Systematics and distribution of the genus Johnsonius Marsh (Hymenoptera, Braconidae, Doryctinae) with description of two new species from Brazil

The genus Johnsonius Marsh includes five species, most of them known from Costa Rica and one known from Venezuela, Peru and Costa Rica. Two of these species and two new species were recently collected in Atlantic rain forest. Description of the new species, illustrations of some morphological characters, a key for identification of all known species and the new geographic records are presented.

Antifungal susceptibility and distribution of Candida spp. isolates from the University Hospital in the municipality of Dourados, State of Mato Grosso do Sul, Brazil

Introduction Hospital infections caused by Candida spp. are a leading cause of morbidity and mortality in hospitalized patients, particularly those that are critically ill or immunocompromised. In this study, the distribution of Candida species in isolates from the University Hospital of the Federal University at Grande Dourados and their in vitro susceptibility to antifungal drugs were analyzed. Methods Yeasts were phenotypically identified using classical methodologies. Antifungal susceptibility tests to amphotericin B and fluconazole were performed using the broth microdilution technique. Results A total of 50 Candida isolates were obtained from hospitalized patients during the study period. We analyzed yeast isolates from urine (n=31; 62%), blood (n=12; 24%), and tracheal secretions (n=7; 14%). The following Candida species were identified: C. tropicalis (n=21; 42%), C. albicans (n=18; 36%), C. glabrata (n=10; 20%), and C. krusei (n=1; 2%). Antifungal susceptibility tests demonstrated that C. albicans was susceptible to both antifungal agents. However, 31.2% of the non-C. albicans Candida isolates displayed dose-dependent susceptibility to fluconazole, and 3.1% were resistant to amphotericin B. Conclusions In contrast to previous reports, our results indicated that C. tropicalis was the most commonly isolated yeast species among the hospital patients. The predominance of non-C. albicans Candida infections confirms the importance of species-level identification for implementing appropriate antifungal therapies.

Density, size and distribution of stomata in 35 rainforest tree species in Central Amazonia

Stomata are turgor-operated valves that control water loss and CO2 uptake during photosynthesis, and thereby water relation and plant biomass accumulation is closely related to stomatal functioning. The aims of this work were to document how stomata are distributed on the leaf surface and to determine if there is any significant variation in stomatal characteristics among Amazonian tree species, and finally to study the relationship between stomatal density (S D) and tree height. Thirty five trees (>17 m tall) of different species were selected. Stomatal type, density (S D), size (S S) and stomatal distribution on the leaf surface were determined using nail polish imprints taken from both leaf surfaces. Irrespective of tree species, stomata were located only on the abaxial surface (hypostomaty), with large variation in both S D and S S among species. S D ranged from 110 mm-2 in Neea altissima to 846 mm-2 in Qualea acuminata. However, in most species S D ranges between 271 and 543 mm-2, with a negative relationship between S D and S S. We also found a positive relationship between S D and tree height (r² = 0.14, p < 0.01), but no correlation was found between S D and leaf thickness. The most common stomatal type was anomocytic (37%), followed by paracytic (26%) and anisocytic (11%). We conclude that in Amazonian tree species, stomatal distribution on the leaf surface is a response most likely dependent on the genetic background of every species, rather than a reaction to environmental changes, and that somehow S D is influenced by environmental factors dependent on tree height.

Structure and distribution of glandular trichomes in three species of Bignoniaceae

Glandular trichomes play a major role in the morphological characterization of the Bignoniaceae. Due to their great diversity of forms and functions, this study aimed to inventory the glandular trichomes present in the aerial vegetative axis of Amphilophium magnoliifolium, Martinella obovata and Stizophyllum riparium, analyze their structure and register the participation of ants in these plants. Fresh samples from the nodal region, petiole and from medium to apical regions of the leaflet blade were fixed and processed according to usual methods in light and scanning electron microscopies. The glandular trichomes found were: peltate, capitate, stipitate, and patelliform/cupular. Peltate trichomes are the most abundant ones and present the most uniform distribution. Patelliform/cupular trichomes occur at specific regions, such as prophylls, leaflet blade and nodal regions. Martinella obovata is the only species that presents capitate and stipitate trichomes, which are widely distributed along the entire aerial vegetative axis. Ants were found in all species, mainly at nodal regions. The occurrence of the capitate-type trichome is reported for the first time to the genus.

