Dynamics of Tree Diversity in Undisturbed and Logged Subtropical Rainforest in Australia

In subtropical rainforest in eastern Australia, changes in the diversity of trees were compared under natural conditions and eight silvicultural regimes over 35 years. In the treated plots basal area remaining after logging ranged from 12 to 58 m^{2}/ha. In three control plots richness differed little over this period. In the eight treated plots richness per plot generally declined after intervention and then gradually increased to greater than original diversity. After logging there was a reduction in richness per plot and an increase in species richness per stem in all but the lightest selective treatments. The change in species diversity was related to the intensity of the logging, however the time taken for species richness to return to pre-logging levels was similar in all silvicultural treatments and was not effected by the intensity of treatment. These results suggest that light selective logging in these forests mainly affects dominant species. The return to high diversity after only a short time under all silvicultural regimes suggests that sustainability and the manipulation of species composition for desired management outcomes is possible.     

Paranosema locustae (Microsporidia) in grasshoppers (Orthoptera: Acridoidea) of Argentina: field host range expanded

Detection of Paranosema locustae in three grasshopper species (Ronderosia bergi, Sinipta dalmani, Trimerotropis pallidipenis) within the establishment area of the Pampas expands the field host range of the pathogen to 20 species in the country. The newly recorded hosts might be important in the persistence and dispersal of the pathogen.     

Rainforest habitat resistance to the migration of Phytoseiulus persimilis Athias-Henriot (Acari: Phytoseiidae) in south-eastern Queensland

Abstract  This paper tests the hypothesis that habitat differences affect the migratory ability of the Chilean predatory mite, Phytoseiulus persimilis , an introduced biological control agent of the spider mite, Tetranychus urticae . It is suggested that habitat resistance accounts for the species' inability to invade rainforests in south-eastern Queensland, Australia. Like its prey, P. persimilis migrates to distant plants on air currents. To test our hypothesis, populations of the Chilean predatory mite were established on potted bean plants in both remnant rainforest and adjacent open fields, and their migration monitored using sticky traps. Overall it was found that prey populations on leaves were similar in both habitats, but those of predators were about 20% lower in rainforest. However, the numbers of both predators and prey caught on sticky traps in rainforest were about 6% and 25%, respectively, of those caught in open fields, indicating a strongly reduced rate of aerial migration in the forest. The number of P. persimilis caught on the sticky traps increased with increasing populations of predators on foliage. Thus, dense vegetation inhibits the movement of air currents and inhibits colonisation by both predators and, to a lesser extent, spider mites. These results suggest that the inhibition of aerial migration is one reason for lower numbers of P. persimilis in forest habitats, both because its own vagility is restricted, and because its prey is less able to disperse.     

A new species of Hyalella (Crustacea,Amphipoda, Dogielinotidae) from the Atlantic Forest of Misiones,Argentina

The freshwater genus Hyalella Smith, 1874 has a distribution restricted to the Western Hemisphere with most species being found in South America. In this report we describe a new species of Hyalella from the Atlantic Forest of the Misiones province, Argentina.     

A new species,Litomosoides odilae n. sp (Nematoda: Onchocercidae) from Oligoryzomys nigripes (Rodentia: Muridae) in the rainforest of Misiones,Argentina

A new species of Litomosoides was collected from the abdominal cavity of Oligoryzomys nigripes (Rodentia: Muridae) in a semideciduous secondary rainforest of Misiones, Argentina. Litomosoides odilae n. sp. belongs to the carinii group and is characterized by the amphids displaced dorsally; buccal capsule with an anterior segment transparent and an annular asymmetrical thickening; esophagus divided, with the posterior glandular portion slightly wider than the muscular; male cloacal aperture strongly protruded; and microfilaria sheathed with an attenuated tail. The morphology of the new species, which is similar to that of L petteri, a parasite of marsupials in Brazil, suggests that host-switching events may have occurred in the diversification of this genus.     

Characterization and prevalence of pigments in the muscle of hawkfish (Cheilodactylus bergi)

Melanin pigment was prevalent in skeletal muscle of 338 out of 1079 Cheilodactylus bergi sampled from the Argentine-Uruguay Common Fisheries Zone. A higher proportion of males than of females was pigmented, and only in males did that proportion increase with body length. No parasites were found in the muscle.     

