Repositorio Institucional de INECOL (Instituto de Ecología)
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Hongos de Zoncuantla, Veracruz I. Nuevos registros para Veracruz y Mexico
Get PDFSe presenta un estudio de seis especies de hongos, de los que uno es nuevo registro para México (Pluteus xylophilus var. xylophilus), tres son nuevos para el estado de Veracruz y dos son nuevos para Zoncuantla. Las especies pertenecen a las familias Thamnidiaceae (Zygomycotina), Xylariaceae (Ascomycotina) y Corticiaceae, Pluteaceae y Strophariaceae (Basidiomycotina)
Dos especies nuevas de Valeriana (Valerianaceae) del centro de México
Get PDFSe describen como nuevas dos especies de Valeriana, de distribución aparentemente muy restringida. V. emmanuelii, que procede de dos localidades ubicadas en el extremo sur del municipio de Morelia, Michoacán, es cercana a V. retrorsa Fern. y a V. densiflora Benth. Del estado de Querétaro se reconoce a V. zamoranensis, perteneciente a la serie Ceratophyllae, que sólo se registra de la parte más alta del Cerro Zamorano; al parecer está relacionada con V. zapotecana Barrie y con V. otomiana Barrie
Gamma diversity: derived from and a determinant of alpha diversity and beta diversity. An analysis of three tropical landscapes
Get PDFUsing three taxonomic groups of beetles we examine how alpha and beta diversity influence the species richness of a landscape (gamma diversity), and vice versa. That is, how the species richness of a landscape ? which is a historical and biogeographical phenomenon ? contributes to the values of alpha diversity (1) at a given site, (2) in a community, (3) in terms of cumulative species richness by community, and also contributes to (4) the intensity of species exchange between communities. To explore this question, we used two subfamilies of Scarabaeoidea: Scarabaeinae and Geotrupinae, and the family Silphidae. In all analyses these three taxonomic groups are considered as a single indicator group: the copronecrophagous beetles. Information is also included on the subfamily Aphodiinae (Scarabaeoidea), coprophagous beetles not included in the indicator group. Several types of vegetation located in three landscapes (tropical, transition and mountain) were studied, and these are located along an altitudinal gradient in the central part of the state of Veracruz, Mexico. We base this study on the following concepts. The alpha diversity of an indicator group reflects the number of species that use a given environment or resource in a given place or community. Spacial beta diversity is related to the response of organisms to spatial heterogeneity. Gamma diversity depends primarily on the historical and geographic processes that operate on the mesoscale level and is also affected by alpha and beta diversity. It is on this scale of landscape that human actions, such as the modification and fragmentation of vegetation, have their most important effects. These are, however, often beyond the scope of ecological analyses carried out on a local scale. In the three landscapes, sampling was carried out regularly at 67 sites, with complementary sampling at another 69 sites. Twenty-six types of vegetation communities were studied. A total of 16,152 specimens representing 60 species were captured (52 species of Scarabaeinae, 4 Geotrupinae and 4 Silphidae). In the tropical landscape the community richest in species was low deciduous forest. In the transition landscape, cloud forest was the richest. Each of these communities is the most representative of their respective altitudinal bands. In contrast, the greatest species richness in the mountain landscape occurred in the mountain grasslands and pastures; types of community favoured by or even created by human intervention. This is explained by the expansion of heliophilous species from the Mexican High Plateau into these areas. In the tropical landscape the species richness of the pastures is similar to that of its forests, but with a partially different composition which is characterized by the dominance of heliophilous and coprophagous species; the latter, in addition to the more ubiquitous species that are shared with the tropical forest. In the transition landscape the cloud forest and the coffee plantations with polyspecific shade are important in the context of conserving the fauna. This type of community offers arboreal cover and occupies the majority of this landscape, allowing the groups of insects studied to move between remnant fragments of cloud forest. On the landscape scale but not locally, the fragmentation of natural communities does not appear to have reduced the number of species for the beetles of the indicator group. In each landscape disturbance by human activity appears to have been overcome for distinct reasons. In the tropical landscape we find the heliophilous beetle fauna characteristic of pastures, and this has increased by two species of recent invaders. In the transition landscape, the coffee plantations with polyspecific shade create a communication matrix, while in the mountain landscape the expansion of the mountain pastures has made conditions more favourable for heliophilous species. These results are not necessarily expected for other groups of organisms
TIGRIDIA GRACIELAE (TIGRIDIEAE: IRIDACEAE), A NEW SPECIES FROM MEXICO
Get PDFTigridia gracielae (Tigridieae: Iridaceae), from the state of México, is a new species morphologically similar to T. venusta, from the state of Michoacán. Tigridia gracielae differs from T. venusta in having shorter and narrower tepals, a longer staminal column, anthers fertile along their full length and shorter style branches. Both species share habitat preference for the shaded understory of fir and pine forests near 3000 m elevation
