Scielo RSS <![CDATA[Revista chilena de historia natural]]> vol. 88 num. lang. es <![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.