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Item Morphology of the mandibular gland of the ant Paraponera clavata (Hymenoptera: Paraponerinae)(Microscopy Research and Technique, 2019) Andrade, Thito Thomston; Gonçalves, Wagner Gonzaga; Serrão, José Eduardo; Martins, Luiza Carla BarbosaThe ant Paraponera clavata (Fabricius, 1775) is the only extant species of Paraponerinae and is widely distributed in Brazilian forests. Aspects of its biology are documented extensively in the literature; however, knowledge of P. clavata internal morphology, specifically of exocrine glands, is restricted to the venom apparatus. The objective of this study was to describe the mandibular gland morphology of P. clavata workers. The mandibular gland is composed of a reservoir connected to a cluster of Type III secretory cells with cytoplasm rich in mitochondria and lipid droplets, similar to that of other ants. Notably, the glandular secretion is rich in protein and has a solid aspect. This is the first morphological description of the mandibular gland of P. clavata.Item Sperm bundles in the seminal vesicle of the crematogaster victima (Smith) adult males (Hymenoptera: Formicidae)(Neotropical Entomology, 2014-06) Oliveira, C. M.; Lino-Neto, J.; Moreira, J.; Gomes, L. F.; Camargo-Mathias, M. I.This study establishes the presence of spermatodesm in the seminal vesicles of sexually mature males of Crematogaster victima (Smith). In this species, the spermatozoa are maintained together by an extracellular matrix in which the acrosomal regions are embedded. This characteristic has not yet been observed in any other Aculeata. However, the sperm morphology in this species is similar to that described for other ants. The spermatozoa measure on average 100 μm in length, and the number of sperm per bundle is up to 256. They are composed of a head formed by the acrosome and nucleus; this is followed by the flagellum, which is formed by the centriolar adjunct, an axoneme with a 9 + 9 + 2 microtubule pattern, two mitochondrial derivatives, and two accessory bodies. The acrosome is formed by the acrosomal vesicle and perforatorium. The nucleus is filled with compact chromatin with many areas of thick and non-compacted filaments. Both mitochondrial derivatives have the same shape and diameters. The presence of sperm bundles in sexually mature males differentiates C. victima from other ants; however, the similarities in the sperm ultrastructure support the monophyly of this insect group.Item Squamocin induce histological and ultrastructural changes in the midgut cells of Anticarsia gemmatalis (Lepidoptera: Noctuidae)(Ecotoxicology and Environmental Safety, 2018-07-30) Fiaz, Muhammad; Martínez, Luis Carlos; Costa, Marilza da Silva; Cossolin, Jamile Fernanda Silva; Plata-Rueda, Angelica; Gonçalves, Wagner Gonzaga; Sant’Ana, Antônio Euzébio Goulart; Zanuncio, José Cola; Serrão, José EduardoAnnonaceous acetogenins (Annona squamosa Linnaeus) comprises of a series of natural products which are extracted from Annonaceae species, squamocin proved to be highly efficient among those agents. Squamocin is mostly referred as a lethal agent for midgut cells of different insects, with toxic effects when tested against larva of some insects. In present study, LC50 and LC90 of squamocin for A. gemmatalis Hübner (Lepidoptera: Noctuidae) were calculated using probit analysis. Morphological changes in midgut cells were analyzed under light, fluorescence and transmission electron microscopes when larvae were treated with LC50 and LC90 of squamocin for 24, 48 and 72 h. Results revealed that the maximum damage to midgut cells was found under LC90 where it showed digestive cells with enlarged basal labyrinth, highly vacuolated cytoplasm, damaged apical surface, cell protrusions to the gut lumen, autophagy and cell death. The midgut goblet cells showed a strong disorganization of their microvilli. Likewise, in insects treated with squamocin, mitochondria were not marked with Mitotracker fluorescent probe, suggesting some molecular damage in these organelles, which was reinforced by decrease in the respiration rate in these insects. These results demonstrate that squamocin has potential to induce enough morphological changes in midgut through epithelial cell damage in A. gemmatalis.Item Toxicological and morphological effects of tebufenozide on Anticarsia gemmatalis (Lepidoptera: Noctuidae) larvae(Chemosphere, 2018-12) Fiaz, Muhammad; Martínez, Luis Carlos; Plata-Rueda, Angelica; Gonçalves, Wagner Gonzaga; Shareef, Muhammad; Zanuncio, José Cola; Serrão, José EduardoThe velvetbean caterpillar, Anticarsia gemmatalis Hübner (Lepidoptera: Noctuidae), is an important soybean pest in the Americas. Tebufenozide, a novel nonsteroidal ecdysone agonist is used to control this pest. Bioassays were conducted to assess tebufenozide toxicity and their ultrastructural effects on midgut of A. gemmatalis. The toxicity, survivorship, behavior response, and respiration rate for A. gemmatalis larvae after exposure to tebufenozide were evaluated. Also, A. gemmatalis larvae were treated with LC50 obtained from tebufenozide and changes were observed on their midgut cells after 24, 