Entomological Studies in Itaúna, Brazil, an Area With Visceral Leishmaniasis Transmission: Fauna Survey, Natural Leishmania Infection, and Molecular Characterization of the Species Circulating in Phlebotomine Sand Flies (Diptera: Psychodidae).

Among neglected tropical diseases, visceral leishmaniasis (VL) shows great relevance in global terms and is a serious public health concern due to the possibility of severe and lethal forms in humans. In this study, we evaluate entomological factors such as diversity and abundance of phlebotomine sand flies (Diptera:Psychodidae) and the Leishmania species circulating in these species in possible association with VL transmission in the Brazilian town Itaúna. The entomological collections were performed during three consecutive nights, always in the third week of each month, within a period of 12 mo. A total of 1,786 sand fly specimens were collected, from which 20% were collected inside houses. The influence of three local climatic variables (temperature, rainfall, relative humidity) on the population sizes of these insects was evaluated. Temperature was the most influential factor, with a significant positive correlation with the local population size of phlebotomine sand flies collected per month. Lutzomyia longipalpis (Lutz & Neiva, 1912) was the predominant species in the study area. Leishmania DNA was detected in nine out of 133 pools of sand fly females, using nested/PCR, which resulted in a minimal natural infection rate of 2.91%. DNA from Leishmania infantum Nicolle, 1908 (Kinetoplastida: Trypanosomatida), was detected in Evandromyia cortelezzii (Bréthes, 1923), Ev. evandroi (Costa, Lima & Antunes, 1936), Ev. lenti (Mangabeira, 1938), and Ev. termitophila (Martins, Falcão & Silva, 1964), besides Lu. longipalpis. Our study indicates favorable conditions for VL spreading in Itaúna due to the presence of Lu. longipalpis and Le. infantum-infected phlebotomine sand flies.

Ecoepidemiological aspects of visceral leishmaniasis in an endemic area in the Steel Valley in Brazil: An ecological approach with spatial analysis.

Leishmaniases are a group of infectious diseases transmitted by phlebotomine sand flies, and their distribution depends on the presence of vectors, parasites, reservoirs and susceptible hosts in the same environment. In the last decades, visceral leishmaniasis (VL) has become urbanized and reached economically important cities in countries within the transmission zone. Our study was conducted in one of those cities-Ipatinga-in the state of Minas Gerais, Brazil, where the first autochthonous case of VL dates back to 2011. Since no data regarding the epidemiological triad of VL (etiological agent/vector/domestic reservoir) were available for this city, we characterized the local entomological fauna, identified the presence of specific Leishmania DNA in the captured phlebotomine sand flies, and assessed the incidence of canine and human VL. For the entomological survey, we set twenty light traps in ten districts of the city with reports of human and canine VL. The insect captures were performed monthly, during one year, starting in March 2015. A total of 1501 specimens of phlebotomine sand flies belonging to 16 distinct species were captured, with predominance (61.9%) of Lutzomyia longipalpis. Leishmania infantum DNA was detected in L. longipalpis and in Evandromyia cortelezzii test samples. A total of 9,136 dogs were examined, 1,355 of which (14.8%) were serologically positive for VL. The cases were georeferenced and the data were plotted in thematic maps, along with human cases of VL registered by the local Department of Health, during the study period. Our results confirm that the VL transmission cycle is active in Ipatinga, with the presence of vectors carrying Leishmania DNA, canine and human cases of the disease. Spatial analysis allowed for the observation of a positive relationship between canine and human cases of VL and the identification of areas with high priority for control actions in the city. The mapping of high-risk areas, together with an epidemiological study in urban areas, is fundamental to improve the efficacy of the Program for Surveillance and Control of VL (PSCVL) in Brazil.

