ABSTRACT The Afrotropical Zaprionus Coquillett, 1902 (Diptera: Drosophilidae) has gained visibility since the 1990s due to the geographic expansion of Zaprionus indianus Gupta, 1970. More recently, a second species, Zaprionus tuberculatus Malloch, 1932, invaded regions outside its original African regions, causing economic concerns, particularly in Europe. In 2021, Z. tuberculatus was captured for the first time in the Americas, specifically in urban parks, and preserved fragments of the Brazilian Cerrado, causing concerns about the competition with native drosophilids. Here we report the occurrence of Z. tuberculatus 900 km from its first record in urban and rural areas of Viçosa, MG, but not in forest fragments. Considering the great capacity for dispersion and the potential of Z. tuberculatus to compete with native drosophilids species, as well as the potential harm to fruit production when co-occurring with Drosophila suzukii (Matsumura, 1931), further studies would be necessary to monitor this invasion and create mechanisms to control it.

Insetos Asopinae são predadores generalistas e Podisus nigrispinus (Dallas) (Heteroptera: Pentatomidae) é a espécie mais estudada desse grupo no Brasil. O objetivo foi avaliar o desenvolvimento ovariano, a produção de ovos e a oviposição de fêmeas de P. nigrispinus virgens ou acasaladas. Cinco fêmeas com 24 horas de idade foram dissecadas e os ovários foram analisados. Quinze fêmeas desse predador foram acasaladas (T1) e outras 15 foram individualizadas sem acasalamento (T2). Os ovários de cinco fêmeas por tratamento foram dissecados e os ovos maduros e em formação foram contados. Cinco fêmeas virgens de P. nigrispinus com 20 dias de idade foram também analisadas. Fêmeas de P. nigrispinus com 24 horas de idade apresentaram baixo desenvolvimento ovariano, sem evidencia de produção de ovócitos. As fêmeas do tratamento T1 apresentaram ovários completamente desenvolvidos, com 22,67 ± 7,26 ovos maduros e 31,33 ± 1,33 ovos em processo de maturação. Ovários de fêmeas do tratamento T2 apresentaram uma quantidade baixa de ovos nos primeiros estágios de maturação (15 ± 1,73). Fêmeas do tratamento T2, dissecadas aos 20 dias, apresentaram 28,33 ± 2,31 e 15 ± 1,96 ovos maduros e imaturos, respectivamente. Fêmeas de P. nigrispinus iniciam a ovogênese e a maturação dos ovos logo após a emergência, porém o acasalamento é importante para manter a produção dos ovos e a oviposição.

The Asopinae insects are generalist predators, and Podisus nigrispinus (Dallas) (Heteroptera: Pentatomidae) is the most studied species of this group in Brazil. The objective was to study ovarian development, egg production and oviposition of mated and virgin P. nigrispinus females. Five 24-hours-old females were dissected and the ovaries were analyzed. Fifteen females of this predator were mated (T1), and another fifteen were individualized without mating (T2). The ovaries of five females per treatment were dissected and mature and immature eggs were counted. Five virgin females of P. nigrispinus at twenty days old were also analyzed. Twenty-four-hours-old P. nigrispinus females had low ovary development without the evidence of oocyte production. The females of the T1 had completely developed ovaries, with 22.67 ± 7.26 mature eggs and 31.33 ± 1.33 oocytes in the maturation process. Ovaries of females of T2 had a lower quantity of eggs in the early maturation stage (15 ± 1.73). Females of T2 that were dissected at day 20 had 28.33 ± 2.31 and 15 ± 1.96 mature and immature eggs, respectively. Podisus nigrispinus females begin oogenesis and egg maturation soon after their emergence but mating is important to maintain egg production and oviposition.

Bees can form all levels of social organization, from solitary to advanced eusocial societies. Although 80% of the species exist as solitary species, most researches emphasize social species. This study focuses on the description of the male reproductive system of the solitary beesThygater analis (Lepeletier) and Melitoma segmentaria (Fabricius) and searches for traits that support behavioral and phylogenetic studies. The reproductive system of males were dissected, fixed in 2.5% glutaraldehyde in 0.1 M sodium cacodylate buffer pH 7.2 and post-fixed with 1% osmium tetroxide. The tissue was dissected and included for light microscopy. The species presented similar anatomical traits, including paired testicles, seminal vesicles, deferent ducts, accessory glands and an ejaculatory duct. Each testicle was composed of four follicles. In both species, a testicle and a seminal vesicle were surrounded by a joint capsule, forming a seminal vesicle-testicle complex. The two species presented accessory glands with very distinct morphological traits. The anatomic pattern and the histological traits of the reproductive system of the species studied were similar to those described for other bees. In addition, these traits can be used to differentiate species and allow inferences concerning their reproductive biology.

