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Cacti Species (cactus + species)
Selected AbstractsBiogeographic analysis of endemic cacti of the Sierra Madre Oriental, MexicoBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 2 2009HAMLET SANTA ANNA DEL CONDE JUÁREZ The distribution of cacti species that inhabit the Sierra Madre Oriental (SMO) was analysed. Grid-cells were analysed using parsimony analysis of endemicity (PAE) and endemism indices. Areas characterized by their diagnostic species were determined, aiming to propose areas for the conservation of threatened cacti. Distributional data were obtained from 1936 herbarium specimens, electronic information, and from field collections. Eight areas of endemism and three main clades were obtained from the grid-cell analysis. Areas obtained from the endemism indices are very similar to those obtained with the PAE, but differ in the association of grid-cells. PAE showed endemism patterns indicating that southern and central sections of the SMO province are the areas richest in geographically-restricted species. The results obtained with different endemism indices detected more or less the same areas, although the importance level is different. The corrected weighted endemism index can be considered as a reliable measure of endemism because it is unrelated to species richness. A regionalization of the SMO in three subprovinces is suggested, supported by characteristic cacti taxa and the existence of natural barriers. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 97, 373,389. [source] Estudio Fenológico de Cactíceas en el Enclave Seco de la Tatacoa, Colombia,BIOTROPICA, Issue 3 2000Adriana Ruiz RESUMEN Durance un año se realizó el estudio fenológico de tres cactáceas columnares Stenocereus griseus (Haw.) Britton & Rose, Pilosocereus sp., Cereus hexagonus (L.) Mill., y una cactácea decumbente, Monvillea cf. smithiana (Britton & Rose) Backeberg., en el enclave seco interandino de La Tatacoa, Colombia. Los polinizadores y/o dispersores de las cactáceas fueron capturados mensualmente y se recolectaron las muestras fecales para la identificatión de los granos de polen y las semillas de los frutos consumidos. La floración de todas las especies fue prolongada y mostraron patrones bimodales, multimodales, o irregulares. La fructificación en todas las especies también se extendió durante todo el año, con un desfase de dos meses con respecto a la floración. Aunque no se encontró una correlatión significativa entre los valores mensuales de precipitatión y la producción de flores y frutos, la floración durante la época seca fue mayor en S. griseus, mientras que Pilosocereus sp. y C. hexagonus mostraron los valores más altos durante la época de lluvias. La productión de frutos también fue estacional, con un incremento durante la época de lluvias para S. griseus y C. hexagonus. La floración y fructificatión en M. cf. smithiana no mostraron diferencias significativas entre la época seca y la lluviosa. Los murciélagos Glossophaga longirostris, Carollia perspicillata, Sturnira lilium y algunas aves como Melanerpes rubricapillus (Picidae) y Mimus gilvus (Mimidae), y una mariposa nocturna (Sphingidae), fueron algunos de los polinizadores y/o consumidores de estas especies de cactáceas. ABSTRACT A one-year phenological study of three columnar cacti, Stenocereus griseus (Haw.) Britton & Rose, Pilosocereus sp., Cereus hexagonus (L.) Mill., and a decumbent cactus Monvillea cf. smithiana (Britton & Rose) Backeberg., was carried out in the Andean arid region of La Tatacoa, Colombia. Pollinators and/or dispersers of the cacti species also were studied monthly, and fecal samples were collected for the identification of pollen and seeds. The flowering of all species was prolonged and showed bimodal, multimodal, or irregular patterns. Fruiting in all species also was prolonged and followed flowering with a lag of less than two months. Although there were no simple correlations between rainfall and flowering or fruiting, flower production during the dry season was higher for 5. griseus, while Pilosocereus sp. and C. hexagonus showed higher flower production during the wet season. Fruit production was also seasonal, with higher production during the wet season for 5. griseus and C. hexagonus. The patterns of flowering and fruiting in M. cf. smithiana showed no relationships with dry and wet seasons. The bats Glossophaga longirostris, Carollia perspicillata, Sturnira lilium, the birds Melanerpes rubricapillus (Picidae) and Mimus gilvus (Mimidae), and moths of the family Sphingidae, were identified as pollinators and/or fruit consumers of these cacti species. [source] Habitat restriction in Mammillaria pectinifera, a threatened endemic Mexican cactusJOURNAL OF VEGETATION SCIENCE, Issue 6 2003José Alejandro Zavala-Hurtado Dávila-Aranda et al. (1993) Abstract. This study deals with the habitat restriction of Mammillaria pectinifera, a threatened cactus species, confined to a few low density localities of the Tehuacán valley in tropical Mexico. We analysed the patterns of presence/absence of M. pectinifera in relation to the presence/absence of 48 other plant species, and the variation of environmental factors in 120 sampling plots. A Principal Components Analysis revealed a clear segregation between plots with and without individuals of M. pectinifera. A classification analysis resulted in four groups: two with low prevalence and two with high prevalence of M. pectinifera. Paired comparisons between plots with and without M. pectinifera allowed the characterization of its patterns of occurrence related to the variation of environmental factors. M. pectinifera was found on deep alkaline soils with relatively high surface stoniness and high water retention capacity, showing low species richness compared with plots where it was absent. The limited distribution of M. pectinifera in the Tehuacán Valley seems to be related to particular requirements of this species, being restricted to certain suitable habitat patches. Nevertheless, it is likely that other aspects, such as poor dispersal and establishment abilities, or biotic interactions could be associated with the observed patterns. [source] PRIMER NOTE: Isolation and characterization of polymorphic microsatellite markers in Galapagos prickly pear (Opuntia) cactus speciesMOLECULAR ECOLOGY RESOURCES, Issue 3 2007P. HELSEN Abstract The Opuntia (prickly pear) genus contains over 200 species. Six of them are endemic to the Galapagos archipelago. Although these cacti are ,keystone' species of the Galapagos' semi-arid ecosystem, they have never been studied in detail. Because of their current threatened status and their important role in the ecosystem, we developed 16 microsatellite markers to study the population genetic structure of some of these species. These markers display a high level of polymorphism with numbers of alleles per locus ranging from six to 53. Results also revealed possible polyploidy in these cacti. [source] | ||||||||||