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The effect of mating delay on the ovary structure of virgin queens of Melipona quadrifasciata anthidioides (Hymenoptera: Apidae) was investigated. Virgin queens 15, 20, 25 and 30 days old were dissected to analyze their degree of ovary degeneration. To verify whether the degeneration would cause permanent sterility, virgin queens of the same ages (15, 20, 25 and 30 days) were mated and accompanied for at least 14 days to verify whether there was physogastry and then dissected. The ovaries were analyzed by histology, histochemical tests and TUNEL to verify programmed cell death. The results showed that mating delay interrupted oogenesis preventing vitellogenesis. Mating delay results in ovary degeneration which increased with queen age. However, even when there was ovariole degeneration, 25-day-old virgin queens after mating presented normal ovariole activation.

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The interactions of insect societies are associated with chemical signals released by the exocrine glands that control some insect behaviors. Exocrine glands can be classified into different classes: class I release substances that cross the body cuticle and class III glands that have a conducting canal. This study compares the morphology of intramandibular and mandibular glands in virgin queens of different ages, as well as in nurses and forager workers of Melipona scutellaris. We have found the occurrence of two types of glands inside the mandible; glands of class I, corresponding to a well-developed epithelium, secretory only in virgin queens, and glands of class III. On the other hand, mandibular glands have been found to be well-developed in workers and queens and they also have high amounts of mitochondria and smooth endoplasmic reticulum. Together, these data show that the mandibular and intramandibular glands of M. scutellaris virgin queens have morphological features that indicate the synthesis of compounds that are lipid in nature. Furthermore, both glands have a similar developmental degree in newly emerged and 7-day-old ones.

O uso de inseticidas mais tóxicos para uma praga do que a saúde natural pode favorecer o salvamento desses organismos benéficos. Este estudo teve como objetivos fisiológicos distanciadores de inseticidas de separações científicas para Vespidae Protonectarina sylveirae (Saussure, 1854) e Brachygastra lecheguana. (Latterille, 1824) e espessura de cutícula para avaliação da tolerância entre os 2 anos estes mesmos inseticidas. Como imersas foram folhas de milho (10 x 10 cm) em solução inseticida em dose (100%), subdose (50%) e água destilada (controle) por 5 segundos. Nós podemos ler as folhas e depois embalamos em placas de Petri.Como 20 vespas, por placa, receberam 10% de mel e as placas foram fechadas com tecido de organza fino e elastificadas. Após 24 horas, avaliamos uma porcentagem de vespas mortas. O inseticida alfa-cipermetrina foi altamente tóxico para P. sylveirae e B. lecheguana em dose (100%) e subdose (50%). Os inseticidas Novaluron, chlorantraniliprole, spinosad e indoxacarb foram pouco tóxicos para P. sylveirae e B. lecheguana. dose (100%) e subdose (50%). A alta toxicidade dos inseticidas metomil + novalurom, clorantraniliprole + lambda-cialotrina e deltametrina a P. sylveirae corresponde à menor espessura da cutícula.Portanto, os inseticidas novalurom, clorantraniliprole, spinosad e indoxacarb da selectividade fisiológica para P. sylveirae e B. lecheguana .

