ABSTRACT
Abstract Melanoides tuberculata is a freshwater gastropod native to Africa and Asia, and currently presents distributed worldwide. The first record of Melanoides tuberculata in South America occurred in Brazil, in the city of Santos, state of São Paulo, in 1967. Therefore, the objective of the present study is to report the occurrence of Melanoides tuberculata for Banana Lagoon and to characterize the current population situation. The gastropods were collected through direct visualization of shells, morphometric measurements of Melanoides tuberculata shells were determined using a digital caliper. After identifying the gastropod and its first distribution in the area, a preliminary descriptive analysis of the population was carried out. The gastropods were classified by grouping the individuals into four classes according to the shell width (mm). This is the first record of the occurrence of Melanoides tuberculata, in Banana Lagoon, Caucaia municipality, Ceará state, Northeast Brazil, being the largest specimen cited in the literature (33.77 mm) and 92.65% of the gastropods present in sizes above the first reproduction stages.
Resumo Melanoides tuberculata é um gastrópode de água doce nativo da África e da Ásia e atualmente apresenta-se distribuído mundialmente. O primeiro registro de Melanoides tuberculata na América do Sul ocorreu no Brasil, na cidade de Santos, estado de São Paulo, em 1967. Portanto, o objetivo do presente estudo é relatar a ocorrência de Melanoides tuberculata para Lagoa do Banana, caracterizando a situação atual da população no local. Os gastrópodes foram coletados através da visualização direta de conchas, e as medidas morfométricas das conchas de Melanoides tuberculata foram determinadas por meio de um paquímetro digital. Após identificar o gastrópode e constando sua primeira distribuição na área, realizou-se uma análise preliminar descritiva da população. Os gastrópodes foram classificados agrupando os indivíduos em quatro classes de acordo com a largura da concha (mm). Este é o primeiro registro da ocorrência de Melanoides tuberculata, na Lagoa da Banana, município de Caucaia, estado do Ceará, Nordeste do Brasil, sendo o maior exemplar citado na literatura (33,77 mm) já registrado e 92,65% dos gastrópodes apresentam-se em tamanhos acima do primeiro estágios de reprodução.
Subject(s)
Humans , Animals , Gastropoda , Snails , Brazil , Fresh WaterABSTRACT
Abstract Melanoides tuberculata is a freshwater gastropod native to Africa and Asia, and currently presents distributed worldwide. The first record of Melanoides tuberculata in South America occurred in Brazil, in the city of Santos, state of São Paulo, in 1967. Therefore, the objective of the present study is to report the occurrence of Melanoides tuberculata for Banana Lagoon and to characterize the current population situation. The gastropods were collected through direct visualization of shells, morphometric measurements of Melanoides tuberculata shells were determined using a digital caliper. After identifying the gastropod and its first distribution in the area, a preliminary descriptive analysis of the population was carried out. The gastropods were classified by grouping the individuals into four classes according to the shell width (mm). This is the first record of the occurrence of Melanoides tuberculata, in Banana Lagoon, Caucaia municipality, Ceará state, Northeast Brazil, being the largest specimen cited in the literature (33.77 mm) and 92.65% of the gastropods present in sizes above the first reproduction stages.
Resumo Melanoides tuberculata é um gastrópode de água doce nativo da África e da Ásia e atualmente apresenta-se distribuído mundialmente. O primeiro registro de Melanoides tuberculata na América do Sul ocorreu no Brasil, na cidade de Santos, estado de São Paulo, em 1967. Portanto, o objetivo do presente estudo é relatar a ocorrência de Melanoides tuberculata para Lagoa do Banana, caracterizando a situação atual da população no local. Os gastrópodes foram coletados através da visualização direta de conchas, e as medidas morfométricas das conchas de Melanoides tuberculata foram determinadas por meio de um paquímetro digital. Após identificar o gastrópode e constando sua primeira distribuição na área, realizou-se uma análise preliminar descritiva da população. Os gastrópodes foram classificados agrupando os indivíduos em quatro classes de acordo com a largura da concha (mm). Este é o primeiro registro da ocorrência de Melanoides tuberculata, na Lagoa da Banana, município de Caucaia, estado do Ceará, Nordeste do Brasil, sendo o maior exemplar citado na literatura (33,77 mm) já registrado e 92,65% dos gastrópodes apresentam-se em tamanhos acima do primeiro estágios de reprodução.
ABSTRACT
Diploid males have long been considered a curiosity contradictory to the haplo-diploid mode of sex determination in the Hymenoptera. In Apis mellifera, 'false' diploid male larvae are eliminated by worker cannibalism immediately after hatching. A 'cannibalism substance' produced by diploid drone larvae to induce worker-assisted suicide has been hypothesized, but it has never been detected. Diploid drones are only removed some hours after hatching. Older larvae are evidently not regarded as 'false males' and instead are regularly nursed by the brood-attending worker bees. As the pheromonal cues presumably are located on the surface of newly hatched bee larvae, we extracted the cuticular secretions and analyzed their chemical composition by gas chromatograph-mass spectrometry (GC-MS) analyses. Larvae were sexed and then reared in vitro for up to three days. The GC-MS pattern that was obtained, with alkanes as the major compounds, was compared between diploid and haploid drone larvae. We also examined some physical parameters of adult drones. There was no difference between diploid and haploid males in their weight at the day of emergence. The diploid adult drones had fewer wing hooks and smaller testes. The sperm DNA content was 0.30 and 0.15 pg per nucleus, giving an exact 2:1 ratio for the gametocytes of diploid and haploid drones, respectively. Vitellogenin was found in the hemolymph of both types of imaginal drones at 5 to 6 days, with a significantly lower titer in the diploids.