Se reporta la presencia de la especie Jenynsia multidentata en Chile central, avistada en agosto de 2008 en la localidad de Peñaflor. Durante 2009 se registra en la confluencia del estero Puangue y el río Maipo, extendiendo su distribución a un amplio sector de este estero. Jenynsia multidentata corresponde a la 26a especie íctica introducida al país.

Se registra Anelosimus lorenzo para Uruguay, constituyendo el hallazgo más austral de la especie. El presente registro confirma la inusual presencia de una araña social para una zona de clima templado. Con este nuevo reporte, el número de especies de Anelosimus conocidas para este país se eleva a tres.

The richness and composition of bird species in the Atacama desert located in the Far North of Chile, was studied between 1996 and 1998. Using lineal transects, the richness of bird species was evaluated in nine locations of the Atacama Desert, grouped into four ecological zones: Coastal Desert, Inland Desert, Marginal Tropical, and Altitude Tropical. Bird species richness totaled 80 species, belonging to 51 genera and 26 families. Total richness corresponded to 52% of historical descriptions of birdlife in the Chilean Far North desert. The ecological zones of the coastal and altitude tropical desert areas each have unique bird fauna elements. Insectivorous birds predominated over other trophic groups (40% of total species). The predominance of different trophic groups appears to depend on the type of feeding habitat used. Our results suggest that the variety of bird species in the Chilean Atacama Desert is determined by habitat heterogeneity and the immigration of species from zones, adjacent to the Atacama Desert.

The Siluriformes conservation state was quantified by means of the SUMIN index, composed by the sum of 12 outstanding variables for the species survival and/or conservation. An arranged list of the thirty -three Siluriformes species from the Ramsar Site was obtained based on a gradient of conservation necessity. The species were defined as Vulnerable of Maximum Priority: Pseudoplatystoma corruscans, P. f. fasciatum, Luciopimeloduspati and Hemisorubimplatyrhinchos; species Vulnerables of Special Attention: Oxydoras kneri, Ageneiosus valenciennesi, Sorubim lima, Platydoras costatus, Pterodoras granulosus, Sturisoma robustum, Trachydoras paraguayensis and Ageneiosus brevifilis. The remaining species, were qualified as Not Threatened: Corydoras paleatus, Pimelodus ornatus, Loricariichthys anus, Pimelodus albicans, P. maculatus, Hypostomus commersoni, Loricariichthys platymetopon, Pimelodus brevis, Paraloricaria vetula, Parastegophilus maculatus, Trachelyopterus striatulus, T. cf. galeatus, Bergiaria westermanni, Pimelodella laticeps, Liposarcus anisitsi, Otocinclus vittatus, Loricaria simillima, Parapimelodus valenciennis, Pimelodellagracilis, Auchenipterus osteomystax and Hoplosternum littorale.

In October (5-26^th) and December (17-24^th) of
2005, zooplankton samples were taken from 40 stations in the Coquimbo bay (29º
21’- 30º 15’ S) and the coastal area of Caldera (26º 46’- 27º 08’ S) (FIP
Project Nº 2004-45). All Emerita analoga larvae were taken from the
samples and their developmental stages, relative abundances, numerical dominance
and frequency of occurrence were determined. The segregated distribution of
different larval stages observed in the two sampling periods and locations, and
their relationship with the bathymetric distribution of adults on sandy beaches,
allowed determining the dispersion of this species. The distribution and
abundance of the larvae are related to the spawning possible areas. The early
stages were observed predominantly at stations in the coastal area of Coquimbo,
while more developed stages were seen in the open ocean. The highest abundances
of megalopas were observed in the northern area. In both areas the early stages
were most abundant and in Caldera the larvae of this species were less abundant
than in Coquimbo. Differences in developmental stage composition between the two
sampling seasons were detected. In October the more advanced stages were
dominant, while in December a similar trend to the one described for the
Coquimbo bay system was observed. Considering the distance from the nearest
sandy beaches; zoea 1 and 2 were the most abundant in closer ranges, zoea 3 and
4 showed maximum dispersion from the sandy beaches and zoea 5 and megalopas were
again found at shorter distances, demonstrating their return to the sandy
beaches in the coastal area.

Phylogenetic analysis of a fragment of the mitochondrial genome and qualitative and quantitative assessments of morphological variation suggest that, in its current conception, Thylamys pusillus (Desmarest, 1804) is a complex of at least three species. In the taxonomic arrangement proposed in this work, the populations in the Argentinean provinces of Entre Ríos and Corrientes are here referred to T. citellus (Thomas, 1912), while the small Thylamys that lives in the Argentinean Dry Chaco are provisionally referred to T.pulchellus (Cabrera, 1934). In our scheme, Thylamys pusillus is restricted to the Bolivian and Paraguayan Chaco and the vicinities of northern Formosa province in A rgentina. We provide emended diagnosis for T. citellus and T. pulchellus, together with detailed morphological descriptions and discuss their distinctiveness from other species of Thylamys. In addition, we included new distributional data.

The process of landscape transformation has been more intense and extended in the central depression of central and southern Chile than in the nearby mountain ranges. The original forest cover has almost disappeared; only small fragments persist inserted into a matrix of agroecosystems. This situation may influence the distribution of carnivorous mammals, depending on their degree of habitat specialization and home range size. The goal of this study was to evaluate, through the study of feces dsitribution, the habitat selection of the carnivore assemblage in a fragmented environment in southern Chile. We document the selective use of exotic forest plantations of Pinus radiata with a scrub understoiy by Puma concolor, Galictis cuja, and Lycalopex griseus. Leopardus guigna, despite not showing a statistically significant selection of the native forest, presents a greater number of records in this type of habitat. Habitat selection by the predators studied shows a variable degree of use of altered and fragmented environments. Surrounding forest plantations present an understoiy of native vegetation, which fits the requirement of most of the carnivores. The levels of spatial overlapping and the adequacy to new environments are discussed.

The number and identity of the species of black widow spiders of the genus Latrodectus that inhabit Chile remain unclear. Here we present results of taxonomic work based on morphologic and molecular characters of a large series of specimens collected throughout Chile, which aimed to assess Chilean Latrodectus diversity. Results show that all studied populations belong to a single species, for which the correct name is Latrodectus thoracicus Nicolet 1849. Therefore, we remove this taxon from the synonymy of L. mactans (Fabricius, 1775). In addition, we suggest that L. mirabilis (Holmberg, 1876) may be junior synonym of L. thoracicus. We recognize two species of black widows for continental Chile, L. thoracicus andi. variegatus Nicolet, 1849. We provided an emended diagnosis and comprehensive description of L. thoracicus as well as new locality records and novel data on its natural history. Given our results, we recommend the continued collecting specimens and more collection based taxonomic work as the only way of gathering a correct appreciation of Latrodectus diversity in southern South America.