The antennal sensilla are sensory organs formed by a group of neurons and accessory cells, which allow perception of environmental cues, which play a role as mechanoreceptors and chemoreceptors. This study describes the post-embryonic development of the antennal sensilla of the stingless Tetragonisca angustula (Hymenoptera: Meliponini) workers. The development of the antennal sensilla begins in the transition stage of the pre-pupae to white-eyed pupae. The sensilla are completely developed at the black-eyed pupae stage, but they are covered by the old cuticle. The sensilla are exposed to the environment only in newly emerged workers of T. angustula, but it is possible that environmental stimuli can be recognized due to the pores in the old cuticle.Keywords: placoid sensilla, trichodea sensilla, stingless bee, pupal development.Desenvolvimento das sensilas antenais de Tetragonisca angustula latreille, 1811 (Hymenoptera: Meliponini) durante a pupação ResumoAs sensilas antenais são órgãos sensoriais formados por um conjunto de neurônios que captam estímulos ambientais e células acessórias, desempenhando as funções de mecanorreceptores e quimiorrecepterores. Este trabalho descreve o desenvolvimento pós-embrionário das sensilas antenais de operárias das abelhas sem ferrão Tetragonisca angustula (Hymenoptera: Meliponini). O desenvolvimento das sensilas tem início na transição de pré-pupa para pupa de olho branco e estão completamente desenvolvidas no estágio de pupa de olho preto, mas ainda estão cobertas pela cutícula velha. As sensilas estão completamente expostas em operárias recém-emergidas de T. angustula, mas é possível que estímulos ambientais sejam percebidos em estágios anteriores devido aos poros presentes na cutícula velha.Palavras-chave: sensila placoide, sensila tricoide, abelha sem ferrão, desenvolvimento pupal.

In queenright colonies of stingless bees of the genus Melipona, workers recognize, attack, and kill young virgin queens. For Melipona scutellaris, we observed that virgin queens were executed when they were between 5 and 9 days old, while newly emerged queens were not attacked. The faster movements of old virgin in relation to newly emerged might be responsible for attacks. It has been also hypothesized that cuticular hydrocarbons are the source of the signal used by workers to recognize virgin queens. We investigated whether newly emerged, 8 days old virgin and physogastric queens of M. scutellaris have different cuticular hydrocarbon profiles. Cuticular hydrocarbons of three ages were compared using gas chromatography-mass spectrometry. The cuticular hydrocarbon profiles varied by reproductive status and age. Changes in the cuticular hydrocarbons in virgin queens during aging suggest that these compounds, together with change in movement, may play a role in the recognition of virgin queens by workers prior to regicide.

Triatoma lecticularia (Hemiptera: Reduviidae) (Stal, 1859) is a potential vector of Chagas's disease and the comprehension of its reproductive biology is an important tool to control this insect. In the reproductive tract of female insects, the spermatheca plays a crucial role storing male spermatozoa after mating. Whithin insects the spermatheca shows a wide morphological diversity and the analysis of this characteristic can contribute to understand the reproductive biology of the species. This study describes the histology and histochemistry of the spermatheca of T. lecticularia. Females have a pair of elongated spermathecal reservoirs without associated accessory gland. The reservoir opens into the common oviduct via a narrow muscular duct. The reservoir epithelium has single layer of columnar secretory cells. The control of the release of spermatozoa from the spermatheca occurs via the muscular duct. The anatomical features of the spermatheca of T. lecticularia resemble those described of other Reduviidae. However, the histological and histochemical features of spermatheca observed in T. lecticularia were important to explain the maintenance of the viability of the spermatozoa stored.Keywords: Triatominae, morphology, secretion, spermatozoa. Morfologia da espermateca de Triatoma lecticularia (Hemiptera: Reduviidae) (Stal, 1859) ResumoTriatoma lecticularia (Hemiptera: Reduviidae) (Stal, 1859) é um potencial vetor da doença de Chagas e a compreensão de sua biologia reprodutiva é um importante fator para seu controle populacional. No aparelho reprodutor feminino dos insetos, a espermateca desempenha a importante funcão de armazenar os espermatozoides após cópula. Nos insetos, a espermateca apresenta uma ampla diversidade morfológica e a análise destas características pode contribuir com o entendimento da biologia reprodutiva das espécies. Este estudo descreve histológica e histoquimicamente a espermateca de T. lecticularia. As fêmeas tem um par de espermatecas alongadas sem glândulas acessórias associadas. O reservatório conecta-se ao oviduto comum através de um ducto muscular curto que controla a liberação dos espermatozoides. O epitélio do reservatório possui uma camada de células secretoras colunares. As características anatômicas da espermateca de T. lecticularia são semelhantes às encontradas em outros Reduviidae. Entretanto, as características histológicas e histoquímicas observadas na espermateca são importantes para explicar a manutenção da viabilidade dos espermatozoides armazenados.