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In Mexico, plants with crassulacean acid metabolism (CAM) are part of the Mexican culture, have different uses and are even emblematic. Unfortunately, only a small fraction of the Mexican CAM plants has been studied physiologically. For this review, the following questions were considered: What ecophysiological studies have been conducted with CAM species native to Mexico? What ecophysiological processes in Mexican CAM plants are the most studied? What type of ecophysiological studies with CAM plants are still needed? A database of scientific studies on CAM plant species from Mexico was documented, including field and laboratory works for species widely distributed, and those studies made outside Mexico with Mexican species. Physiological processes were grouped as germination, photosynthesis, and water relations. Most studies were done for CAM species of Cactaceae, Bromeliaceae, Asparagaceae and Orchidaceae, andmost ecophysiological studies have been done on germination of cacti. Field and laboratory studies on photosynthesis and water relations were mostly for terrestrial cacti and epiphytic bromeliads. There were few physiological studies with CAM seedlings in Mexico and few studies using stable isotopes of water and carbon of CAM plants in the field. More field and laboratory studies of physiological responses and plasticity of CAM plants to multiple stress factors are required to model plant responses to global climate change. In general, more physiological studies are essential for all CAM species and for species of the genus Clusia, with C3-CAM and CAM members, which can become ecologically important under some climate change scenarios.

Echeandia flavescens (Asparagaceae) se registra por primera vez para Sudamérica (Colombia y Venezuela), mientras que Echeandia denticulata y Echeandia durangensis se reducen a la sinonimia de Echeandia flavescens. Echeandia flavescens es una entidad poliploide, por lo que exhibe una morfología muy variable, así como una amplia distribución geográfica. Se discute la disyunción geográfica de esta especie, se entregan datos sobre su ecología y posibles polinizadores en Colombia y se presentan algunas relaciones con especies morfológicamente afines.

Se describe e ilustra Nolina excelsa, especie nueva del estado de Oaxaca. Esta especie se compara con N. parviflora, de la cual difiere en la altura de los individuos, la longitud y numero de hojas por roseta; los tépalos con una linea media longitudinal de color morado; el tamaño del fruto y la forma, tamaño y ornamentación de las semillas.

Semillas de Asparagus officinalis L. germinaron bajo períodos controlados de luz y en diferentes rangos. La germinación alcanzó su punto óptimo a 25°C. No se observó ningún resultado estadísticamente significativo en la tasa de germinación de las semillas bajo diferentes períodos de luz.