[Trap-nests used by Centris (Heterocentris) terminata Smith (Hymenoptera: Apidae, Centridini) at secondary Atlantic Forest fragments, in Salvador, Bahia State]. / Ninhos de Centris (Heterocentris) terminata Smith (Hymenoptera: Apidae, Centridini) em fragmentos de Mata Atlântica secundária, Salvador, BA.

Ninety-five nests of Centris (Heterocentris) terminata Smith were collected in trap-nests, during November/2001 and January/2003, at two fragments (PZGV e CFO-UFBA) of secondary Atlantic Forest, in Salvador, Bahia State (13 degrees 01' W e 38 degrees 30' S). The highest nest frequencies occurred from December to February (summer), with no nests foundations from August to October (winter - early spring). Two-hundred eight adults emerged from 347 brood cells, being 164 males and 116 females (1: 0.42). During the study period sex ratio was male biased (chi2 = 9.342; gl = 10; P < 0.05). C. terminata nested in holes with diameters 6, 8, 10 mm, but 84,2% were constructed in 8 and 10 mm. nests had one to seven cells arranged in a linear series with the cells partitions built with a mixture of sand and resin or oil. Male is significantly smaller than female, which emerges from the first cells constructed. Immature mortality occurred in 14.1% of brood cells (n = 49), of which 13.0% were due fail in development and 1.2% due to parasitism of Coelioxys sp. (Hymenoptera: Megachilidae) e Tetraonyx sp. (Coleoptera: Meloidae). In the study site, weather, mainly pluviosity, rather than natural enemies influenced seasonal population abundance. The long period of nesting activity, local abundance and usage of trap nests, suggest the potential of C. terminata for management aiming at pollination of native and cultivated plants.

Ninhos de Centris (Heterocentris) terminata Smith (Hymenoptera: Apidae, Centridini) em fragmentos de Mata Atlântica secundária, Salvador, BA / Trap-nests used by Centris (Heterocentris) terminata Smith (Hymenoptera: Apidae, Centridini) at secondary Atlantic Forest fragments, in Salvador, Bahia State

Foram analisados 95 ninhos de Centris (Heterocentris) terminata Smith, fundados em ninhos-armadilha, entre novembro de 2001 e janeiro de 2003, em dois fragmentos urbanos (CFO-UFBA e PZGV) de Mata Atlântica secundária, em Salvador, BA (13º01Æ W e 38º30Æ S). O maior número de nidificações ocorreu de dezembro a fevereiro (verão), não havendo ninhos fundados nos meses de agosto, setembro e outubro (inverno-primavera). Emergiram 280 adultos de C. terminata (n = 347 células), sendo 164 machos e 116 fêmeas, resultando em razão sexual de 1: 0,42. Durante esse período, a emergência de machos foi significativamente superior a de fêmeas (c2 = 9,342; gl =10; P < 0,05). Os ninhos foram fundados em ninhos-armadilha de madeira com 6, 8, 10 mm de diâmetro, sendo que 84,2 por cento deles foram construídos com 8 e 10 mm. Cada ninhos possui de uma a sete células, dispostas em série em série linear e partições construídas com uma mistura de areia e resina ou óleo. O macho é significativamente menor que a fêmea, sendo que esta última emerge a partir das primeiras células construídas. A mortalidade de imaturos foi baixa, ocorrendo em 14,1 por cento das células (n= 49), sendo 13,0 por cento por falhas no desenvolvimento e 1,2 por cento por parasitas Coelioxys sp. (Hymenoptera: Megachilidae) e Tetraonyx sp. (Coleoptera: Meloidae). Na área estudada, fatores meteorológicos, especialmente a pluviosidade, mostraram-se mais determinantes da abundância temporal do que inimigos naturais. O longo período de atividade anual, abundância local e adequação aos ninhos-armadilha sugerem bom potencial de C. terminata para manejo visando a polinização de plantas nativas e cultivadas.