Sewage impact on the composition and distribution of Polychaeta associated to intertidal mussel beds of the Mar del Plata rocky shore, Argentina

The polychaete composition and distribution within mussel beds were studied in order to assess organic pollution due to domestic sewage in a rocky shore of Mar del Plata (Argentina) during 1997. Four stations and a control site were randomly sampled around the local effluent. Quantitative data on polychaetes, as well as sediment accumulated among mussels and its organic carbon content were measured. Polychaete distribution patterns are related to the organic matter gradient, being Capitella cf. capitata, Neanthes succinea (Frey & Leuckart, 1847) and Boccardia polybranchia (Haswell, 1885) the dominant indicator species close to the effluent. At medial distances, the cirratulids Caulleriella alata (Southern, 1914) and Cirratulus cirratus (Müller, 1776) are very important in abundance. The syllids Syllis prolixa Ehlers, 1901 and S. gracilis Grube, 1840 are distributed along the study area, but dominate at the medial stations and at the control site. The orbiniid Protoariciella uncinata Hartmann-Schröder, 1962 is subdominant at the control station.

Biosyslematics and distribution of Simuliid vectors of human onchocerciasis in South America

A brief review is given of the taxonomic status, biology and medical importance, and distribution of the vectors of human onchocerciasis in Latin America. Key reference works are cited and distribution maps of each vector species in relation to the known onchocerciasis foci are given.

Taxonomy and distribution of phlebotomine sandflies in Venezuela: I. The Oswaldoi species group of the genus Lutzomyia (Diptera: Psychodidae)

Species of sandflies in the oswaldoi-group of the genus Lutzomyia occuring in Venezuela are reviewed. A new species, Lutzomyia saccai n. sp. is described. A distribution map and pictorial keys for males and females are provided with notes on biological and ecological data collected in Venezuela.

Taxonomy and distribution of phlebotomine sandflies in Venezuela: II. The subgenus Trichopygomyia of the genus Lutzomyia (Diptera: Psychodidae)

Species of sandflies in the subgenuys Trichopygomyia of the genus Lutzomyia occurring in Venezuela are reviewd. A new species, Lutzomyia pinna n. sp. is described. A distribution map and a pictorial key for maleds are provided with remarks on the ecological data collected in Venezuela.

Digenea and acanthocephala of elasmobranch fishes from the southern coast of Brazil

New records for helminth species recovered from elasmobranch fishes in Brazil are established. Digenean and acanthocephalan parasites of elasmobranch fishes are reported from the southern coast of Brazil: Otodistomum veliporum (Creplin, 1837) Stafford, 1904 (Digenea: Azygiidae) in the stomach and spiral valve of Dipturus trachydermus and in the spiral valve of Squatina sp. Cystacanths and juveniles of the acanthocephalans Corynosoma australe Johnston, 1937 and Corynosoma sp., in the spiral valve of Squatina sp., Galeorhinus galeus and Hexanchus griseus and in the stomach of Squalus megalops; a juvenile of Gorgorhynchus sp., in the spiral valve of Sphyrna zygaena. Dipturus trachydermus and Squatina sp. are new host records for O. veliporum. Digeneans and acanthocephalans are reported for the first time parasitizing elasmobranch fishes in Brazil.

Diversity and distribution of sandflies (Diptera: Psychodidae: Phlebotominae) in a military area in the state of Amazonas, Brazil

This study reports the distribution, ecotopes and fauna diversity of sandflies captured in five training bases on a military reserve in Manaus, state of Amazonas (AM). A total of 10,762 specimens were collected, which were distributed among 58 species, with the highest number recorded at Base Instruction 1 (BI1). A higher rate of species richness was found at the Base Instruction Boina Rajada and low levels of diversity associated with a high abundance index with the clear dominance of Lutzomyia umbratilis, Lutzomyia ruii and Lutzomyia anduzei were found at BI1. The abundance of Lu. umbratilis raises the possibility of outbreaks of American cutaneous leishmaniasis by the main vector of the disease in AM.

Density and distribution of nests of Mycetophylax simplex (Emery) (Hymenoptera, Formicidae) in areas with mobile dunes on the northern coast of Rio Grande do Sul, Brazil

Studies on lower attines are scarce, especially on nesting and foraging ecology and behavior. This study aimed to contribute to the knowledge of an Attini in dunes ecosystems through the description of density and spatial distribution of Mycetophylax simplex (Emery, 1887) nests in a strip of mobile dunes in the Praia Grande beach, Torres, northern coast of Rio Grande do Sul, Brazil. The density and spatial distribution of nests were estimated in four plots of 2,500 m² each, in which were found 20, 209, 284 and 324 nests, with average densities of 0.01 nests/m², 0.09, 0.11 and 0.13 nests/m², respectively. The nests were found near to the vegetation and showed clumped distribution. The density and distribution pattern of the nests seem to be related to the availability of nesting places and foraging resources.

