A new species of the genus Cylindera (Coleoptera: Cicindelidae) from southern Bolivia with imitating behaviour to co-occurring ants.

Cylindera (Cylindera) julietae sp. nov. (Cicindelidae: Cicindelini) is described as new for science from southern Bolivia. The new species is compared to a similar species Cylindera (Cylindera) confluentesignata (W. Horn, 1915). Colour photographs of habitus, habitat and diagnostic characters of the two similar species are presented. The behaviour of adults of the new species, imitating that of co-occurring ants, is discussed.

A new species of the genus Oxycheila (Coleoptera: Cicindelidae) from Bolivia.

The new species Oxycheila alenatiki sp. nov. (Cicindelidae: Megacephalini) is described from central Bolivia and compared to related species. Colour photographs of habitus and male genitalia of O. alenatiki sp.nov. and related species O. gracillima Bates, 1872 and O. oberthueri Horn, 1897 are compared. A modified taxonomic key to the gracillima species group is provided.

The unique functioning of a pre-Columbian Amazonian floodplain fishery.

Archaeology provides few examples of large-scale fisheries at the frontier between catching and farming of fish. We analysed the spatial organization of earthen embankments to infer the functioning of a landscape-level pre-Columbian Amazonian fishery that was based on capture of out-migrating fish after reproduction in seasonal floodplains. Long earthen weirs cross floodplains. We showed that weirs bear successive V-shaped features (termed 'Vs' for the sake of brevity) pointing downstream for outflowing water and that ponds are associated with Vs, the V often forming the pond's downstream wall. How Vs channelled fish into ponds cannot be explained simply by hydraulics, because Vs surprisingly lack fishways, where, in other weirs, traps capture fish borne by current flowing through these gaps. We suggest that when water was still high enough to flow over the weir, out-migrating bottom-hugging fish followed current downstream into Vs. Finding deeper, slower-moving water, they remained. Receding water further concentrated fish in ponds. The pond served as the trap, and this function shaped pond design. Weir-fishing and pond-fishing are both practiced in African floodplains today. In combining the two, this pre-Columbian system appears unique in the world.

Algunos aspectos moleculares de la regulación de la división celular / Moleculars aspects some of the regulation of the cellular division

El presente trabajo intenta mostrar un panorama, a nivel molecular, de los avances logrados en los últimos años en el estudio del proceso de división celular, enfocándose en la regulación del inicio de la división, a través del descubrimiento del gen cdc2-ciclina y su acción fosforilante sobre diversos sustratos relacionados con el desencadenamiento de la división celular

Nueva tinción para fibras del tejido conectivo / Tintion new for tissue conective of fibres

Se presenta una técnica de tinción que combina varios colorantes de rutina y que en conjunto tiñen a las fibras colágenas y elastina propias del tejido conectivo. También tiñe a la fibrina y como un hallazgo, ya que no se esperaba, tiñe fibras musculares esqueléticas. Es una tinción que en una sola ejecución y rápidamente puede teñir varios tipos de proteínas fibrosas de diferentes tipos de tejidos, exhibiéndolos tan nítidamente que permite su reconocimiento y estudio favoreciendo el diagnóstico histológico a nivel del microscopio de luz