Ninety-five nests of Centris (Heterocentris) terminata Smith were collected in trap-nests, during November/2001 and January/2003, at two fragments (PZGV e CFO-UFBA) of secondary Atlantic Forest, in Salvador, Bahia State (13º01Æ W e 38º30Æ S). The highest nest frequencies occurred from December to February (summer), with no nests foundations from August to October (winter - early spring). Two-hundred eight adults emerged from 347 brood cells, being 164 males and 116 females (1: 0.42). During the study period sex ratio was male biased (c2 = 9.342; gl = 10; P < 0.05). C. terminata nested in holes with diameters 6, 8, 10 mm, but 84,2 percent were constructed in 8 and 10 mm. nests had one to seven cells arranged in a linear series with the cellÆs partitions built with a mixture of sand and resin or oil. Male is significantly smaller than female, which emerges from the first cells constructed. Immature mortality occurred in 14.1 percent of brood cells (n = 49), of which 13.0 percent were due fail in development and 1.2 percent due to parasitism of Coelioxys sp. (Hymenoptera: Megachilidae) e Tetraonyx sp. (Coleoptera: Meloidae). In the study site, weather, mainly pluviosity, rather than natural enemies influenced seasonal population abundance. The long period of nesting activity, local abundance and usage of trap nests, suggest the potential of C. terminata for management aiming at pollination of native and cultivated plants.

Distribuição de Ninhos de Abelhas Xylocopa (Hymenoptera: Apidae) em uma Area de Dunas Litorâneas / Distribution of Xylocopa (Hymenoptera: Apidae) Nests in a Sea Coastal Sand Dune

The spatial distribution, density and the types of the substrates used by Xylocopa (Megaxylocopa) frontalis Olivier, X. (Schoenherria) subcyanea Pérez and X. (Neoxylocopa) cearensis Ducke, in a sea coastal sand dune, in Bahia, Brazil, were determined. Both the substrate available and those effectively used by the bees for nesting have a clumped spatial distribution. The distribution of the nesting sites could be related to the clumped spatial distribution of the available substrates. The highest occurrence of nests was found of a living individual of Agaristha revoluta (Spr.) DC, which was the substrate predominantly available. The density of available substrates and the density of nesting sites were 12.4/ha and 4.4/ha, respectively.

A distribuição espacial, densidade, e tipos de substratos utilizados por Xylocopa (Megaxylocopa) frontalis Olivier, X. (Schoenherria) subcyanea Pérez e X. (Neoxylocopa) cearensis Ducke, foram determinados em uma área de dunas litorâneas, em Salvador, Bahia. Os substratos encontrados com ninhos e os disponíveis apresentaram distribuição agregada. A distribuição dos substratos com ninhos de Xylocopa está relacionada à distribuição agregada dos substratos disponíveis. As maiores freqüências de ninhos foram observadas em galhos secos e em madeira viva de Agaristha revoluta (Spr.) DC, que são os substratos disponíveis predominantes. A densidade de substratos disponíveis e de substratos com ninhos foram, respectivamente, 12,4/ha e 4,4/ha.

Biologia e Arquitetura de Ninhos de Centris (Hemisiella) tarsata Smith (Hymenoptera: Apidae: Centridini) / Biology and Architecture of Centris (Hemisiella) tarsata Smith (Hymenoptera: Apidae: Centridini) Nests

Centris (Hemisiella) tarsata Smith is an indigenous solitary bee multivoltine widespread on Neotropical region. The aim of this study was to analyse aspects of its biology and structure of nests were investigated using traps nests made by wood, which were randomly distributed in a coastal sand dune environment, in Bahia, Brazil ( 12° 56' S e 38° 21' W). Nests were found in trap nests of 0.8 and 1.0 cm in diameter, but the latter was mostly used by females (68.7 percent). The bees constructed their nests with sand mixed with a substance, probably wax or oil. Completed nests had six to eight cells separated by a space filled with those mixture. From the 16 nests obtained, 55 males and 49 females emerged (sex ratio = 1: 0.89). The innermost cells of the nests produced females and the outermost cells males. Females were significantly (t = 1.679; P < 0.05) larger (x = 4.52 ± 0.11 mm) than males ( x = 3.94 ± 0.13 mm), and no dimorphism in males was found. In general the structural aspects of the nests presented in this work agree with the data found to the same species from others ecosystems.