The Stenopodainae (Hemiptera,Heteroptera) of Argentina

In Argentina, 10 genera and 33 species of Stenopodainae (Hemiptera: Reduviidae) have been recorded. Diagnoses of the genera, subgenera and species are given, and an illustrated key to genera is provided. Six species are new records for Argentina and an additional seven species represent new records for provinces.     

Fusacarus australis sp. n., the first endemic species of Australian Glycyphagidae (Acari)

Abstract  Fusacarus australis sp. n. (Acari: Glycyphagidae) is described from specimens from tree holes and rainforest litter in Lamington National Park, Queensland. This is the first record of Fusacarus Michael from the Southern Hemisphere, and the first Australian native species of Glycyphagidae. A key to the world fauna of Fusacarus is provided.     

The Process of Chamber Formation in the Foraminifer Rosalina floridana (Cushman)

SYNOPSIS. The foraminifer Rosalina floridana builds a chambered, calcareous test which is periodically enlarged by the addition of new chambers. R. floridana begins to form a chamber by constructing an algal growth cyst which covers the dorsal side of the animal and is cemented to the substrate. The pseudopods that build the cyst coalesce to form a cytoplasmic template or anlage on which the chamber walls will be secreted. Electron micrographs reveal the anlage cytoplasm to be a “froth” of nearly empty vesicles which contain mitochondria, fibrillar material, and electron dense granules. The organic lining of the new chamber is secreted on the anlage by pseudopods extending thru it. After the organic lining is completed, cytoplasm from within the test flows into the forming chamber and forces the anlage cytoplasm out thru the new aperture. This “frothy” anlage cytoplasm forms a sheath over the dorsal surface of the test; while it is in place, a layer of calcite is deposited on the walls of the new chamber and over the rest of the test. When calcification is completed, the sheath breaks up and is incorporated into newly formed pseudopods as the foraminifer gradually moves out of the growth cyst and begins normal feeding. The production of vesiculated cytoplasm in normal pseudopods and in the anlage is viewed as a method of greatly increasing cytoplasmic volume with a resultant very small loss in cytoplasmic mass. In the anlage during the production of the organic lining the vesiculated cytoplasm apparently acts only as a support for the membranes being secreted by the pseudopods and presumably does not take part in the secretory process. This same cytoplasm forms the sheath that is present during calcification. The view is advanced that, altho the sheath could be active during calcification with the mitochondria within the vesicles actively transporting calcium to sites of crystal growth, its more probable function is to form a partition between the parts to be calcified and the environment. The foraminifer could then secrete CaCO₃ from pooled reserves in the cytoplasm into the area between the sheath and the chamber membranes. The basal membrane is considered the nucleating agent during calcification and is responsible for the ordering of the crystals so their C axes are perpendicular to the surface of the chamber.     

The effect of environmental parameters on growth,cholinesterase activity and glutathione S-transferase activity in the earthworm (Apporectodea caliginosa)

The effect of age and environmental parameters on growth, cholinesterase (ChE), and glutathione S-transferase (GST) activities were assessed in juvenile Apporectodea caliginosa earthworms. Earthworms were maintained in three types of soil- loam, sandy, and clay- at a range of moisture contents (15-30%), and temperatures (5-20 C). Earthworm age (1-3 months) had no significant affect on ChE activity. Growth rates were influenced by all environmental parameters tested and these effects were interrelated. Optimum conditions for growth appeared to be in loam or sandy soil with 25-30% moisture at 10-15 C. The GST activity was influenced by soil temperature and activity was significantly higher at 15 C than at 5 C and 10 C. Soil type also influenced GST activity and this influence was dependent on moisture content. In sandy soil GST activity was significantly lower at 30% moisture than at lower moisture contents, in loam soil GST activity was significantly higher at 15% moisture than at higher moisture contents, while in clay soil GST activity was not affected by moisture content. These results indicate that in field experiments when evaluating GST activity soil temperature and soil type need to be consistent between control and 'contaminated sites'. ChE activity was only affected by temperature, so this should be considered when comparing control and treatedareas.     

