1. Electrophysiological and morphological (retrograde axonal transport of horseradish peroxidase, HRP) experiments have been carried out in the cat in order to study the associative projections from area SI to ipsilateral SII. 2. Microelectrode recordings were performed in the forepaw focus of SII both in normal (64 units) and in SI-undercut (51 units) cats. 29.6% of the neurons recorded in the unoperated and 29.4% of those collected in the operated cats were excited by electric stimulation of the ipsilateral SI (forepaw focus). In both preparations almost all such units were endowed with large (either contra- or bilateral) receptive fields (RF). Cell population recorded in the SI-undercut cats showed no significant impairment to peripheral stimuli and/or changes in the size of the RFs. 3. From the forepaw focus of SI, 150 units have been recorded and tested by stimulation of the homologous focus of the ipsilateral SII. Eight of them were fired antidromically and thus identified as association cells. Their RFs were very small and located only in the digits of the contralateral forepaw. 4. Both single or multiple HRP injections were performed in SII. Retrogradely labelled cells were found in the ipsilateral SI. The great majority of association cells are pyramids and dwell mainly in layer III. In spite of the large diffusion of the exogenous reaction product in the injected SII and of the presence of retrogradely labelled cells anywhere in the ipsilateral thalamic VB complex, the distribution of association cells is unequal throughout SI since they strongly predominate in the digit zone of the forepaw representation.

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Antarctica currently has few non-native species, compared to other regions of the planet, due to the continent’s isolation, extreme climatic conditions and the lack of habitat. However, human activity, particularly the activities of national government operators and tourism, increasingly contributes to the risk of non-native species transfer and establishment. Trichocera (Saltitrichocera) maculipennis Meigen, 1888 (Diptera, Trichoceridae) is a non-native fly originating from the Northern Hemisphere that was unintentionally introduced to King George Island in the maritime Antarctic South Shetland Islands around 15 years ago, since when it has been reported within or in the vicinity of several research stations. It is not explicitly confirmed that T. maculipennis has established in the natural environment, but life-history characteristics make this likely, thereby making potential eradication or control a challenge. Antarctic Treaty Parties active in the region are developing a coordinated and expanding international response to monitor and control T. maculipennis within and around stations in the affected area. However, there remains no overarching non-native invasive species management plan for the island or the wider maritime Antarctic region (which shares similar environmental conditions and habitats to those of King George Island). Here we present some options towards the development of such a plan. We recommend the development of (1) clear mechanisms for the timely coordination of response activities by multiple Parties operating in the vicinity of the introduction location and (2) policy guidance on acceptable levels of environmental impacts resulting from eradication attempts in the natural environment, including the use of pesticides.

Bees (Family Apidae) hold a key role as pollinators in a wide range of angiosperm communities. South America suffered strong modifications during the last decade due to increasing anthropic activities and the expansion of agricultural areas, particularly the boom of soybean. The goal of this research was to know the current diversity of bees in South and Low Littoral regions in Uruguay. Specimens were collected in the seasons 2015–2016 and 2016–2017 on natural meadows, cultivated grasslands, soybean fields, among others flowering communities. Collected specimens were classified following taxonomic keys. Forty-five bee species or taxa were distinguished belonging to the subfamilies Megachilinae (11), Apinae (22), Halictinae (7), Colletinae (2), and Andreninae (3). Most taxa were classified up to genus and 14 to species level. Bee diversity was higher for the South region, with traditional agriculture and rangelands, than that of the Low Littoral region where an increasing agricultural land use took place during the last decade, particularly soybean. In addition, this research aimed to study the presence of native bees and the introduced Apis mellifera (Apinae) in a soybean field at four transects located at 0, 50, 100, and 200 m from the crop border in both seasons. Native bee species were only present at 0 and 50 m, pointing to the relevance of natural edge plant communities for their preservation. This is the first survey on native bee diversity in Uruguay to be regarded as a baseline and the setup of conservation strategies.

Morphometrical data of pronotum, elytra, and total length of adult males and females of a Gratiana spadicea population from southern Uruguay are given. Descriptions and illustrations of aedeagus and spermatheca are provided for the first time. Females were significatively larger than males in total length. The coefficient of variation of the aedeagus measures ranged from 3.7% to 7.7%, and those of the spermatheca from 4.1% to 11.2%. The best value for the coefficient of determination was obtained for the reciprocal regression (1/Y = a + bX) of the total length of the aedeagus versus the length from the apex to the basal region of the median lobe.Key words: Chrysomelidae, Morphometrics, Gratiana, Uruguay. RESUMO Aspectos morfométricos de adultos de Gratiana spadicea (Klug) (Coleoptera, chysolelidae) do sul do UruguaiDados morfométricos do pronoto, do elitra e do comprimento total de machos e fêmeas adultos de uma população do sul do Uruguai são apresentados. A primeira descrição e ilustrações do edeago e da espermateca são fornecidos. Em termos de comprimento total, as fêmeas são significativamente maiores do que os machos. O coeficiente de variação das medidas do edeago variou de 3,7% a 7,7%, e o da espermateca, de 4,1% a 11,2%. O melhor valor para o coeficiente de determinação foi obtido para a regressão recíproca (1/Y = a + bX) do comprimento total do edeago versus o comprimento do apex à região basal do lobo mediano.

Coprophilous beetles represent an abundant and rich group with critical importance in the functioning of terrestrial ecosystems. Most coprophagous beetles have a stenotopic distribution in relation to vegetation types. Because of this, they are usually very sensitive to environmental changes and are considered well suited as bioindicator organisms. The aim of this study was to analyze variations in coprophilous beetle assemblages in natural and anthropogenic habitats. Coprophilous beetle communities were sampled monthly for 1 year using pitfall traps baited with cow dung, in native xeric upland forests, 15-years-old plantations of Pinus elliottii and pastures in Sierra de Minas, Lavalleja, Uruguay. A total of 7,436 beetles were caught and identified to species or morphospecies level. The most abundant families were Aphodiidae, Scarabaeidae, and Staphylinidae. Differences in species richness, abundance, Shannon index, evenness, and dominance were detected between habitats. Abundances of most frequent families were significantly higher in both kinds of forests. Species richness and diversity of Aphodiidae and Staphylinidae were higher in forests, while Scarabaeidae showed the highest richness and diversity in pine plantations. Species composition significantly differed between habitats. Uroxys terminalis Waterhouse and Ataenius perforatus Harold typified the assemblages in native forests and pine plantations and also discriminated both communities because of their differential pattern of abundance between habitats. Typifying species in pastures were Onthophagus hirculus, Ateuchus robustus (Harold), and Ataenius platensis Blanchard. Habitat type had a strong effect on the coprophilous beetle community structure and composition.

Se describe e ilustra la larva de tercer estadio y la pupa de Homonyx chalcea Blanchard, 1850, Rutelinae xilófago y se aportan datos sobre la biología de la larva en el laboratorio.