48 and 96 h. Tebufenozide was toxic to A. gemmatalis (LC50 = 3.86 mg mL−1 and LC90 = 12.16 mg mL−1) and survivorship was 95% for adults that had not been exposed to tebufenozide, decreasing to 52% with LC50 and 27% with LC90 estimated value. Damage to midgut cells was increased with exposure time. These cells show damaged striated border with release of protrusions to the midgut lumen, damaged nuclear membrane and nucleus with condensed chromatin and increase in amount of autophagic vacuoles. Mitochondria were modified into nanotunnels which might be an evidence that tebufenozide induces damage to cells, resulting in cell death, proved by immunofluorescence analyses. This insecticide also caused paralysis movement with change in homeostasis and compromised larval respiration. Thus, sublethal exposure to tebufenozide is sufficient to disturb the ultrastructure of A. gemmatalis midgut, which might compromise insect fitness, confirming tebufenozide a possible controlling insecticide.Item Sperm morphology and phylogeny of lagriids (Coleoptera, Tenebrionidae)(Arthropod Structure & Development, 2013-09) Dias, Glenda; Oliveira, Claudia M.; Lino-Neto, JoséThe systematics of tenebrionids remain unclear, principally at the subfamily level, as is the case of the Lagriinae. Considering that sperm morphology has contributed to the various insect group phylogenies, in this work we describe the structure and ultrastructure of these cells in Lagria villosa. Sperm in this species exhibit a strong morphological similarity to those of Tenebrio molitor and Tribolium castaneum, the only two species of Tenebrionidae with previously described sperm. In tenebrionids, the flagellar components offer good diagnostic characters, e.g. the symmetry of mitochondrial derivatives in L. villosa differentiates sperm of this species from those of Te. molitor and Tr. castaneum. However, the lateral association of the nucleus with flagellar components, the form of accessory bodies, and the presence of material connecting the axoneme to the accessory bodies and mitochondrial derivatives indicate that the three species form a sister group. Therefore, the sperm morphology of L. villosa support lagriid beetles as a subfamily (Lagriinae) of Tenebrionidae.Item Phagocytosis of spermatozoa by epithelial cells in the vagina of the lizard Hemidactylus mabouia (Reptilia, Squamata)(Micron, 2011-07) Nogueira, Katiane de Oliveira Pinto Coelho; Araújo, Vinícius Albano; Sartori, Sirlene Souza Rodrigues; Neves, Clóvis AndradeHemidactylus mabouia is an Africa oviparous lizard that is now distributed on other continents and has been introduced to Brazil. In the majority of reptiles, the females have the ability to store spermatozoa in specialized regions of the genital tract. Considering that in H. mabouia the storage of spermatozoa is restricted to the region of the uterine tube, in this study we utilized optical and transmission electron microscopy to investigate the processes related to the large number of spermatozoa in the vagina. Although it was possible to visualize spermatozoa in the vagina, an ultrastructural analysis of the region revealed that significant phagocytosis occurs, which is mediated by the epithelial cells. Such a process indicates that the anterior portion of the vagina is related to the elimination of supernumerary or deficient spermatozoa and not storage.Item Morphology of the male reproductive system and spermatozoa in Centris Fabricius, 1804 (Hymenoptera: Apidae, Centridini)(Micron, 2012-06) Gomes, Luiz Fernando; Badke, Juliana P.; Zama, Uyrá; Dolder, Heidi; Lino-Neto, JoséThe genera Centris and Epicharis constitute the Centridini and are widely distributed in the Neotropical region. Centris is also found in the southern portion of the Neartic region, although both genera are more abundant in the humid tropical regions. To describe the structure of the male reproductive system and spermatozoa, light and transmission electron microscopy were used. The male reproductive system of Centris sp. is formed by a pair of testes, a pair of deferent ducts, a pair of seminal vesicles, a pair of accessory glands and an ejaculatory duct connected to the external genitalia, the aedeagus. In this species, testes and the pre-vesicular deferens ducts as well as the seminal vesicles are encapsulated in a single conjunctive capsule, the scrotal membrane. Each testis consists of four testicular follicles, made up of cysts with up to 64 germinative cells. Histologically, the seminal vesicles are formed by a simple cylindrical epithelium, basal membrane and muscular tunic. The spermatozoa of Centris analis, C. fuscata, C. tarsata and Centris sp. are morphologically similar. They have two easily distinguishable regions: the head and flagellum. The head is formed by the two-layer acrosome, the linear nucleus and the flagellum, the centriole adjunct, the axoneme of pattern 9 + 9 + 2 microtubules, two asymmetric mitochondrial derivatives and two accessory bodies. These Centris species share various morphological characteristics of the male reproductive system and spermatozoa with the other bees previously described, indicating that several characteristics