Scielo RSS <![CDATA[Revista chilena de historia natural]]> vol. 88 num. lang. en <![CDATA[SciELO Logo]]> <![CDATA[<b><i>Suaeda foliosa </i></b><b>Moq. (Caryophyllales: Amaranthaceae) first record of the genus and species for Valparaíso Region, Chile</b>]]> BACKGROUND: The purpose of this paper is to present the finding of Suaeda foliosa in El Yali National Reserve, Chile. With this finding, the southern limit of the distribution is displaced from the current position at 31° S, 300 km southward. FINDINGS: In this work, we found this species on the banks of the Colejuda lagoon, 33° 45' S, which belongs to a body of hypersaline seasonal water found inside the protected area distinguished as a Ramsar site (No. 878). The determination of the genus and species was achieved by comparing with herbarium material deposited in the National Herbarium SGO Natural History Museum in Santiago de Chile. Once we identified the species, the collected material was deposited in the referred Herbarium (SGO 163975). pH, salinity, and conductivity of the water column and soil adjacent the three protected lagoons are compared, discussing the unique conditions of the lagoon Colejuda that may explain the presence of S. foliosa only in their environment and not in other water bodies. CONCLUSIONS: It can be concluded that El Yali wetland system harbors the S. foliosa southernmost population of the Americas. <![CDATA[<b>Invasion of North American beaver <i>(Castor canadensis) </i>in the province of Magallanes, southern Chile</b>: <b>comparison between dating sites through interviews with the local community and dendrochronology</b>]]> BACKGROUND: Twenty beavers Castor canadensis (Castoridae) were initially introduced in the Argentinean portion of Tierra del Fuego Island, from where they have occupied most of the Fuegian Archipelago and even reached the continent. This invasion is causing great damage to the subantarctic forest ecosystems, and it is not known how fast the species is spreading. While there is an estimation of this advance using interviews, it is not known how reliable these are and they cannot be made in remote areas. On the mainland, where beavers were present, their date of arrival was estimated using interviews and dendrochronology, and the dates obtained by both methods were compared for each site. RESULTS: Differences were found among the groups of respondents, according to property size, in their ability to detect changes in the environment made by beavers. The dates of arrival estimated through dendrochronology are 23 years prior to those determined through surveys, and they generate a potential route of arrival from the Fuegian Archipelago and migration in the mainland. This route is more parsimonious than the route of dispersal generated through interviews. CONCLUSIONS: Since it was determined that there is no relationship between the dates estimated through surveys and dendrochronology, it is not possible to determine how much lag there is from the time when changes in the environment are produced by beavers and the time when people notice this change. Our results indicate that this lag may not be constant among different groups of people. <![CDATA[<b>Evolution of hematophagous habit in Triatominae (Heteroptera: Reduviidae)</b>]]> All members of Triatominae subfamily (Heteroptera: Reduviidae), potential vectors of Trypanosoma cruzi etiologic agent of the Chagas disease, feed on blood. Through evolution, these bugs have fixed special morphological, physiological, and behavioral aptations (adaptations and exaptations) adequate to feed on blood. Phylogeny suggests that triatomines evolved from predator reduvids which in turn descended from phytophagous hemipterans. Some pleisiomorphic traits developed by the reduvid ancestors of the triatomines facilitated and modeled hematophagy in these insects. Among them, mouthparts, saliva composition, enzymes, and digestive symbionts are the most noticeable. However, the decisive step that allowed the shift from predation to hematophagy was a change of behavior. The association of a predator reduvid with nesting vertebrate (≈110 to 32 Ma) permitted the shift from an arthropod prey to a vertebrate host. In this work, we review the phylogeny and dispersion of triatomines and the current controversy over the monophyly or polyphyly of this group. We also discuss how these insects were able to overcome, and even have taken advantage of, diverse ancestral and physical barriers to adapt to sucking blood of nidicolous vertebrates. We provide a Spanish version of this work. <![CDATA[<b>Evidence that the house finch (<i>Carpodacus mexicanus) </i>uses scent to avoid omnivore mammals</b>]]> BACKGROUND: The detection of predator chemical cues is an important antipredatory behaviour as it allows an early assessment of predation risk without encountering the predator and therefore increases survival. For instance, since chemical cues are often by-products of metabolism, olfaction may gather information not only on the identity but also about the diet of predators in the vicinity. Knowledge of the role of olfaction in the interactions of birds with their environment, in contexts as important as predator avoidance, is still scarce. We conducted two two-choice experiments to explore 1) whether the house finch Carpodacus mexicanus can detect the chemical cues of a marsupial predatory mammal, the common opossum (Didelphis marsupialis), and 2) whether its response to such cues is influenced by the recent diet of this omnivorous predator, as this would increase the accuracy with which the risk of predation is assessed. RESULTS: House finches avoided the area of the apparatus containing the scent of the predator, and this effect did not depend on the recent diet (bait used to lace the traps) of the predator. CONCLUSIONS: Our results provide clear evidence that house finches