Variações no sistema reprodutor entre os diferentes grupos de Hymenoptera oferecem caracteres que auxiliam nos estudos de comportamento e filogenia. O objetivo deste trabalho foi descrever o sistema reprodutor masculino de três espécies de Trypoxylon (Trypargilum). Para isso, os tecidos foram dissecados, fixados em glutaraldeído 2,5% em tampão cacodilato de sódio 0,1 M, pH 7,2 e pós-fixados em tetróxido de ósmio a 1%. O material foi desidratado e incluído para microscopias de luz e eletrônica de transmissão. As espécies possuem os sistemas reprodutores muito semelhantes, formados por um par de testículos, cada um com três folículos fusiformes, a partir dos quais emerge um ducto eferente que depois se juntam formando o ducto deferente. O ducto deferente termina no ducto ejaculatório. A primeira metade dos ductos deferentes é dilatada e diferenciada em uma região especializada no armazenamento de espermatozóides, a vesícula seminal. A glândula acessória desemboca na região pós-vesicular do ducto deferente. Testículos e vesículas seminais são envoltos por uma única cápsula conjuntiva. Indivíduos maduros sexualmente apresentam todos os estágios da espermatogênese em seus folículos. Os espermatozóides são liberados dos testículos em feixes, os quais estão desorganizados na vesícula seminal.

Variations in the adult male reproductive system among different groups of Hymenoptera offer characteristics that help studies on behavior and phylogenetics. The objective of this study was to describe the adult male reproductive system of three Trypoxylon (Trypargilum) species. For that, tissues were disseced, fixed in 2.5% glutaraldehyde in 0.1 M sodium cacodylate buffer, pH 7.2 and postfixed in 1% osmium tetroxide. The material was dehydratated and embedded for light and electron transmission microscopes. The species have similar reproductive systems, which are formed by a pair of testes, each one with three fusiforme follicles, from which emerges an efferent duct that later joins forming a deferent duct. The deferent duct opens into an ejaculatory duct. The first half of the deferent duct is enlarged and differentiated in a region specialized in sperm storage, the seminal vesicle. The accessory gland flows in the post-vesicular region of the deferent duct. The testes and vesicles are both covered with a conjunctive capsule. Sexually mature individuals have all spermatogenesis stages in their follicles. Sperms are released from testes in bundles which are disorganized inside seminal vesicles.

O termo poliginia se refere à coexistência de duas ou mais rainhas férteis na colônia. Coletou-se no campus da Universidade Federal de Viçosa uma colônia de Acromyrmex subterraneus molestans Santschi contendo 14 rainhas, com o objetivo de verificar se todas elas eram ovipositoras e férteis. O volume do jardim de fungo no ninho era de 500 ml com grande número de larvas e pupas. Observações do desenvolvimento dos ovários e espermatecas indicaram que 13 rainhas tinham copulado e seus ovários não mostraram diferenças morfológicas. Isto indicaria que a poliginia não é acidental e pode representar uma estratégia adaptativa para otimizar o desenvolvimento inicial de colônias em A. subterraneus molestans.

Polygyny denotes the coexistence of two or more mated and fertile queens in the colony. A colony of Acromyrmex subterraneus molestans Santschi containing 14 queens was collected on campus of the Universidade Federal de Viçosa, Brazil, aiming to verify if they were all egg-layers and fertile . The volume of the fungus garden in the nest was about 500 ml with a large number of larvae and pupae. Observation of the ovarian development and spermathecae indicates that 13 queens had copulated and ovary did not show morphological differences among them. This could indicate that polygyny is not accidental and may represent an adaptative strategy to optimize the development of the initial colony in A. subterraneus molestans.

Phlebotominae sand fly specimens were prepared for histological and physiological studies. Different fixatives were tested on sectioned and whole bodied adult females in order to obtain good fixation and provide satisfactory penetration of the embedding media. All fixed specimens were infiltrated (up to seven days under 5ºC) and embedded in hydroxyethyl metacrylate. Two-three µm sections were stained, mounted in Canada balsam and observed by light microscopy. Best results were achieved when whole bodied insects were double fixed in Bouin's and Carnoy's fluids (4 h/2 h) and stained in Hematoxilin/Eosin or fixed in calcium formaldehyde and stained in mercury bromophenol blue.

As fases imaturas do parasitóide Muscidifurax uniraptor Kogan & Legner foram caracterizadas morfologicamente. Pupários de mosca-doméstica com 48-72h de idade foram expostos aos parasitóides adultos em laboratório (25±1ºC, 70±10% U.R. e 14h de fotofase) por um período de 18h. Diariamente, amostras dos pupários foram dissecadas para observação dos imaturos. Em microscópio eletrônico de varredura foram efetuadas medidas de cápsula cefálica das larvas e eletromicrografias dos imaturos. Foi possível determinar quatro ínstares larvais para M. uniraptor. As larvas dos diferentes ínstares são semelhantes na forma geral e nos movimentos, diferindo no tamanho e no volume, apresentando perda gradual de transparência de um ínstar para outro. Houve sobreposição de fases durante o desenvolvimento de ovo a adulto do parasitóide.

The immature stages of the parasitoid Muscidifurax uniraptor Kogan & Legner were morphologically characterized. House fly pupae, 48 to 72-hour old, were exposed to adult parasitoids in laboratory conditions (25 ± 1ºC, 70 ± 10% R.H. and 14 h of photophase) for 18-hour period. Daily, samples of these pupae were dissected for observation of the immatures. Measurements of larval cephalic capsules and electromicrographies of the immatures were made with a scanning electron microscope. M. uniraptor presents four instars wich are very similar in shape and motion, but different in size and volume, and presents a gradual loss of transparency. During the egg to adult development, different stages or larval instars occurred simultaneously.