Micromorfología de la lema en Cathestecum (Poaceae: Chloridoideae: Boutelouinae)
Get PDFDada la utilidad taxonómica que presentan los caracteres de la epidermis de la lema y la escasez de información pertinente para el género Cathestecum, se examinan, describen y comparan estas características con aquellas presentadas por géneros afines de la subtribu Boutelouinae, con el fin de dilucidar sobre los posibles rasgos con valor taxonómico. Los resultados más significativos muestran la presencia de papilas en C. tamaulipense, C. erectum y C. brevifolium var. sonorense, la ausencia de aguijones y células de corcho en C. brevifolium y la ausencia de cuerpos de sílice en todas las especies de Cathestecum. Los géneros afines Buchloë, Soderstromia, Griffithsochloa, Pentarrhaphis y Bouteloua, representados en su mayoría por una sola especie, excepto Bouteloua y Pentarrhaphis, presentan abundantes papilas (no observadas en Bouteloua eludens ni en Griffithsochloa multifida) y células de corcho. Los cuerpos de sílice sólo se observaron en Buchloë dactyloides. Se concluye que algunas características micromorfológicas estudiadas pueden considerarse de valor taxonómico para separar las especies de Cathestecum, así como establecer, junto con otras fuentes de evidencia morfológicas, relaciones entre los taxa de la subtribu Boutelouinae
Hongos de Zoncuantla, Veracruz I. Nuevos registros para Veracruz y México
Get PDFSe presenta un estudio de seis especies de hongos, de los que uno es nuevo registro para México (Pluteus xylophilus var. xylophilus), tres son nuevos para el estado de Veracruz y dos son nuevos para Zoncuantla. Las especies pertenecen a las familias Thamnidiaceae (Zygomycotina), Xylariaceae (Ascomycotina) y Corticiaceae, Pluteaceae y Strophariaceae (Basidiomycotina)
Nota sobre la presencia de Phytolacca rugosa (Phytolaccaceae) en la flora del Valle de México
Get PDFSe registra para la flora del Valle de México a Phytolacca rugosa A. Braun & C. D. Bouché. La especie se ha encontrado en bosque de Quercus perturbado en Cañadas de Santa Fe, en las cercanías de San Lorenzo Tepeaculco, Delegación Cuajimalpa de Morelos y en Bosques del Pedregal, Delegación de Tlalpan, Distrito Federal. También se registran en esta planta anomalías florales semejantes a las observadas en P. icosandra L
Traditional Uses and Abuses of Hallucinogenic Fungi: Problems and Solutions
Get PDFA review of the diversity and the traditional use of the hallucinogenic or neurotropic fungi is given, as well as discussion of the abuse of these fungi through recreational use by young people around the world. These fungi, especially those belonging to genus Psilocybe, have wide distribution in the world, and they are very easy to obtain by culture. As a solution, it is proposed to reduce the recreational use of these fungi through official public programs launched by governments to show how dangerous the continued use of mushrooms is
Nota sobre la presencia de Portulaca rubricaulis H.B.K. (Portulacaceae) en la Península de Yucatán
Get PDFPortulaca rubricaulis H.B.K. es una especie que se distribuye principalmente en la zona del Mar Caribe, desde Florida hasta la parte norte de Sudamérica, y de la cual se tenían escasos registros como integrante de la flora de la Península de Yucatán. No obstante, la revisión de los herbarios mexicanos CICY, ENCB, MEXU, UCAM y XAL puso de manifiesto que esta especie se encuentra ampliamente distribuida y bien colectada en la parte septentrional de la zona de estudio. Aún más, se detectó material proveniente de la porción suroeste del estado de Campeche, lo cual posiblemente indique que P. rubricaulis esté efectuando un movimiento de dispersión del norte de la Península hacia las costas sureñas del Golfo de México. Adicionalmente, en el presente trabajo se anexa una clave de identificación para las especies conocidas de Portulaca de la Península de Yucatán
Infection of Ceratium furca by the parasitic dinoflagellate Amoebophrya ceratii (Amoebophryidae) in the Mexican Pacific
Get PDFParasitism within dinoflagellates is a widespread and well-documented phenomenon. Parasitic dinoflagellates of the genus Amoebophrya commonly infect free-living toxic, and non-toxic dinoflagellates species which may cause harmful red tides. Infections of Ceratium furca by A. ceratii were observed in red tides samples collected in the northwest coast of Baja California between 30°01'05'' N, 115°51'16'' W and 31°09'33'' N, 116°31'09'' W. This is the first record of this particular parasitic dinoflagellate in Mexican Pacific waters. There were mainly three dinoflagellate species causing this particular seawater discoloration: a Gymnodinium-like dinoflagellate, Ceratium furca, and Akashiwo sanguinea. These reached concentrations as high as 560 000, 762 600, and 395 400 cells L-1, respectively. During the bloom, surface water temperature ranged between 13 and 17°C. Seawater salinity ranged from 33.2 to 33.8 psu. About 1.5% of the individuals of C. furca observed were infected by the intracellular parasite dinoflagellate Amoebophrya ceratii. This parasite was observed mainly inside specimens of Ceratium furca and very few specimens of Ceratium macroceros. In general, individuals of C. furca were partially or totally deformed. Infections by A. ceratii could delay or inhibit the dinoflagellate blooms as infected dinoflagellates become reproductively incompetent