detect and use the chemical cues of predators to assess the level of predation risk of an area and avoid it. <![CDATA[<b>Comparative study of moss diversity in South Shetland Islands and in the Antarctic Peninsula</b>]]> BACKGROUND: This paper presents a comparative study of moss diversity in three collection sites in the South Shetland Islands (King George, Elephant, and Nelson Islands) and one in the Antarctic Continent (Hope Bay, Antarctic Peninsula). In the King George, Elephant, and Nelson Islands, the collections were done in ice-free areas during the austral summers of years 1988,1989, 1990, 1991, 1992, and 1994. In Hope Bay, the collections were done in the 2009 summer (February). All collections were deposited in the HCB (Chaves Batista Herbarium). FINDINGS: The King George Area is the most diverse area and the Hope Bay has the lowest diversity stats. The diversity stats for each region and the similarities between both are presented. CONCLUSION: This results suggested that harder climatic conditions determine lower diversity for the bryoflora.<hr/>En este trabajo se presenta un estudio comparativo de tres puntos de muestreo de musgos en las Islas Shetland del Sur (Isla Rey Jorge, Elefante y Nelson) y el Continente Antártico (Bahía Esperanza, Península Antártica). En las Islas King George, Elefante y Nelson, se tomaron muestras en las zonas libres de hielo durante los veranos australes de años 1988, 1989, 1990, 1991, 1992 y 1994. Hope Bay, las colecciones se hicieron en el verano austral de 2009 (febrero). Todas las colecciones fueron depositadas en el herbario de HCB (Herbario Chaves Batista). Los índices de diversidad para cada región se presentan, así como la similitud entre ellos. <![CDATA[<b>Influence of forest type and host plant genetic relatedness on the canopy arthropod community structure of <i>Quercus crassifolia</i></b>]]> BACKGROUND: Quercus crassifolia is an oak species with characteristics of foundation species, which is a canopy dominant element of different forest types that supports a wide diversity of associated species. Therefore, it is an excellent system to address important ecological questions. We analyzed the effect of individual genetic relatedness of the host plant, forest type (Abies-Quercus, Quercus-Pinus, and Quercus forest), and season (dry vs. rainy) on the canopy arthropod community structure. Thirty oak canopies were fogged (five individuals/season/forest type). RESULTS: We identified 442 arthropod species belonging to 22 orders. The highest values of density, diversity, and richness were recorded during the rainy season for each forest type. Also, the non-metric multidimensional scaling (NMDS) analysis showed a separation of the host tree species for each forest type. During the rainy season, the highest values of density, diversity, and richness in each forest type were recorded. A separation of host tree was found for each forest type. In general, diversity and richness of canopy arthropods showed the following pattern: Abies-Quercus > Quercus-Pinus > Quercus, while density showed an inverse pattern. An increase of the diversity of canopy arthropods is significantly related to an increase of host plant genetic diversity, independently of the type of forest and of the season. CONCLUSIONS: In terms of conservation, if arthropod species respond to genetic differences among host plants, it becomes important to conserve genetic diversity of foundation species, since it is fundamental to preserve diversity of their associated arthropod communities. <![CDATA[<b>Morphological characterization under different ecological habitats and physical mapping of 5S and 45S rDNA in <i>Lilium distichum </i>with fluorescence <i>in situ </i>hybridization</b>]]> BACKGROUND: This study was performed to investigate the phenotypic, karyomorphological, and habitat environment characteristics of Lilium distichum that grows naturally in South Korea. Currently, this species follows limited distribution areas and its natural populations are at the brink of extinction mainly due to fragmentation or destruction its natural habitat. RESULTS: This species was distributed between approximately 1,000 and 1,500 m above sea level with an average temperature of 22°C. The soil characteristics surrounding the natural habitats included loamy and silt loam soils having organic matter content (10.82%), pH (5.22), electrical conductivity (EC) (0.37 dS/m), total nitrogen (0.45%), and cation exchange capacity (34.3 cmol+/kg). The peak period of blossoming was between 27 July and 1 August. The maximum number of flowers was observed in Mount Deogyu (2.8), whereas the minimum number of flowers was observed in Mount Jiri (1.3) and Mount Seorak (1.2). Results regarding the number of verticillate leaf, bract counts, and verticillate leaf length and width were highest in Mount Odae, while lowest in the Mount Seorak region. The chromosome complement of L. distichum is 2n = 2x = 24; the length of somatic metaphase chromosomes ranges from 17.01 ± 0.32 μm (chromosome 10) to 32.06 ± 0.35 μm (chromosome 1) with a total length/genome of 261.92 μm. In L. distichum, the presence of 1 pair (two loci) of 5S ribosomal DNA (rDNA) and 8 pairs (16 loci) of 45S rDNA was revealed on metaphase chromosomes. One pair of 5S rDNA signal was observed in interstitial region of long arm of chromosome 3 which co-occurred with 45S rDNA. Among the eight pairs of 45SrDNA, three pairs of 45S rDNA signals were observed in short arm of chromosome (chromosome 2, 6, and 7) which were located close to centromere. The other five pairs of 45S rDNA signals were positioned in the interstitial region of long arm (chromosome 3, 4, 5, 10, and 11. CONCLUSIONS: This study provides baseline information regarding the effective exploitation and use of L. distichum resources for breeding research to be used as cut flower and potted plants.