Ants,Plants and Butterflies as Diversity Indicators: Comparisons between Strata at six Forest Sites in Venezuela

At six different forest sites in Venezuela, we estimated the diversity and abundance of ants and nymphalid butterflies on the ground and in the canopy, and of plants. Statistical analysis using eight different diversity indices for each species group revealed large variations among them. Ground ants appeared to be the most reliable bioindicators, even when only the five most common species are considered. Results showed in addition that ground ant diversity is correlated to that of canopy ants and that vegetational diversity is linked to butterfly diversity but not to that of canopy ants. Ant species diversity in the canopy was always less than that on the ground. We conclude that no simple index or single taxon describes completely complex ecosystems, thus, biodiversity assessments require tools still to be developed.     

A new non-naked species of Ptychostomella (Gastrotricha) from Brazil

A new species of marine Gastrotricha from Brazil is described and discussed. Ptychostomella lamelliphora sp. n. is one of the several new taxa that were found during an extensive survey of the gastrotrich fauna carried out in 2002 and 2003 along the coastline of the State of São Paulo. The new species is unique in that it possesses cuticular ornamentations in the form of plate-like structures (scales) along the lateral borders of the body and two massive clusters of densely packed adhesive tubes on the ventral surface, near the ano-genital opening. Both these features appear to be adaptations to challenge the high energy waters that characterize the species’ microhabitat: the coarse sublittoral sand in the channel between the mainland and the largest island in the State, Ihlabela. Additionally, a key to the described Ptychostomella species of the world is provided.     

Locomotor Activity Patterns in Ilybius fenestratus (Fabricius) (Coleoptera,Dytiscidae) in a Central Norwegian Lake,with Evidence for Breeding-Induced Arrhythmicity

The diel activity of Ilybius fenestratus was studied in Målsj?en, a lake in S?r-Tr?ndelag, Central Norway (63°14'N, 10°26'E), during 1971–1972. Adults and larvae were sampled in activity traps every week during March–October and every 2–3 weeks during November–February. The traps were emptied every 2 hrs during a 24- hr period. The diel locomotor activity of I. fenestratus was clearly nocturnal, except in the second half of July, for the males also in the first half of July, when surprisingly the population showed an arrhythmic activity pattern. The arrhythmicity is connected with the mating and egg-laying period of the species. The larvae were also nocturnal in the autumn, but showed arrhythmicity under the ice during the winter.     

Another arborescent umbellifer: a new species of Steganotaenia from north-east tropical Africa

THULIN, M., 1991. Another arborescent umbellifer: a new species of Steganotaenia from north-east tropica] Africa. The new species Steganotaenia commiphoroides is described from central and southern Somalia, and south-eastern Ethiopia. It differs from the likewise arborescent S. araliacea , widespread in tropical Africa, in, for example, its 3-foliolate or occasionally simple leaves, leaf teeth with shorter aristae, shorter petioles and pedicels, and fruits with a pair of distinctly winged dorsal ridges.     

Naegleria lovaniensis tarasca New Subspecies, and the Purepecha Strain, a Morphological Variant of N. I. lovaniensis, Isolated from Natural Thermal Waters in Mexico

Amoebae were isolated from a natural thermal water source in Michoacaan, Mexico, in September 1986. Two 500-ml samples were taken from pools with water at 45°C and 46°C and concentrated at 2,000 g for 15 min. The sediment was seeded on nonnutritive agar plates and incubated at 42°C. The isolates were axenized in bactocasitone-serum medium. The identification of the isolates was based on their morphology, total protein and isoenzyme patterns by agarose isoelectric focusing, serology, fine structure, agglutination with Concanavalin A, sensitivity to trimethoprim, capacity to kill mice, and their cytopathic effect in Vero cells. The results showed several morphophysiological, biochemical and serological differences between the isolates and the type strain Aq/9/1/ 45D of Naegleria lovaniensis. These remarkable differences provide sufficient evidence to consider one of the isolates a new subspecies, and the other one a morphological variant of N. l. lovaniensis, which can be differentiated from other Naegleriae by their morphology, biochemistry, serology and physiology. The authors propose the name tarasca for the subspecies and purepecha for the morphological variant.     

Biodiversity and conservation of yeasts

In the framework of initiatives, aiming at a better definition of biodiversity in microorganisms and of its role in ecosystem function, the biology of yeasts is revisited with particular emphasis on their ecology and classification. The limited number of different species isolated from, as well as the exceedingly low yeast cell counts in, most natural environments are discussed and possible explanations presented. The impact of the use of molecular taxonomic techniques of classification on the extent of biodiversity within yeasts is also debated, as well as the possible repercussions of more aggressive pre-isolation treatments of samples.