mountains at 2200 m to practically the sea level. In this paper we neotypify B. tenuiflora since the type specimen is lost. A detailed description and an illustration of the plant are included. [ABSTRACT FROM AUTHOR]

In this paper a catalog of type specimens of vascular plants held in the herbarium of the Instituto de Ecología, A.C., located in Pátzcuaro, Michoacán, Mexico (IEB), is provided. The collection includes 340 specimens designed as primary types (85 holotypes, 247 isotypes, 2 neotypes and 6 isoneotypes), which represent the nomenclatural reference for 286 taxa. [ABSTRACT FROM AUTHOR]

Beta diversity, or species turnover, is a poorly understood component of species richness. In the case of Mexico, empirical evidence shows that beta diversity is a more important determinant of regional diversity than the alpha or local component. Therefore, the unusual species richness of Mexico is more a consequence of a strong geographic species turnover rather than a particularly high local diversity. The hypothesis of Mexico as a beta-diverse country is based not only on indirect inferences but on data that have been accumulated in the scientific literature in the last few years. In this paper, we review that information and present new analyses that explore the contribution of species turnover to the building of the megadiversity of Mexican mammals. In an analysis using latitudinal bands, we found that the pattern of variation of beta diversity along a latitudinal gradient is similar for volant and non-volant mammals. However the patterns of diversity of terrestrial mammals are much more associated to beta diversity. In exploring beta diversity within biogeographic provinces defined with the distribution of mammals, we found that the relative contribution of alpha and beta diversity to the regional species richness varies geographically and is correlated with different environmental variables. We also present data showing the effect of heterogeneity on alpha and beta diversity, and show a direct relationship between beta diversity and the complementarity among sites in selecting priority areas for the conservation of biological diversity. [ABSTRACT FROM AUTHOR]

A dichotomous key of 21 species of Pluteus Fr. recorded from Nueva Galicia, Mexico, is presented. This paper is part of the results obtained from the study of this genus in the region. Short comments of the 21 species and examined materials are included. [ABSTRACT FROM AUTHOR]

In this paper, Sectiliclava placidae sp. nov. is described, and the fore wing and antenna are illustrated from specimens collected with entomological net in Ciudad Victoria, Tamaulipas, México. Information about distribution is included. A key to species of the genus is presented. [ABSTRACT FROM AUTHOR]

This paper gives accounts for some ancient insects, that were obtained in relation to funerarius deposits inside the "La Chagüera" cave, localized near Ticuman, Morelos state, Mexico, during the archaeological and archaeobotanical studies under Ticuman 94 Proyect. Fragments of three orders of insects were found: Coleoptera, Diptera and Lepidoptera, and also some fragments of Diplopoda, Polydesmida Rhachodesmidae. The following taxa were determined: the Coleoptera family Scarabaeidae, with the genera Dichotomius, Ontophagus, which are attracted by carrion and Copris, which prefers excreta; the family Trogidae, represented by the genus Omorgus, which has affinity for carrion. The family Melolonthidae with the phytophagous genus Cotinis and Hologymnetis; the family Dermestidae, represented by Dermestes, with preferences for dry organic matter. Fragments of Tenebrionidae, belonging to the genus Eleodes and Asidinae, as well as one prothorax of Elateridae and some elytra of Lampyridae or Meloidae were found. The order Diptera was represented by the family Calliphoridae with the genus Phormia that visits carrion; the family Stratiomyidae, represented by the genus Hermetia that frequent corpses; the subfamily Cuterebrinae with the genera Cuterebra and Hypoderma which are hypodermical parasites in vertebrate animals. The order Lepidoptera was determined only to the family Tinaeidae. It is difficult to explain the presence of Cotinis and Hologymnetis elytra, because they are phytofagous insects and cannot visit the dark areas inside the cave, but possibly they correspond to cultural activities of the ancient population, being very difficult to prove. The presence of Cuterebrinae can be explained because they parasitized some vertebrates that visited the cave. This is the first time the relationship between insects and funeral deposites with an age of 200 B.C.-200 A.D. inside a cave, are registered for Mexico. [ABSTRACT FROM AUTHOR]

The municipio of Culiacán has an area of 4 758.9 km² and is located in the central portion of the state of Sinaloa. Its topography is relatively flat, with a large percentage of its surface occurring below 300 m of altitude and only few places surpass 500 m above sea level. The main vegetation type is the thorn forest; however, the mangrove forest, the tropical deciduous forest, the tropical subdeciduous forest, the Quercus forest, and the Pinus and Quercus forest are also present although in less proportion. An inventory of the vascular flora recorded 1 445 native species and subspecific taxa, in 623 genera and 145 families. 162 endemic taxa to western (W) and northwestern (NW) regions of Mexico are present in the municipio of Culiacán, two of them being restricted to its political borders. In this paper, a checklist of the endemic taxa to W and NW Mexico occurring in the municipio is presented; their distribution patterns at state level in the region are also discussed. [ABSTRACT FROM AUTHOR]