The effect of environmental parameters on growth, cholinesterase activity and glutathione S-transferase activity in the earthworm (Apporectodea caliginosa)

The effect of age and environmental parameters on growth, cholinesterase (ChE), and glutathione S-transferase (GST) activities were assessed in juvenile Apporectodea caliginosa earthworms. Earthworms were maintained in three types of soil- loam, sandy, and clay- at a range of moisture contents (15-30%), and temperatures (5-20 C). Earthworm age (1-3 months) had no significant affect on ChE activity. Growth rates were influenced by all environmental parameters tested and these effects were interrelated. Optimum conditions for growth appeared to be in loam or sandy soil with 25-30% moisture at 10-15 C. The GST activity was influenced by soil temperature and activity was significantly higher at 15 C than at 5 C and 10 C. Soil type also influenced GST activity and this influence was dependent on moisture content. In sandy soil GST activity was significantly lower at 30% moisture than at lower moisture contents, in loam soil GST activity was significantly higher at 15% moisture than at higher moisture contents, while in clay soil GST activity was not affected by moisture content. These results indicate that in field experiments when evaluating GST activity soil temperature and soil type need to be consistent between control and 'contaminated sites'. ChE activity was only affected by temperature, so this should be considered when comparing control and treatedareas.     

Late Quaternary paleoenvironmental reconstruction of the Tremiti structural high (Central Adriatic Sea) from benthic foraminiferal assemblages

Foraminiferal analyses carried out on the VTR01/8 core (Tremiti Islands, Adriatic Sea) lead to the reconstruction of the paleoenvironmental evolution of the area. Although the core site is located at about 1000 km from the Po delta, this study shows that the installation of the recent sedimentological and run-off system (with a shore parallel clay-belt) is similar to that described at sites much closer to the Po delta. The statistical analysis singled out four associations that correspond to four distinct environments. The ecological preferences of the most abundant taxa that characterize each environment reveal that from the bottom of the core to − 50 cm, there is a slight increase of the water depth after which the water depth increases until the present level. Association A (that comprises subclusters A1, A2 and A3) is characterized by shallow-water taxa (e.g., Ammonia beccarii, Quinqueloculina spp. and Elphidium granosum) showing that in the past an infralittoral environment typified the Tremiti High. The subclusters of Association A show that during the deposition of the lower part of the core there had been an alternation of phases characterized by different degrees of riverine influence: the site was at first under the influence of river outflow (A2) that later bypassed the core site (A3) and then came back, although located further away than before (A1). With the rising of the sea level, the Tremiti High became only marginally affected by river influence because the core site is located at a considerable distance from the Po outlets and seaward with respect to the center of the modern mud-belt. As a matter of fact, association B (Bulimina marginata, Cassidulina carinata and Textularia spp.), which starts at − 46 cm, shows the typical characteristics of the modern mud-belt outer-shelf assemblage, although the presence of opportunistic species is limited by the distant position with respect to the Po delta.     

Geographic distribution of the Anostracans (Crustacea) in Argentina (South America)

Using materials of collection from nearly all the Argentinian provinces, a map of the distribution of the anostracans in Argentina has been elaborated. From the eight families recognized on a world scale, four are represented in the country; being the best represented considering the number of the species is the Branchinectidae one. New localities are mentioned for Branchinecta rocaen‐sis, Dendrocephalus cervicornis, D. brasiliensis, Phallocryptus salinicola and Anemia salina.     

Detection of Leishmania infantum in naturally infected Lutzomyia longipalpis (Diptera: Psychodidae: Phlebotominae) and Canis familiaris in Misiones, Argentina: the first report of a PCR-RFLP and sequencing-based confirmation assay

In this study, a genotypification of Leishmania was performed using polimerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and sequencing techniques to identify species of Leishmania parasites in phlebotomine sand flies and dogs naturally infected. Between January-February of 2009, CDC light traps were used to collect insect samples from 13 capture sites in the municipality of Posadas, which is located in the province of Misiones of Argentina. Sand flies identified as Lutzomyia longipalpis were grouped into 28 separate pools for molecular biological analysis. Canine samples were taken from lymph node aspirates of two symptomatic stray animals that had been positively diagnosed with canine visceral leishmaniasis. One vector pool of 10 sand flies (1 out of the 28 pools tested) and both of the canine samples tested positively for Leishmania infantum by PCR and RFLP analysis. PCR products were confirmed by sequencing and showed a maximum identity with L. infantum. Given that infection was detected in one out of the 28 pools and that at least one infected insect was infected, it was possible to infer an infection rate at least of 0.47% for Lu. longipalpis among the analyzed samples. These results contribute to incriminate Lu. longipalpis as the vector of L. infantum in the municipality of Posadas, where cases of the disease in humans and dogs have been reported since 2005.