Gastón Guzmán

THE KNOWN MORELS IN MEXICO, A DESCRIPTION OF A NEW BLUSHING SPECIES, MORCHELLA RUFOBRUNNEA, AND NEW DATA ON M. GUATEMALENSIS

A critical analysis of the known species of Morchella from Mexico, including M. angusticeps, M. costata, M. elata, M. esculenta (M. conica; M. crassipes, M. rotunda), M. guatemalensis and M. umbrina, is presented. In addition, M. rufobrunnea is described as a new species from the State of Veracruz. Morchella rufobrunnea belongs to the blushing species, a fourth group of species in the genus proposed by the au- thors. The blushing species also include M. guate- malensis and M. rigidoides, and all three species are confined to the tropics or subtropics. Morchella rigi- doides is known only from New Guinea, and M. gua- temalensis only from Guatemala and Mexico. The new species differs in the form and color of the ascomata, length of the alveolae, and the color of staining. A revision of the microscopic features of M. guatema- lensis is made based on recent collections from Mex- ico and Guatemala. After a comparison of the asci, ascospores and paraphyses of M. guatemalensis with those of M. rufobrunnea and other close species, it is concluded that microscopic features, except the width of the paraphyses in some cases, are not im- portant in the taxonomy of the genus. The form and color of the ascomata, the position of the ribs, the length of the alveolae, and the staining are the most important taxonomic features in Morchella. A key to the seven known species of Morchella in Mexico is

The genus Psilocybe : a systematic revision of the known species including the history, distribution, and chemistry of the hallucinogenic species

The genus Psilocybe: a systematic revision of the known species including the history, distribution, and chemistry of the hallucinogenic species , The genus Psilocybe: a systematic revision of the known species including the history, distribution,... , مرکز فناوری اطلاعات و اطلاع رسانی کشاورزی

Scleroderma stellatum versus Scleroderma bermudense: the status of Scleroderma echinatum and the first record of Veligaster nitidum from the Virgin Islands

The type of Scleroderma stellatum from Brazil exhibits a sharp echinulate, dark brown peridium, and the type of S. bermudense from Bermuda has a peridium that is loosely woven and fibrillose, whitish to pale brownish. These characters indicate two independent species. This information is contrary to that of Guzmán in 1970, who interpreted S. bermudense to be a synonym of S. stellatum based on the similar spores. Scleroderma echinatum from Borneo and Panama, as recently discussed by Guzmán and Ovrebo, also has an echinulate, dark brown peridium and is a synonym of S. stellatum. All these fungi have a stellate dehiscence. New records of S. bermudense from the Greater Antilles and Mexico’s Pacific Coast, and Veligaster nitidum from Virgin Islands also are discussed.

Some distributional relationships between Mexican and United States mycofloras.

The relationships among more than 200 species of higher fungi of eastern and western United States and Mexico are discussed. Four types of relationships between both mycofloras are established: (1)...

Description and chemical analysis of a new species of hallucinogenic Psilocybe from the Pacific Northwest.

In the course of our research on hallucinogenic fungi (1, 7), and our work on a world monograph of the genus Psilocybe, we have discovered an interesting new hallucinogenic species. The mushroom was first collected on the campus of the University of Washington in Seattle, and has since been found in several other sites in western Washington and Vancouver, British Columbia. Since this species is very common in western Washington, and is widely used as a recreational drug, it is surprising that it has not been previously reported.

Variation, distribution, ethnomycological data and relationships of Psilocybe aztecorum, a Mexican hallucinogenic mushroom.

SUMMARYBased upon data obtained from a study of the type as well as from Heims and Singer and Smiths descriptions and from several fresh specimens collected by the author, Psilocybe aztecorum is ...

Bovista sclerocystis, a new species from Mexico

Bovista sclerocystis is described as a new species. It was found in Mexico, growing on rich soil of a tropical forest. It belongs to section Globaria, series Albosquamosa. The most striking character of this taxon is the exoperidium composed of polymorphous mycosclereids.

Automatic geomorphometric analysis for digital elevation models

We present an approach to perform geomorphometric analysis for Digital Elevation Models (DEM) to obtain the Cartographic Knowledge Domain (CKD) of the landscapes. CKD is oriented to represent the essential properties of DEM by means of concepts. These properties are obtained by analyzing the terrain topography. This analysis is based on two classifications: landform and topographic ruggedness. The approach involves the following raster layers: slope, profile curvature and plan curvature (primary attributes), which have been built to identify the intrinsic properties of the landscape. We use a multi-valued raster to integrate the primary attributes of DEM to generate the landform classification layer in order to find the terrain characteristics of the water movement. The topographic ruggedness is used to express the amount of elevation difference between adjacent cells of DEM. The topographic ruggedness is presented by means of Terrain Ruggedness Index (TRI). This work is oriented to support subsequent processes. The method has been implemented into Geographical Information System - Arclnfo, and applied for Tamaulipas State, Mexico.

On the Origin of the Genus Psilocybe and Its Potential Ritual Use in Ancient Africa and Europe1

On the Origin of the GenusPsilocybeand Its Potential Ritual Use in Ancient Africa and Europe. The role of altered states of consciousness in the production of geometric and figurative art by prehistoric cultures in Africa and Europe has been hotly debated. Helvenston and Bahn have tried to refute the most famous hypothesis, Lewis-Williams’ neuropsychological model, by claiming that appropriate visual hallucinations required the ingestion of LSD, psilocybin, or mescaline, while arguing that none of these compounds were available to the cultures in question. We present here mycological arguments that tell another story. A prehistoric worldwide distribution of the mushroom genus Psilocybe, and therefore of psilocybin, is supported by the existence of endemic species in America, Africa, and Europe, the disjunct distribution of sister species, and the possibility of long-distance spore dispersal. It is more difficult to point to instances of actual prehistoric ritual use in Africa and Europe, but there are a growing number of suggestive findings.Sobre el Origen del GéneroPsilocybey su Uso Ritual Potencial en África y Europa Antiguas. El papel de los estados alterados de conciencia en la producción de arte geométrico y figurativo por culturas prehistóricas en África y Europa ha sido fuertemente debatido. Helvenston y Bahn han tratado de refutar la hipótesis más famosa, el modelo neuropsicológico de Lewis-Williams, al afirmar que las alucinaciones visuales apropiadas requieren la ingestión de LSD, psilocibina o mezcalina, al mismo tiempo que sostienen que ninguno de estos compuestos estaba disponible para las culturas en cuestión. Presentamos aquí argumentos micológicos que cuentan una historia diferente. La distribución prehistórica mundial del hongo del género Psilocybe, y por ende de la psilocibina, es apoyada por la existencia de especies endémicas en América, África y Europa, por la distribución disyunta de especies hermanas, y por la posibilidad de dispersión de esporas a larga distancia. Es más difícil señalar ejemplos de uso ritual prehistórico reales en África y en Europa, pero hay un número creciente de hallazgos sugerentes.

Taxonomy and chemical aspects of Psilocybe wrightii from southern Brazil.

Psilocybe wrightii (Strophariaceae, Agaricales), a subtropical and hallucinogenic species known only from southern Brazil and northern Argentina, is confirmed to contain psilocybin and psilocin. Detailed description of southern Brazilian specimens, chemical analysis using gas chromatography of the basidiomes, and discussion of its taxonomy are presented.