Centris (Hemisiella) tarsata Smith é uma espécie nativa de abelha solitária, multivoltina com ampla distribuição na região Neotropical. Visando ampliar o conhecimento sobre os hábitos de nidificação dessa espécie, aspectos da biologia e da arquitetura de seus ninhos foram investigados em um fragmento de dunas litorâneas, em Salvador, Bahia, (12° 56' S e 38° 21' W), utilizando-se ninhos-armadilha, confeccionados em madeira, distribuídos ao acaso. Nidificações ocorreram em ninhos-armadilha de 0,8 e 1,0 cm de diâmetro, sendo que este último foi o mais utilizado pelas abelhas (68,75 por cento). Cada ninho possuía de seis a oito células construídas com uma mistura de areia e uma substância aglutinante, provavelmente resina ou óleo. Foram obtidos 16 ninhos, dos quais emergiram 55 machos e 49 fêmeas (razão sexual = 1: 0,89). As fêmeas são produzidas nas primeiras células construídas e os machos nas últimas. O tamanho de machos ( x = 3,94 ± 0,13 mm) e fêmeas (x = 4,52 ± 0,11 mm) diferem significativamente (t = 1,679; P < 0,05), sendo os machos menores do que as fêmeas. De modo geral os aspectos estruturais dos ninhos investigados nesse trabalho assemelham-se àqueles obtidos em estudos realizados com essa espécie em outros ecossistemas.

Diversidade e sazonalidade de abelhas solitárias (Hymenoptera: Apoidea) em dunas litorâneas no nordeste do Brasil / Solitary bees (Hymenoptera: Apoidea) in tropical sand dune: diversity and phyenology

The community structure of cavities-nesting solitary bees species was systematically investigated over two years, from May/97 to April/99, in a fragment of tropical sand dune, Salvador, Bahia (12°56'S; 38°21'W), Northeast of Brazil. Trap nests were placed randomly in the area, in blocks with 16 nests, with variable diameter at a height of 1.5 m. Traps were inspected each 15 days. Seven bee species established 62 nests. Two species were predominant in the area, Centris (Hemisiella) tarsata Smith (58% of the total of established nests) followed by Euplusia musitans Fabricius (31%). In general, bees' abundance showed seasonal fluctuations. The total frequencies of nesting varied between the two years of sampling. The two predominant species presented different seasonal patterns. There were always trap nests available in the field for the bees. Just 14% of the available nests were occupied.

A estrutura da comunidade das espécies de abelhas que nidificam em cavidades pré-existentes foi sistematicamente investigada por um período de dois anos (maio/97 a abril/99), em um fragmento de dunas litorâneas na Area de Proteção Ambiental das Lagoas e Dunas de Abaeté, Salvador, Bahia (12°56'S; 38°21'W). A técnica de amostragem utilizada foi a de ninhos-armadilha, distribuídos no campo ao acaso, em blocos com 16 ninhos, com diâmetros variáveis, à altura de 1,5 m do solo. Os ninhos eram inspecionados quinzenalmente. Foram fundados 62 ninhos pertencentes a sete espécies de abelhas. Duas espécies predominaram na área, Centris (Hemisiella) tarsata Smith (58% do total de ninhos fundados), seguida por Euplusia musitans Fabricius (315). Em geral, houve flutuação sazonal nas abundâncias de abelhas e variação nas freqüências totais de nidificação entre os dois anos de amostragem. As duas espécies predominantes apresentaram diferentes padrões sazonais. Houve sempre ninhos-armadilha disponíveis no campo para as abelhas, que usaram apenas 14% do total oferecido.