In this paper a taxonomic classification for the chayote, Sechium edule (Jacq.) Swartz, that includes two subspecies: S. edule ssp. edule and S. edule ssp. sylvestre, is proposed. Additionally, wild populations of the species are documented for the first time for the states of Querétaro and Puebla, México, and distributional data for similar populations so far recorded in the country are also provided. [ABSTRACT FROM AUTHOR]

The object of this paper is to analyze the Mexican coastal flora of the Gulf and Caribbean. Floristic and vegetation analysis of 44 beach sites comprising the Atlantic littoral of Mexico, revision of herbarium specimens (MEXU and XAL) and bibliography was used to obtain information. It was used to build a data base resulting in 655 species and 91 families. Species number per family and per site was obtained. Growth forms, species distribution in microhabitats, presence of species with different distribution or habitat preference (i.e. coastal, belonging to other vegetation types or secondary) are analyzed. Species frequency distribution along the Gulf sites is also discussed. Endemics and new records for Mexico are given. A synthesis of the coastal flora, its composition and problematics are analyzed, within the framework of an ecological point of view. [ABSTRACT FROM AUTHOR]

The state of Nayarit occupies a strategic position in Mexico; it encompasses the vertex of three important mountain ranges (Eje Volcánico Transversal, Sierra Madre Occidental and Sierra Madre del Sur); this largely determines its high floristic diversity. In the state, Asteraceae is the most diverse family of flowering plants, with 122 genera and 447 species. This paper includes an updated list of species of Asteraceae found in Nayarit and this diversity is compared to that found in the neighbouring states. A list of the endemic species to Nayarit is also included. [ABSTRACT FROM AUTHOR]

Quercus gambelii Nutt. is a widespread white oak (Quercus, subgenus and section Quercus, subsection Gambelieae) in the southern Rocky Mountain region of the United States, extending to west-central Chihuahua in the Sierra Madre Occidental of Mexico. Quercus arizonica Sarg., rather distantly related (subsection Glaucoideae), has a more southern distribution in the United States, and extends through the Sierra Madre into Durango. In the southwestern United States hybrids between Q. gambelii and several white oaks, including Q. arizonica, are very common, often forming a major portion of the lower elevation oak vegetation, particularly in New Mexico. These hybrids are known in general as Q. x undulata Torr., pro sp. A plant very similar to Q. x undulata, Q. lesueuri C. H. Muller, was collected by Harde LeSueur at "El Salto de Babicora", in west-central Chihuahua, in 1937. It has not been collected since. An oak similar to Q. lesueuri was collected by the author in the nearby Sierra Catarina where it is sympatric with Q. gambelii and Q. arizonica. El Salto de Babicora was determined to be located north of the town of Madera. In this canyon Q. gambelii and Q. arizonica are common. Quercus lesueuri and the newly collected hybrid from the Sierra Catarina are shown to be strongly similar to Q. x undulata and intermediate between Q. arizonica and Q. gambelii through the use of the same six leaf characters (leaf width, relative depth of indentations of leaf margin, conspicuousness of intercostal reticulum, number of major secondary veins, number of rays per stellate hair, curliness of hairs) that Tucker used to assess intermediacy of certain collections to the putative parents Q. gambelii and Q. arizonica. In this paper Q. lesueuri is demonstrated to be part of this hybrid complex. Taxonomically it should be recognized as Q. x lesueuri C. H. Muller, pro sp., and to be considered as a synonym of Q. x undulata, sensu lato. [ABSTRACT FROM AUTHOR]

In this paper a general overview of the taxonomic and floristic knowledge of the family Cucurbitaceae in Mexico is presented. The family is represented in this country by 137 taxa (species and infraspecific categories), belonging to 38 genera of its two subfamilies (Zanonioideae and Cucurbitoideae). Thirteen of the taxa are mainly crops for human consumption, the rest growing wild, of which more than 50% are endemic to relatively small areas of the country. Some of the wild taxa are closely related to crops of worldwide importance, and several are used mainly in folk medicine in various regions of the country. [ABSTRACT FROM AUTHOR]

Commelina nivea López-Ferrari, Espejo et Ceja, and Commelina rzedowskii López-Ferrari, Espejo et Ceja, two white flowered species are described and illustrated in this paper. The former is known only from Las Adjuntas, municipio of Pueblo Nuevo in the state of Durango and the other was collected in the neighborhood of Tenería, municipio of Tejupilco in the state of México. [ABSTRACT FROM AUTHOR]