Observations on the biology and distribution of Uresiphita reversalis (Lepidoptera, Crambidae), a defoliator of the native tree Calia secundiflora in México

Observations on the biology and distribution of Uresiphita reversalis (Lepidoptera, Crambidae), a defoliator of the native tree Calia secundiflora in México. Uresiphita reversalis (Guenée, 1854) feeding on Calia secundiflora (Ortega) Yakovlev is recorded for the first time in the state of Hidalgo, Mexico. New aspects regarding the life cycle, feeding behaviour, geographical distribution and host plant damage by U. reversalis on C. secundiflora are here presented and discussed.

Expression and distribution of connexin 32 in rat liver with experimentally induced fibrosis

The connexin 32 (Cx32) is a protein that forms the channels that promote the gap junction intercellular communication (GJIC) in the liver, allowing the diffusion of small molecules through cytosol from cell-to-cell. Hepatic fibrosis is characterized by a disruption of normal tissue architeture by cellular lesions, and may alter the GJIC. This work aimed to study the expression and distribution of Cx32 in liver fibrosis induced by the oral administration of dimethylnitrosamine in female Wistar rats. The necropsy of the rats was carried out after five weeks of drug administration. They presented a hepatic fibrosis state. Sections from livers with fibrosis and from control livers were submitted to immunohistochemical, Real Time-PCR and Western-Blot analysis to Cx32. In fibrotic livers the Cxs were diffusely scattered in the cytoplasm, contrasting with the control livers, where the Cx32 formed junction plaques at the cell membrane. Also it was found a decrease in the gene expression of Cx32 without reduction in the protein quantity when compared with controls. These results suggest that there the mechanism of intercellular communication between hepatocytes was reduced by the fibrotic process, which may predispose to the occurrence of a neoplastic process, taken in account that connexins are considered tumor suppressing genes.

A field survey of crop management practices and distribution of ALS resistant Euphorbia heterophylla in two states in southern Brazil

Herbicide resistance was reported in Brazil almost ten years ago. One of the main weeds with herbicide resistance is wild poinsettia (Euphorbia heterophylla). This work evaluates the distribution of ALS-resistant E. heterophylla in two states in southern Brazil and determines the major contributing management causes for weed resistance selection in the area. E. heterophylla seeds from 148 sites located in Paraná and Rio Grande do Sul were sampled during 2001 and 2002. Farmers provided specific site data for weed control, tillage system, crop rotation and harvesting operations during previous years. ALS resistant E. heterophylla biotypes were found widely distributed in the survey area. Data analysis suggests seed dissemination is unlikely to explain the widespread distribution of resistance. The most probable factor for the selection of the resistant E. heterophylla is the persistent high use of ALS-inhibiting herbicides over time. Indirect evidence is presented demonstrating the need to educate legislators and farmers about the importance of herbicide mixtures as a strategy to prevent herbicide resistance.

Effect of period of sugarcane cultivation on the abundance and distribution of weed seeds in the soil profile

An experiment was laid down in a screen house to determine the distribution of weed seeds at different soil depths and periods of cultivation of sugarcane in Ilorin, Nigeria. Soil samples from different depth levels (0-10 cm, 11-20 cm and 21-30 cm) were collected after harvesting of canes from three different land use fields (continuous sugarcane cultivation for > 20 years, continuous sugarcane cultivation for < 10 years after long fallow period and continuous sugarcane cultivation for < 5 years after long fallow period) in November, 2012. One kilogram of the sieved composite soil samples was arranged in the screen house and watered at alternate days. Germinating weed seedlings were identified, counted and then pulled out for the period of 8 months. Land use and soil depth had a highly significant (p £ 0.05) effect on the total number of weeds that emerged from the soil samples. The 010 cm of the soil depth had the highest weed seedlings that emerged. There was an equal weed seed distribution at the 11-20 cm and 21-30 cm depths of the soil. Sugarcane fields which have been continuously cultivated for a long period of time with highly disturbing soil tillage practices tend to have larger seed banks in deeper soil layers (11-20 cm and 21-30 cm) while recently opened fields had significantly larger seed banks at the 0-10 cm soil sampling depth.