are synapomorphic for the family Apidae. Studies on the morphology of the male reproductive system and spermatozoa in Hymenoptera have demonstrated the diversity of the information provided by these reproductive structures, which can be used in taxonomy studies and the phylogeny of this important group of insects.Item Sperm morphology of Muscidifurax uniraptor (Hymenoptera: Chalcidoidea: Pteromalidae)(Arthropod Structure & Development, 2016-05) Santos, Helen Pinto; Barcellos, Marcelo Silva; Reis, Aline Beatriz; Dolder, Heidi; Lino-Neto, JoséSperm morphology of the parasitoid Muscidifurax uniraptor was investigated under light and transmission electron microscopy. M. uniraptor sperm are filiform, spiraled, approximately 150 μm in length, with a distinctive head, hooded by an extracellular sheath and a flagellum. This extracellular layer, from which many filaments radiate, measures approximately 90 nm in thickness and covers a small acrosome and the anterior nuclear region. The acrosome is composed of an acrosomal vesicle and a perforatorium with its base inserted in the nuclear tip. The nucleus is filled with homogeneously compacted chromatin. The centriolar adjunct extends towards the anterior portion in a spiral around the nucleus for 3.5 μm in length. The two mitochondrial derivatives begin exactly at the centriole adjunct base and, in cross-section, have a circular shape with equal areas that are smaller than the axoneme diameter. It is coiled, with 9 + 9 + 2 microtubules and begins from the centriole, just below the nuclear base. The axoneme is connected to the mitochondrial derivatives by two small irregularly shaped masses. Between the derivatives and the axoneme, the ‘center-flagellar material’ is observed. Overall, these characteristics are recognized in other Chalcidoidea, especially in the eurytomids, but together they form a set of species-specific data.Item Digestive cells in the midgut of Triatoma vitticeps (Stal, 1859) in different starvation periods(Comptes Rendus Biologies, 2010-05-05) Rocha, Lamara Laguardia Valente; Neves, Clóvis Andrade; Zanuncio, José Cola; Serrão, José ÉduardoTriatoma vitticeps (Stal, 1859) is a hematophagous Hemiptera that, although being considered wild, can be found in households, being a potential Chagas’ disease vector. This work describes the histology and ultrastructure of the midgut of T. vitticeps under different starvation periods. Fifteen adults of both sexes starved for 3, 7, 20 and 25 days were studied. In general, digestive cells had apical microvilli, basal plasma membrane infoldings and central nucleus. The perimicrovillar membrane was found in all insects examined. Digestive cells of anterior midgut had lipid droplets, glycogen granules, developed basal labyrinth associated with mitochondria suggesting their role in nutrient storage and in fluid and ion transport. The cells of median and posterior regions of the midgut were rich in rough endoplasmic reticulum, lysosomes, vesicles and granules with different electron-densities. Moreover, cells of the posterior portion of the midgut had hemozoyn granules and mitochondria in the apical cytoplasm close to microvilli, suggesting their role in blood digestion and active nutrient absorption. The midgut of T. vitticeps showed differences in digestive cells associated with the time after feeding, and the increase of vesicles amount in long starvation periods, which suggests enzyme storage, which is readily used after a blood meal.Item Sperm morphology of Trichospilus diatraeae and Palmistichus elaeisis (Hymenoptera: Chalcidoidea: Eulophidae)(Micron, 2013-06-15) Santos, Helen Pinto; Zama, Uyra; Dolder, Heide; Lino-Neto, JoséIn this study, the sperm morphology of the parasitoids Trichospilus diatraeae and Palmistichus elaeisis (Eulophidae) was investigated using light and transmission electron microscopy. In the two species, the sperm are spiral along their entire length and measure about 130 μm and 195 μm in length, respectively. The head region consists of the acrosome and nucleus. The acrosome is composed of an acrosomal vesicle and, in P. elaeisis, a perforatorium. In both species, an extracellular layer in which several filaments are radiated covers the acrosome and the anterior nuclear region. The nuclei are filled with homogeneous and compact chromatin and measure about 50 μm in length in P. elaeisis and 20 μm in T. diatraeae. The flagellum consists of an axoneme with the 9 + 9 + 2 microtubule arrangement spiraled in a long helix, two mitochondrial derivatives coiling around the axoneme and, in P. elaeisis, two accessory bodies. In T. diatraeae were observed transverse striations throughout the central region of the axoneme, whereas the central pair of microtubules was rarely observed. In the final flagellar region in T. diatraeae, different from P. elaeisis, one mitochondrial derivative ends well before the other and both end before the axoneme. The sperm of these two species exhibit features that discriminate one species from each other, as well as characteristics suggest that Eulophidae is closely related to Trichogrammatidae and both of these families are more similar to Eurytomidae than Agaonidae.