Antonio G Valdecasas

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Exceptionally well-preserved giant spermatozoa observed between abundant decalcified carapace valves of ostracods (Crustacea: Ostracoda) were found in Late Glacial to Holocene (14,400 to 10,000 cal years bp) lacustrine sediments in the southern Romanian Carpathians. Analysis by scanning electron microscopy and laser scanning confocal microscopy revealed(More)
The water boatman Trichocorixa verticalis verticalis (Fieber 1851) is originally from North America and has been introduced into the southern Iberian Peninsula, where it has become the dominant Corixidae species in saline wetlands. The reasons for its success in saline habitats, and low abundance in low salinity habitats, are poorly known. Here we explore(More)
Microscopes offer a limited depth of focus which precludes the observation of a complete image of a three-dimensional (3D) object in a single view. Investigations, by a variety of researchers, have led to the development of extended depth of focus algorithms for serial optical slices of microscopic 3D objects in recent years. However, to date, no(More)
Animal and human anatomy is among the most complex systems known, and suitable teaching methods have been of great importance in the progress of knowledge. Examining the human body is part of the process by which medical students come to understand living forms. However, the need to preserve cadavers has led to the development of various techniques to(More)
Recent commentary by Costello and collaborators on the current state of the global taxonomic enterprise attempts to demonstrate that taxonomy is not in decline as feared by taxonomists, but rather is increasing by virtue of the rate at which new species are formally named. Having supported their views with data that clearly indicate as much, Costello et al.(More)
Syncarida are malacostracan crustaceans that live exclusively in fresh and brackish waters all over the world. With the exception of a few Anaspidacea that live in free freshwater (streams, ponds, superficial lakes and caves) the great majority inhabit the interstitial groundwater (they are stygobiont that live in groundwater in the wide sense). The(More)
Biodiversity studies and conservation measures depend on good and up-to-date taxonomic data. General faunistic lists are the result of long periods of sampling. How many species on a global list are actually living in an area can only be answered by updating inventories. The progressive disappearance of taxonomic specialists and the undervaluation of their(More)
It has been stated that small organisms do not have barriers for distribution and will not show biogeographic discreteness. General models for size-mediated biogeographies establish a transition region between ubiquitous dispersal and restricted biogeography at about 1–10 mm. We tested patterns of distribution versus size with water mites, a group of(More)